CN112194818A - Copper/silver-based electrode with conductive bacterial cellulose composite membrane as substrate - Google Patents

Copper/silver-based electrode with conductive bacterial cellulose composite membrane as substrate Download PDF

Info

Publication number
CN112194818A
CN112194818A CN202011032013.9A CN202011032013A CN112194818A CN 112194818 A CN112194818 A CN 112194818A CN 202011032013 A CN202011032013 A CN 202011032013A CN 112194818 A CN112194818 A CN 112194818A
Authority
CN
China
Prior art keywords
cnt
electrode
copper
composite membrane
membrane
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202011032013.9A
Other languages
Chinese (zh)
Other versions
CN112194818B (en
Inventor
洪枫
高璐
陈琳
聂子琪
李宣江
乔锦丽
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Donghua University
National Dong Hwa University
Original Assignee
Donghua University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Donghua University filed Critical Donghua University
Priority to CN202011032013.9A priority Critical patent/CN112194818B/en
Publication of CN112194818A publication Critical patent/CN112194818A/en
Application granted granted Critical
Publication of CN112194818B publication Critical patent/CN112194818B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/36—After-treatment
    • C08J9/40—Impregnation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
    • B01J21/18—Carbon
    • B01J21/185—Carbon nanotubes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
    • B01J23/48—Silver or gold
    • B01J23/50—Silver
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/72—Copper
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
    • B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
    • B01J31/06—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides containing polymers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/20—Catalysts, in general, characterised by their form or physical properties characterised by their non-solid state
    • B01J35/23—Catalysts, in general, characterised by their form or physical properties characterised by their non-solid state in a colloidal state
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
    • B01J35/33—Electric or magnetic properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
    • B01J35/39—Photocatalytic properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/50—Catalysts, in general, characterised by their form or physical properties characterised by their shape or configuration
    • B01J35/58—Fabrics or filaments
    • B01J35/59—Membranes
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
    • C08J5/18—Manufacture of films or sheets
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/88—Processes of manufacture
    • H01M4/8803—Supports for the deposition of the catalytic active composition
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/88—Processes of manufacture
    • H01M4/8825—Methods for deposition of the catalytic active composition
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/90—Selection of catalytic material
    • H01M4/9041—Metals or alloys
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2301/00—Characterised by the use of cellulose, modified cellulose or cellulose derivatives
    • C08J2301/02—Cellulose; Modified cellulose
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2479/00—Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen with or without oxygen, or carbon only, not provided for in groups C08J2461/00 - C08J2477/00
    • C08J2479/02—Polyamines
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2479/00—Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen with or without oxygen, or carbon only, not provided for in groups C08J2461/00 - C08J2477/00
    • C08J2479/04—Polycondensates having nitrogen-containing heterocyclic rings in the main chain; Polyhydrazides; Polyamide acids or similar polyimide precursors
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K2201/00—Specific properties of additives
    • C08K2201/001—Conductive additives
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K2201/00—Specific properties of additives
    • C08K2201/011—Nanostructured additives
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/02—Elements
    • C08K3/04—Carbon
    • C08K3/041—Carbon nanotubes
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/02—Elements
    • C08K3/04—Carbon
    • C08K3/042—Graphene or derivatives, e.g. graphene oxides
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Polymers & Plastics (AREA)
  • Medicinal Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Nanotechnology (AREA)
  • Catalysts (AREA)
  • Inert Electrodes (AREA)
  • Electrodes For Compound Or Non-Metal Manufacture (AREA)

Abstract

The invention relates to a copper/silver-based electrode with a conductive bacterial cellulose composite membrane as a substrate, which takes the composite membrane as the substrate and obtains the electrode by in-situ chemical reduction, catalytic reduction or hydrothermal synthesis of Cu/Ag ions. Compared with the traditional electrode taking carbon cloth as a substrate, the catalytic electrode prepared by the method has a three-dimensional nanofiber network structure, a high specific surface and high conductivity, and has higher catalytic efficiency and longer electrode life. The preparation method is green and environment-friendly, simple in process and short in preparation time. The electrode has good application prospect in the fields of carbon dioxide electro-catalytic reduction, fuel cells, photocatalysis, biocatalysis and the like, and has important significance for environmental protection, energy recycling and the like.

Description

Copper/silver-based electrode with conductive bacterial cellulose composite membrane as substrate
Technical Field
The invention belongs to the field of electrode materials, and particularly relates to a copper/silver-based electrode with a conductive bacterial cellulose composite membrane as a substrate.
Background
Bacterial nanocellulose (BC) is cellulose produced by microorganisms, has excellent mechanical properties, low density and a perfect 3D network structure, is widely applied to the aspects of textiles, medical use, food, conductive materials and the like as a novel material, and has good mechanical properties and reproducible properties compared with synthetic polymers.
The explosion of the industrial revolution, the demand and utilization of fossil fuels by humans are increasing, resulting in resource shortage on the global scale and greenhouse effect caused by carbon dioxide, thereby causing a series of environmental problems such as rise in sea level, melting of glaciers, and the like. Therefore, how to find a new method which can reduce the emission of carbon dioxide and effectively utilize the carbon dioxide as resources becomes a current research hotspot. The technology for converting carbon dioxide into value-added chemicals and fuels attracts wide attention, and the technology for electrochemically reducing carbon dioxide has the advantages of environmental protection, simple device, stable catalytic efficiency, easiness in industrial production and the like. The method can reduce carbon dioxide into high value-added products such as formic acid, methane, methanol, ethylene and the like. Copper is used as a cheap metal, the reserves are abundant, the metal is nontoxic and environment-friendly, carbon dioxide can be effectively reduced into important fossil fuels such as methane, ethylene and the like, and the metal silver has good catalytic activity.
The prior electrode substrate material for electrochemical catalytic reduction of carbon dioxide is carbon paper, carbon cloth, carbon sheet, carbon felt and other materials with certain conductive performance, and the carbon-based materials do not have a nano network structure, so that a catalyst cannot enter the substrate material to be efficiently compounded with the substrate material; the existing preparation method for the carbon dioxide electrochemical catalytic reduction electrode is a coating method, namely a catalyst is coated on a substrate material, the method cannot enable the catalyst and the substrate material to be tightly compounded, and the catalyst is easy to fall into an electrolyte solution in application, so that the efficiency is reduced.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a copper/silver-based electrode with a conductive bacterial cellulose composite membrane as a substrate, and a copper/silver catalyst is subjected to in-situ reduction synthesis in the interior and on the surface of the conductive bacterial cellulose composite membrane by adopting an in-situ compounding method to obtain the copper/silver-based electrode with the conductive bacterial cellulose composite membrane as the substrate and a nanofiber network structure.
The invention relates to a composite electrode material, which is a bacterial cellulose/conductive material composite film with silver or copper nanoparticles loaded on the surface.
The electrode material is of a porous structure, the bacterial cellulose is used as a natural biological material, the electrode material has a 3D nano-fiber network structure, and the porous conductive composite membrane with the 3D nano-network structure can be obtained after the electrode material is compounded with a low-dimensional carbon material LDC, polypyrrole PPy and polyaniline PANI.
The electrode material is as follows: preparing a conductive composite membrane from the bacterial nano-cellulose, LDC, PPy and PANI by an in-situ culture method, an impregnation method, a homogenate suction filtration method and an in-situ chemical polymerization method; the obtained composite membrane is used as a substrate to carry out in-situ catalytic reduction or hydrothermal synthesis on Cu and/or Ag ions, and the preparation method comprises the following steps: Cu/C @ BC, Ag/C @ BC, Cu/PPy @ BC, Ag/PPy @ BC, Cu/PANI @ BC, Ag/PANI/C @ BC or Cu/PANI/C @ BC electrodes, namely copper/silver-based and other metal catalyst electrodes.
Further, the concentrations of CNT, PPy and PANI were 0.1M.
The size of the Cu/C @ BC, Ag/C @ BC, Cu/PPy @ BC, Ag/PPy @ BC, Cu/PANI @ BC, Ag/PANI/C @ BC or Cu/PANI/C @ BC electrode is 1 multiplied by 1 to 3cm2。
The conductive material is one or more of a low-dimensional carbon material LDC, polypyrrole PPy and polyaniline PANI; the bacterial nano cellulose comprises various different forms such as a bacterial nano cellulose film, a bacterial nano cellulose homogenate, a bacterial nano cellulose flocculent fiber, a spongy bacterial nano cellulose obtained by freeze drying and the like.
The low-dimensional carbon material LDC comprises zero-dimensional, one-dimensional and two-dimensional materials, and specifically comprises the following components: one or more of carbon nano tube CNT, graphene and nano carbon powder.
Further, the carbon nanotubes include various carbon nanotubes such as single-walled carbon nanotubes, multi-walled carbon nanotubes, and carboxylated multi-walled carbon nanotubes, and the graphene includes various graphenes such as single-layer graphene, double-layer graphene, few-layer graphene, and multi-layer graphene.
The preparation method of the composite electrode material comprises the following steps:
(1) immersing the bacterial cellulose/conductive material composite membrane into a copper-containing or silver ion water solution, and carrying out oscillation impregnation in a constant-temperature water bath oscillator at the temperature of 30-90 ℃;
(2) and (2) under the ice-water bath condition, uniformly mixing sodium hydroxide, a stabilizer and a reducing agent to obtain a mixed solution, then adding the mixed solution into the copper or silver ion aqueous solution containing the composite membrane in the step (1), then placing the mixed solution into a water bath constant temperature oscillator to oscillate at the temperature of 30-90 ℃, and drying to obtain the electrochemical catalytic electrode.
The preferred mode of the above preparation method is as follows:
the bacterial cellulose/conductive material composite membrane in the step (1) is as follows: by taking bacterial nano-cellulose as a substrate, one or more conductive materials of low-dimensional carbon material (LDC), polypyrrole (PPy) and Polyaniline (PANI) are compounded. Such as forming C @ BC, PPy @ BC, PANI @ BC, PPy/C @ BC, PANI/C @ BC conductive composite films.
The bacterial cellulose/conductive material composite membrane in the step (1) is of a 3D nano network structure; the copper ion-containing aqueous solution is a copper sulfate aqueous solution, a copper chloride aqueous solution or a copper nitrate solution; the silver ion-containing aqueous solution is silver nitrate aqueous solution; the concentration of the copper or silver ion-containing aqueous solution is 0.1-0.4M.
The shaking and dipping time in the step (1) is 8-48 h.
The stabilizer in the step (2) is one or more of L-ascorbic acid, ethanol and citric acid; the reducing agent is one or two of sodium borohydride and potassium borohydride; the concentration of the reducing agent in the mixed solution is 0.2-0.4M, the concentration of the sodium hydroxide is 1M, and the concentration of the stabilizing agent is 0.2-0.8M.
The oscillation time in the step (2) is 30-90 min; the drying is carried out in a vacuum drying oven at 50-90 deg.C for 30-90 min.
The molar concentration ratio of the copper or silver ions to the reducing agent is 4: 2-4: 4; the molar concentration ratio of the copper/silver ions to the stabilizer is 2: 1-2: 4.
The rotating speed of the water bath oscillator in the steps (1) and (2) is 70-80 r/min.
The zero-valent elemental metal copper/silver has a nanoscale. (i.e., the copper/silver catalyst is reduced to the zero-valent copper/silver catalyst with nanometer size in situ in the bacterial cellulose/conductive material composite membrane)
The C @ BC, PPy @ BC and PANI @ BC composite membrane obtained by the method is of a 3D nano-mesh structure, and the porous junction is obtained by effectively adjusting the proportion of reactants, the impregnation time, the reaction temperature and the like of the composite membraneThe conductive composite film of the structure loads the nano copper/silver electrode, reduces the occurrence of hydrogen evolution reaction, reduces higher overpotential in the reaction process, and improves CO2Utilization and conversion.
The invention provides an application of the composite electrode material in carbon dioxide electrocatalysis, fuel cells, photocatalysis or biocatalysis.
Furthermore, the Cu/C @ BC, Ag/C @ BC, Cu/PPy @ BC, Ag/PPy @ BC, Cu/PANI @ BC, Ag/PANI/C @ BC or Cu/PANI/C @ BC electrode prepared by the method is used for carbon dioxide electrochemical reduction, the production process is green and environment-friendly, and the electrode can be produced in large quantity, the 3D nano-network structure and the hydrophilicity thereof can well load the copper/silver nano-particles with C @ BC, PPy @ BC, PANI/C @ BC, and the PANI/C @ BC composite membrane to synthesize the Cu/C @ BC, Ag/C @ BC, Cu/PPy @ BC, Cu/PANI @ BC, Ag/PANI/C @ BC or Cu/PANI/C @ nanometer electrode, and can greatly improve the electrochemical specific surface area, more catalytic active sites are provided, thereby improving the Faraday efficiency of the product.
The electrode is prepared by a simple chemical in-situ reduction, ultraviolet irradiation reduction, catalytic reduction or hydrothermal synthesis method, the C @ BC, PPy @ BC, PANI @ BC, PPy/C @ BC, PANI/C @ BC composite membrane is soaked in a copper/silver ion-containing solution, and a Cu/C @ BC, Ag/C @ BC, Cu/PPy @ BC, Ag/PPy @ BC, Cu/PANI @ BC, Ag/PANI/C @ BC or Cu/PANI/C @ BC electrode with a large specific surface area and loaded with nano copper/silver is obtained by changing the soaking time, so that the contact specific surface area of carbon dioxide and a catalyst is increased, more catalytic active sites are provided, and the hydrogen evolution process in the reaction process can be effectively inhibited; and simultaneously, the Cu/C @ BC, Ag/C @ BC, Cu/PPy @ BC, Ag/PPy @ BC, Cu/PANI @ BC, Ag/PANI/C @ BC or Cu/PANI/C @ BC electrode with the nano structure is obtained by effectively regulating and controlling the preparation conditions (time, temperature, reducing agent ratio and stabilizing agent ratio) of the catalyst electrode copper/silver-based electrode.
Advantageous effects
(1) Compared with the traditional electrode taking carbon cloth as a substrate, the catalytic electrode prepared by the method has a three-dimensional nanofiber network structure and a high specific surface, so that the catalytic efficiency is higher, and the service life of the electrode is longer.
(2) The patent proposes that copper/silver nanoparticles are loaded on a bacterial cellulose composite membrane with electroconductivity in situ to carry out CO2Electrochemical reduction is carried out, and more CO is obtained by effectively regulating and controlling the preparation conditions of the electrode2The active sites are catalyzed and reduced, thereby improving the catalytic activity of the catalyst and the selectivity of catalytic products and improving the Faraday efficiency of the products.
(3) The conductive composite membrane related by the invention is a 3D nano-mesh structure, and the porous composite membrane loaded nano-copper/silver electrode with the porous structure such as C @ BC, PPy @ BC, PANI @ BC and the like is obtained by effectively adjusting the proportion among reactants, the dipping time, the reaction temperature and the like of the composite membrane, so that the occurrence of hydrogen evolution reaction is reduced, higher overpotential in the reaction process is reduced, and CO is improved2The utilization rate and conversion rate of the Cu/CNT @ BC can be seen from FIG. 17, wherein the CO of the Cu/CNT @ BC is obtained by using the CNT @ BC as a substrate material2The hydrogen evolution reaction decreases with increasing potential in the Faraday efficiency diagram of the electrochemical reduction product, and CO2The utilization rate and the conversion rate are increased.
(2) The preparation method is green and environment-friendly, has simple process, short preparation time, low energy consumption, easy operation and easy large-scale production.
(3) The catalytic electrode of the invention effectively improves CO2Ethylene selectivity during reduction.
(4) The electrode has good application prospect in the fields of carbon dioxide electro-catalytic reduction, fuel cells, photocatalysis, biocatalysis and the like, and has important significance in environmental protection, energy recycling and the like.
Drawings
FIG. 1 is a LSV curve comparing a Cu/CNT @ BC electrode with a pure carbon cloth, a Cu @ carbon cloth, a pure BC, a CNT @ BC, a Cu @ BC of example 1;
FIG. 2 is a macroscopic view of CNT @ BC composite membranes in example 1 cultured in situ statically at different concentrations;
FIG. 3 is a macroscopic view of a dynamic in situ cultured CNT @ BC composite membrane according to example 2; wherein A1 is a visual diagram; a2 is an expanded view;
FIG. 4 is a microscopic SEM image of different concentrations of CNT @ BC composite membrane statically cultured in situ in example 1;
FIG. 5 is a microscopic SEM image of the dynamically in situ cultured CNT @ BC composite membrane of example 2; wherein the magnification of B1, B2 and B3 is 10K, 5K or 2K;
FIG. 6 shows flexibility of the PPy/CNT @ BC composite film of example 12; wherein A is the flexibility of the PPy/CNT @ BC composite film, and B is the flexibility of the PPy @ BC composite film;
FIG. 7 is a microscopic SEM image of a PPy @ BC composite membrane obtained by in-situ polymerization in example 5; wherein the magnification of B1 and B2 is 10K and 2K;
FIG. 8 is a graph of the conductivity versus water content for different concentrations of CNT @ BC composite films of example 1;
FIG. 9 shows the reduction of CO by reducing agent with different ratios of Cu/CNT/@ BC electrode in example 12Graph of CV of (a); the numerical ratio in the figure is the molar concentration ratio of the copper ions to the reducing agent; the Cu/CNT/@ BC electrode is prepared only by different molar concentration ratios of copper ions and a reducing agent, and the other conditions are the same;
FIG. 10 shows the catalytic reduction of CO by Cu/CNT/@ BC electrode in example 1 at different soaking times2The LSV graph of (a); the preparation process of the Cu/CNT/@ BC electrode is different only in the soaking time, and the other conditions are the same;
FIG. 11 is the catalytic reduction of CO by Cu/CNT/@ BC electrode in example 1 under different reaction times2The electrical conductivity of (a); wherein the preparation process of the Cu/CNT/@ BC electrode is only different in reaction time, and the rest conditions are the same;
FIG. 12 is the catalytic reduction of CO by Cu/CNT/@ BC electrode in example 1 at different reaction temperatures2The LSV graph of (a); the preparation process of the Cu/CNT/@ BC electrode is different only in that the reaction temperature is different, and the rest conditions are the same;
FIG. 13 shows the ratio of ascorbic acid to carbon monoxide for the catalytic reduction of CO by Cu/CNT/@ BC electrode in example 12Graph of CV of (a); wherein the numerical ratio in the figure is the molar concentration ratio of the copper ions to the stabilizer; wherein the Cu/CNT/@ BC electrode is prepared by a process which is different only in the molar ratio of the copper ions to the stabilizerThe concentration ratio is different, and the other conditions are the same;
FIG. 14 is a microscopic SEM photograph of whether the Cu/CNT/@ BC electrode is added with ascorbic acid or not in example 3;
FIG. 15 shows Cu/CNT/@ BC in example 10NaBH4It diagram of electrodes under different voltages;
FIG. 16 shows Cu/CNT/@ BC in example 4KBH4The unit of the electrode in a long time and the Faraday efficiency are combined;
FIG. 17 shows Cu/CNT/@ BC in example 10NaBH4Faraday efficiency plots of the electrodes at different voltages;
FIG. 18 shows Cu/CNT @ BC in examples 4 and 10KBH4And Cu/CNT @ BCNaBH4The double layer capacitance fit plot of (1);
FIG. 19 is a graph of a double layer capacitance fit of the Cu @ carbon cloth, Cu @ BC and Cu/CNT @ BC composite electrode of example 1;
FIG. 20 is a LSV diagram of composite films of Cu/CNT @ BC, Cu/PPy @ BC, Cu/PANI/CNT @ BC, Ag/PPy @ BC, Ag/PANI/CNT @ BC in accordance with various embodiments;
FIG. 21 is a LSV plot of the nickel copper @ carbon cloth (8:2) versus Cu/PPy @ BC electrodes of comparative example 1;
FIG. 22 is a CV diagram of the nickel copper @ carbon cloth (1:9) and Ag/PPy @ BC electrodes of comparative example 2;
FIG. 23 shows Cu/CNT @ BC in examples 4 and 10KBH4And Cu/CNT @ BCNaBH4Microscopic SEM image of (a).
Detailed Description
The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.
Example 1
The copper-based electrode for electrochemical catalysis in the embodiment is composed of a CNT @ BC composite membrane loaded nano-copper electrode which is statically cultured in situ, the electrode is synthesized by an in situ catalytic reduction method, and the preparation method comprises the following steps:
(1) acetobacter xylinum strain (Komagataeibacter xylinus ATCC23770, the same below) was added with carbon nanotubes (industrial multi-walled carbon nanotubes,>90%, inner diameter of 5-15nm, outer diameter:>50nm, length 10-20 μm, 50g, Allantin reagent (Shanghai) Co., Ltd., other examples are the same) and fermentation medium (50g/L glucose, C)6H12O6AR, national drug group reagents ltd; 5g/L tryptone, BR, national pharmaceutical group reagents, Inc.; 3g/L yeast powder, BR, the national drug group reagent company, the same below) mixed solution (in-situ standing and constant temperature culture for 2-3 days, taking out the CNT @ BC composite membrane, placing the CNT @ BC composite membrane in a sodium hydroxide (NaOH, analytical reagent, the national drug group Shanghai chemical reagent company, the same below) solution, treating the CNT @ BC composite membrane for 2-4 hours at 80 ℃, taking out the CNT @ BC composite membrane, and rinsing the CNT @ BC composite membrane to be neutral by using deionized water to obtain the CNT @ BC composite membrane.
(2) The membrane was analyzed by CV (cyclic voltammetry, scan range was set to-1.36-0.43V (vs. RHE), respectively), and scan rate was set to 50mV-1，0.5M K2HCO3And (3) solution. ) LSV (Linear sweep voltammetry, Linear sweep range was set to coincide with the range of cyclic voltammetric sweep at a 5 mV. um-1，0.5M K2HCO3And (3) solution. ) Conductivity (AC impedance method, its scanning frequency is 0.1Hz-100KHz, and its voltage amplitude is 100 mA. Conductivity δ (S/cm) ═ L/RTW L ═ 0.5cm, W ═ 1cm, R ═ impedance, and T ═ film thickness. ) Equal performance characterization, the CNT @ BC composite film with the carbon nanotube concentration of 0.1M was preferably selected for the experiments of the following steps (see fig. 2, 4 and 8).
(3) 0.1M of CuSO was weighed4·5H2Dissolving O (AR, national medicine group reagent Co., Ltd., the same below) in 50mL of deionized water, stirring thoroughly, mixing well, placing in a 1X 2cm container2The CNT @ BC composite membrane is soaked for 24 hours in a water bath constant temperature oscillator under the condition of 30 ℃.
(4) 0.5g NaOH was mixed with 1.76g L-ascorbic acid (C)6H8O6AR, national drug group reagent Co., Ltd., the same below) was dissolved in 12.5mL of deionized water, and the mixture was stirred sufficiently in an ice bath and added0.09g of NaBH4(98 wt%, national drug group reagents Co., Ltd., the same below) were thoroughly mixed, and the mixture was added dropwise to a CNT @ BC composite membrane immersed in a copper sulfate solution by a constant flow pump at 70rpm, and shaken in a 30 ℃ water bath constant temperature shaker for 60min, and then deionized water and ethanol (CH) were used3CH2OH, AR, Hongsheng fine chemical industry Co., Ltd., Hemo city, the same below) washing the membrane, and drying at 60 ℃ for 2h to obtain a Cu/CNT @ BC electrode (the concentration of CNT is 0.1M, and the molar concentration ratio of copper ions to the reducing agent is 4: 2; the dipping time is 24 hours; the reaction time is 60 min; the reaction temperature is 30 ℃; the molar concentration ratio of the copper ions to the stabilizer is 1: 2).
(5) Using acetobacter xylinum as a strain, performing static culture for 2-4 days to prepare a bacterial cellulose pure film, taking out the pure film, placing the pure film into a sodium hydroxide solution, treating the pure film at 80 ℃ for 2-4 hours, taking out the pure film, and rinsing the pure film with deionized water to be neutral to obtain the pure BC film. 0.1M of CuSO was weighed4·5H2Dissolving O in 50mL deionized water, stirring, mixing, adding into 1 × 2cm2And oscillating the mixture for 24 hours at the temperature of 30 ℃ in a water bath constant temperature oscillator. 0.5g NaOH and 1.76g L-ascorbic acid were dissolved in 12.5mL deionized water, ice-bathed, stirred well and added with 0.09g NaBH4Fully mixing, dropwise adding the mixture into BC soaked in a copper sulfate solution through a constant flow pump at 70rpm, oscillating in a water bath constant temperature oscillator at 30 ℃ for 60min, washing the membrane with deionized water and ethanol, and drying at 60 ℃ for 2h to obtain the Cu @ BC electrode.
(6) 0.1M of CuSO was weighed4·5H2Dissolving O in 50mL deionized water, stirring, mixing, adding into 1 × 2cm2Was shaken for 24 hours in a water bath constant temperature shaker at 30 ℃ in a carbon cloth (WOS1009, Taiwan carbon energy Co., Ltd., the same below). 0.5g NaOH and 1.76g L-ascorbic acid were dissolved in 12.5mL deionized water, ice-bathed, stirred well and added with 0.09g NaBH4Fully mixing, dropwise adding the mixture into carbon cloth soaked in a copper sulfate solution through a constant flow pump at 70rpm, oscillating the mixture in a water bath constant temperature oscillator at 30 ℃ for 60min, washing the membrane with deionized water and ethanol, and drying the membrane at 60 ℃ for 2h to obtain the Cu @ carbon cloth electrode.
FIG. 1 is a LSV plot of pure BC, CNT @ BC, pure carbon cloth, Cu @ BC, and Cu/CNT @ BC, showing the conductive properties of the BC after the addition of CNT; the composite electrode is also compounded with Cu, and the current density of the Cu @ BC composite electrode taking BC as a substrate is higher than that of the Cu @ carbon cloth electrode taking carbon cloth as a substrate; the Cu/CNT @ BC composite electrode has the highest current density and excellent electrochemical reduction performance.
Fig. 2 shows the macroscopic morphologies of the CNT @ BC composite film and the pure BC at the concentrations of 0.2M, 0.1M, and 0.05M, respectively, and it can be observed that the CNT and BC are more uniformly composited.
FIG. 4 is a SEM image of a static-state-cultured CNT @ BC composite membrane with the concentrations of 0.2M, 0.1M and 0.05M, respectively, showing that the fibers are wound with agglomerated CNT spheres, and the more CNT spheres are loaded on the surface of the fibers, the more CNT spheres are stacked. It can be obviously observed that more BC fibers are on CNT spheres on the 0.05M CNT @ BC composite film, and the BC fibers on the CNT spheres are obviously reduced along with the increase of the concentration of the CNT, because the addition of the CNT has a certain inhibition effect on the growth of the BC fibers, which indicates that the CNT and BC are cultured in situ, but the CNT with proper concentration is selected to be compounded with the BC fibers, and the composite film grows better when the concentration of the CNT is higher.
As shown in fig. 8, the water contents and conductivities of the CNT @ BC composite film and the pure BC at concentrations of 0.2M, 0.1M and 0.05M respectively are shown in a combined graph, which shows that the water contents of the pure BC and the CNT @ BC composite film are not greatly changed; as the loading concentration of the CNT increases, the conductivity of the CNT @ BC composite film also increases.
As shown in fig. 9, fig. 10, fig. 11, fig. 12, and fig. 13, the process optimization of the Cu/CNT @ BC nanocomposite electrode preparation process includes optimization of the molar concentration ratio of copper ions to the reducing agent (CV diagram), the immersion time (LSV diagram), the reaction temperature (LSV diagram), the reaction time (conductivity bar diagram), and the molar concentration ratio of copper ions to the stabilizer (CV diagram). From the figure, the current density with the molar concentration ratio of copper ions to the reducing agent of 4:3 is the maximum; the current density is maximum when the dipping time is 48h, and the peak potential is maximum; the reaction time is 90min, and the conductivity is maximum; the current densities at the reaction temperature of 60 ℃ and 90 ℃ are basically the same; the current density with the molar concentration ratio of copper ions to the stabilizer being 1:1 is the maximum; note: wherein the dipping time is the oscillation dipping time in the step (3); the reaction temperature is the temperature of the water bath in the step (4); the reaction time is the water bath reaction time in the step (4).
As shown in fig. 19, the results show that the electrochemical activity specific surface area of the Cu/CNT @ BC composite electrode is the largest, and the electrochemical activity specific surface area of the Cu @ carbon cloth electrode is the smallest, which indicates that the BC with the 3D nano-network structure is beneficial to increase the electrochemical activity specific surface area of the catalyst and has higher catalytic efficiency compared with the conventional carbon cloth electrode; meanwhile, the Cu/CNT @ BC composite electrode subjected to in-situ reduction is more compact in composition with a catalyst than a Cu @ carbon cloth electrode substrate material prepared by a coating method, so that the Cu/CNT @ BC composite electrode has longer electrode life.
Example 2
The silver-based electrode for electrochemical catalysis in the embodiment is composed of a CNT @ BC composite membrane loaded nano-copper electrode which is dynamically cultured in situ, the electrode is synthesized by an in situ catalytic reduction method, and the preparation method comprises the following steps:
(1) using acetobacter xylinum as a strain, adding 200mL of mixed solution of a carbon nano tube and a culture medium with the concentration of 0.1M into a horizontal rotary drum reactor, adding two drops of Tween 80 serving as a dispersing agent by using a rubber head dropper, uniformly mixing, and culturing for 24 hours. Continuously adding 200ml of 0.1M CNT and fermentation liquor mixed culture medium into a glass fermentation tank through a peristaltic pump in an aseptic working platform, and carrying out subsequent fermentation for 24 h. And (3) taking out the CNT @ BC composite membrane, placing the CNT @ BC composite membrane in a sodium hydroxide solution, treating the CNT @ BC composite membrane for 2-4h at 80 ℃, taking out the CNT @ BC composite membrane, and rinsing the CNT @ BC composite membrane to be neutral by using deionized water to obtain the CNT @ BC composite membrane.
(3) Weighing 0.1M AgNO3(AR, national medicine group reagent Co., Ltd., the same below) was dissolved in 50mL of deionized water, sufficiently stirred and mixed well, and then placed in a volume of 1X 2cm2The CNT @ BC composite membrane is vibrated for 24 hours at the temperature of 30 ℃ in a water bath constant temperature oscillator.
(4) 0.5g NaOH and 0.88g L-ascorbic acid were dissolved in 12.5mL deionized water, ice-bathed, stirred well and added with 0.14g NaBH4Mixing thoroughly, adding dropwise into AgNO solution by constant flow pump at 70rpm3In the CNT @ BC composite membrane in the solution, oscillating for 60min in a water bath constant temperature oscillator at 30 ℃, and thenWashing the membrane with deionized water and ethanol, and drying at 60 ℃ for 2h to obtain the Ag/CNT @ BC electrode (the molar concentration ratio of silver ions to a reducing agent is 4:3, the impregnation time is 24h, the reaction time is 60min, the reaction temperature is 30 ℃, and the molar concentration ratio of silver ions to a stabilizing agent is 1: 1).
As shown in fig. 3, which shows the macro-morphology of the dynamically cultured CNT @ BC composite film, it can be observed that both the inner and outer surfaces of the composite film exhibit a very smooth and uniform black color.
As shown in fig. 5, which is a SEM image of a dynamically cultured 0.1M CNT @ BC composite membrane, CNTs are woven into a BC network from the SEM image, each coarse fiber is spirally wound with a plurality of microfibers, and the CNTs are wrapped inside to form a rope-like structure and penetrate through each other to construct a CNT @ BC three-dimensional network structure.
Example 3
The copper-based electrode for electrochemical catalysis in the embodiment is composed of a CNT @ BC composite membrane loaded nano-copper electrode which is subjected to immersion culture, the electrode is synthesized by an in-situ catalytic reduction method, and the preparation method comprises the following steps:
(1) using acetobacter xylinum as a strain, performing static culture for 2-4 days to prepare a bacterial cellulose pure film, taking out the pure film, placing the pure film into a sodium hydroxide solution, treating the pure film at 80 ℃ for 2-4 hours, taking out the pure film, and rinsing the pure film with deionized water to be neutral to obtain the pure BC film.
(2) And (3) dynamically dipping the BC pure film by using a carbon nano tube aqueous solution with the concentration of 0.1M, dynamically oscillating in a constant temperature oscillator at 30 ℃ for 24h, and taking out to obtain the CNT @ BC composite film. The multi-wall carbon nano-tube can be dispersed for 30min by an ultrasonic probe of an ultrasonic cleaner or an ultrasonic crusher in advance, and two drops of surfactant can be dripped into aqueous solution to be used as dispersing agent, such as Tween 20, Tween 80, coated easy dispersing agent DS-195, DS-172, DS-194H, cationic surfactant cetyl dimethyl ammonium bromide (CTAB), anionic surfactant Sodium Dodecyl Benzene Sulfonate (SDBS) and nonionic surfactant polyethylene glycol octyl phenyl ether (Triton X-100).
(3) 0.1M of CuSO was weighed4·5H2Dissolving O in 50mL deionized water, stirring, mixing, and adding into 1 × 2cm2And the CNT @ BC composite membrane is put in a water bath constant temperature oscillatorShaking at 30 deg.C for 48 h.
(4) 0.5g NaOH and 0.44g L-ascorbic acid were dissolved in 12.5mL deionized water, ice-bathed, stirred well and added with 0.19g NaBH4The components are fully mixed, and are dripped into a CNT @ BC composite membrane soaked in a copper sulfate solution through a constant flow pump at 70rpm, the mixture is vibrated for 60min in a water bath constant temperature oscillator at 30 ℃, then the membrane is washed by deionized water and ethanol, and the membrane is dried for 2h at 60 ℃ to obtain a Cu/CNT @ BC electrode (the molar concentration ratio of copper ions to a reducing agent is 4:4, the soaking time is 48h, the reaction time is 60min, the reaction temperature is 30 ℃, and the molar concentration ratio of the copper ions to a stabilizing agent is 2: 1).
As shown in fig. 14, the reduced catalyst particles were smaller and more uniform after addition of ascorbic acid.
Example 4
The copper-based electrode for electrochemical catalysis in the embodiment is composed of a porous CNT @ BC composite membrane loaded nano-copper electrode, the electrode is synthesized by an aqueous solution chemical reduction method, and the preparation method comprises the following steps:
(1) using acetobacter xylinum as a strain, performing static culture for 2-4 days to prepare a bacterial cellulose pure film, taking out the pure film, placing the pure film into a sodium hydroxide solution, treating the pure film at 80 ℃ for 2-4 hours, taking out the pure film, and rinsing the pure film with deionized water to be neutral to obtain the pure BC film.
(2) And (3) shearing the prepared BC pure film by using scissors, putting the BC pure film into a high-speed homogenizer to obtain BC homogenate, adding the same amount of CNT powder, uniformly mixing, and performing suction filtration to form the film.
(3) 0.1M of CuSO was weighed4·5H2Dissolving O in 50mL deionized water, stirring, mixing, and adding into 1 × 2cm2The CNT @ BC composite membrane is vibrated for 48 hours at the temperature of 30 ℃ in a water bath constant temperature oscillator.
(4) 0.5g NaOH and 1.76g L-ascorbic acid were dissolved in 12.5mL deionized water, ice-bathed, stirred well and added with 0.13g KBH4(97 wt%, national drug group reagents Co., Ltd., the same below) were mixed thoroughly, and the mixture was added dropwise to a CNT @ BC composite membrane immersed in a copper sulfate solution by a constant flow pump at 70rpm, and oscillated in a water bath constant temperature oscillator at 30 ℃ for 30min, and then deionized water and deionized water were addedWashing the membrane with ethanol, and drying at 60 ℃ for 2h to obtain the Cu/CNT @ BC electrode (4:2-48h-30min-30 ℃). (the molar concentration ratio of the copper ions to the reducing agent is 4: 2; the immersion time is 48 h; the reaction time is 30 min; the reaction temperature is 30 ℃, and the molar concentration ratio of the copper ions to the stabilizing agent is 1: 2).
Shown in FIG. 16 as Cu/CNT/@ BCKBH4The it and Faraday efficiency of the electrode are combined and plotted for a long time, and Cu/CNT @ BC is shownKBH4The tendency of the current density course of the electrode to decrease first and then increase as the electrolysis time increases, and FE of the electrode at the beginning of the electrolysisCOAnd FEC2H4Are all small and have FE's with increasing electrolysis timeCOAnd FEC2H4Gradually increase of CO thereof2The electrochemical reduction performance also gradually increases.
Example 5
The copper-based electrode for electrochemical catalysis in the embodiment is composed of a nano copper electrode loaded with a PPy @ BC composite film obtained by an in-situ polymerization method, the electrode is synthesized by an in-situ catalytic reduction method, and the preparation method comprises the following steps:
(1) using acetobacter xylinum as a strain, performing static culture for 2-4 days to prepare a bacterial cellulose pure film, taking out the pure film, placing the pure film into a sodium hydroxide solution, treating the pure film at 80 ℃ for 2-4 hours, taking out the pure film, and rinsing the pure film with deionized water to be neutral to obtain the pure BC film.
(2) Cutting the purified BC membrane into 1 × 2cm2The membrane was placed on a water-absorbent filter paper, a small amount of free water was removed from the BC membrane, and the BC membrane was put into a 150ml notched bottle containing 0.1M pyrrole monomer (chemical purity, national drug group chemical reagents Co., Ltd., the same below) and reacted for 2 hours under magnetic stirring, so that the BC membrane sufficiently adsorbed the pyrrole monomer. Subsequently 15ml FeCl containing 0.1M concentration were added dropwise3(CP, not less than 97.0%, national drug group chemical reagent Co., Ltd., the same below) solution, reacting for 2h under ice water bath condition, polymerizing pyrrole on the surface of BC membrane, and uniformly coating on BC fiber. And (3) cleaning the membrane by using 75% (v/v) ethanol and distilled water to obtain the PPy @ BC composite membrane.
(3) 0.1M of CuSO was weighed4·5H2Dissolving O in 50mL deionized water, stirring, mixing, and adding into 1 × 2cm2The PPy @ BC composite membrane is combinedOscillating for 24h in a water bath constant temperature oscillator at 30 ℃.
(4) 0.5g NaOH and 1.76g L-ascorbic acid were dissolved in 12.5mL deionized water, ice-bathed, stirred well and added with 0.20g KBH4The materials are fully mixed, the mixture is dripped into a PPy @ BC composite membrane soaked in a copper sulfate solution through a constant flow pump at 70rpm, the mixture is vibrated for 60min in a water bath constant temperature oscillator at 30 ℃, then the membrane is washed by deionized water and ethanol, and the membrane is dried for 2h at 60 ℃ to obtain a Cu/PPy @ BC electrode (the molar concentration ratio of copper ions to a reducing agent is 4:3, the soaking time is 24h, the reaction time is 60min, the reaction temperature is 30 ℃, and the molar concentration ratio of silver ions to a stabilizing agent is 1: 2).
Fig. 7 shows a microscopic SEM image of the PPy @ BC composite membrane obtained by in-situ polymerization, which shows that after adding PPy, the three-dimensional network structure of BC is better preserved, and the diameter of the fiber of PPy @ BC composite membrane is increased.
Example 6
The silver-based electrode for electrochemical catalysis in the embodiment is composed of a nano copper electrode loaded on a PANI @ BC composite membrane obtained by an in-situ polymerization method, the electrode is synthesized by an in-situ catalytic reduction method, and the preparation method comprises the following steps:
(1) using acetobacter xylinum as a strain, performing static culture for 2-4 days to prepare a bacterial cellulose pure film, taking out the pure film, placing the pure film into a sodium hydroxide solution, treating the pure film at 80 ℃ for 2-4 hours, taking out the pure film, and rinsing the pure film with deionized water to be neutral to obtain the pure BC film.
(2) Cutting the purified BC membrane into 1 × 2cm2Placing on a water absorption filter paper, removing a small amount of free water of a BC membrane, putting the BC membrane into a 150ml cut bottle containing aniline monomer (AR ≥ 99.5%, national drug group chemical reagent, Inc., the same below) with the concentration of 0.1M, and reacting for 2h under the action of magnetic stirring to enable the BC membrane to fully adsorb the aniline monomer. Subsequently 15ml FeCl containing 0.1M concentration were added dropwise3And (3) reacting the solution for 2 hours under the ice-water bath condition to ensure that the aniline is polymerized on the surface of the BC membrane and uniformly coated on the BC fiber. And (3) cleaning the membrane by using 75% (v/v) ethanol and distilled water to obtain the PANI @ BC composite membrane.
(3) Weighing 0.1M AgNO3Dissolving in 50mL deionized water, fillingStirring, mixing, and placing into a container of 1 × 2cm2The PANI @ BC composite membrane is oscillated for 12 hours in a water bath constant temperature oscillator at the temperature of 30 ℃.
(4) 0.5g NaOH and 1.76g L-ascorbic acid were dissolved in 12.5mL deionized water, ice-bathed, stirred well and added with 0.14g NaBH4Mixing thoroughly, adding dropwise into AgNO solution by constant flow pump at 70rpm3In the PANI @ BC composite membrane in the aqueous solution, oscillating for 60min in a water bath constant temperature oscillator at 30 ℃, washing the membrane with deionized water and ethanol, and drying for 2h at 60 ℃ to obtain the Ag/PANI @ BC electrode (the molar concentration ratio of silver ions to a reducing agent is 4:3, the impregnation time is 12h, the reaction time is 60min, the reaction temperature is 30 ℃, and the molar concentration ratio of the silver ions to a stabilizing agent is 1: 2).
Example 7
The copper-based electrode for electrochemical catalysis in the embodiment is composed of a CNT @ BC composite film loaded nano-copper electrode obtained by an impregnation method, the electrode is synthesized by an in-situ catalytic reduction method, and the preparation method comprises the following steps:
(1) using acetobacter xylinum as a strain, performing static culture for 2-4 days to prepare a bacterial cellulose pure film, taking out the pure film, placing the pure film into a sodium hydroxide solution, treating the pure film at 80 ℃ for 2-4 hours, taking out the pure film, and rinsing the pure film with deionized water to be neutral to obtain the pure BC film.
(2) The BC film obtained was cut into 1X 2cm2Prefreezing with liquid nitrogen, and freeze drying at 40 deg.C for 48 hr. And after the freeze drying is finished, soaking the carbon nano tube into 50mL of aqueous solution containing 0.1M of carbon nano tube, dynamically oscillating the carbon nano tube in a constant temperature oscillator at 30 ℃ for 24 hours, and taking the carbon nano tube out to obtain the CNT @ BC composite membrane.
(3) 0.1M of CuSO was weighed4·5H2Dissolving O in 50mL deionized water, stirring, mixing, and adding into 1 × 2cm2The CNT @ BC composite membrane is vibrated for 48 hours at the temperature of 30 ℃ in a water bath constant temperature oscillator.
(4) 0.5g NaOH and 0.88g L-ascorbic acid were dissolved in 12.5mL deionized water, ice-bathed, stirred well and added with 0.14g NaBH4Fully mixing, dripping into a CNT @ BC composite membrane immersed in a copper sulfate solution through a constant flow pump at 70rpm, and carrying out water bath at 30 DEG COscillating for 60min in a constant temperature oscillator, washing the membrane with deionized water and ethanol, and drying for 2h at 60 ℃ to obtain the Cu/CNT @ BC electrode (the molar concentration ratio of copper ions to a reducing agent is 4:3, the immersion time is 48h, the reaction time is 60min, the reaction temperature is 30 ℃, and the molar concentration ratio of copper ions to a stabilizing agent is 1: 1).
Example 8
The copper-based electrode for electrochemical catalysis in the embodiment is composed of a PPy @ BC composite membrane loaded nano-copper electrode which is dynamically cultured in situ, the electrode is synthesized by an in situ catalytic reduction method, and the preparation method comprises the following steps:
(1) acetobacter xylinum is taken as a strain, and a 400mL culture medium is added into a horizontal rotary drum reactor in a sterile workbench for culture for 2-3 days. And taking out the pure BC membrane, placing the pure BC membrane in a sodium hydroxide solution, treating the pure BC membrane for 2-4h at 80 ℃, taking out the pure BC membrane, and rinsing the pure BC membrane to be neutral by using deionized water to obtain the pure BC membrane.
(2) Cutting the BC pure membrane cultured dynamically into 1 × 2cm2Placing on a water absorption filter paper, removing a small amount of free water of the BC membrane, putting the BC membrane into a 150ml cut bottle containing pyrrole monomer with the concentration of 0.1M, and reacting for 2h under the action of magnetic stirring to ensure that the BC membrane fully adsorbs the pyrrole monomer. Subsequently 15ml FeCl containing 0.1M concentration were added dropwise3And (3) reacting the solution for 2 hours under the ice-water bath condition to ensure that the pyrrole is polymerized on the surface of the BC membrane and uniformly coated on the BC fiber. And (3) cleaning the membrane by using 75% (v/v) ethanol and distilled water to obtain the dynamically cultured PPy @ BC composite membrane.
(3) 0.1M of CuSO was weighed4·5H2Dissolving O in 50mL deionized water, stirring, mixing, and adding into 1 × 2cm2The PPy @ BC composite membrane is oscillated for 48 hours in a water bath constant temperature oscillator at the temperature of 30 ℃.
(4) 0.5g NaOH and 1.76g L-ascorbic acid were dissolved in 12.5mL deionized water, ice-bathed, stirred well and added with 0.14g NaBH4Fully mixing, dropwise adding the mixture into a PPy @ BC composite membrane soaked in a copper sulfate solution through a constant flow pump at 70rpm, oscillating the mixture in a water bath constant temperature oscillator at 30 ℃ for 30min, washing the membrane with deionized water and ethanol, and drying the membrane at 60 ℃ for 2h to obtain a Cu/PPy @ BC electrode (molar concentration ratio of copper ions to a reducing agent)Examples are 4: 3; the dipping time is 48 h; the reaction time is 30 min; the reaction temperature is 30 ℃; the molar concentration ratio of the copper ions to the stabilizer is 1: 2. ).
Example 9
The copper-based electrode for electrochemical catalysis in the embodiment is composed of a nano copper electrode loaded on a PANI @ BC composite membrane through dynamic in-situ culture, the electrode is synthesized through an in-situ catalytic reduction method, and the preparation method comprises the following steps:
(1) acetobacter xylinum is taken as a strain, and a 400mL culture medium is added into a horizontal rotary drum reactor in a sterile workbench for culture for 2-3 days. And taking out the pure BC membrane, placing the pure BC membrane in a sodium hydroxide solution, treating the pure BC membrane for 2-4h at 80 ℃, taking out the pure BC membrane, and rinsing the pure BC membrane to be neutral by using deionized water to obtain the pure BC membrane.
(2) Cutting the BC pure membrane cultured dynamically into 1 × 2cm2Placing on a water absorption filter paper, removing a small amount of free water of the BC membrane, putting the BC membrane into a 150ml aniline monomer cut bottle with the concentration of 0.1M, and reacting for 2h under the action of magnetic stirring to ensure that the BC membrane fully adsorbs the aniline monomer. Subsequently 15ml FeCl containing 0.1M concentration were added dropwise3And (3) reacting the solution for 2 hours under the ice-water bath condition to ensure that the aniline is polymerized on the surface of the BC membrane and uniformly coated on the BC fiber. And (3) cleaning the membrane by using 75% (v/v) ethanol and distilled water to obtain the dynamically cultured PANI @ BC composite membrane.
(3) 0.1M of CuSO was weighed4·5H2Dissolving O in 50mL deionized water, stirring, mixing, and adding into 1 × 2cm2The PANI @ BC composite membrane is oscillated for 48 hours in a water bath constant temperature oscillator at the temperature of 30 ℃.
(4) 0.5g NaOH and 1.76g L-ascorbic acid were dissolved in 12.5mL deionized water, ice-bathed, stirred well and added with 0.14g NaBH4The mixed solution is fully mixed, the mixed solution is dripped into a PANI @ BC composite membrane soaked in a copper sulfate solution through a constant flow pump at 70rpm, the mixed solution is vibrated for 90min in a water bath constant temperature oscillator at 30 ℃, then the membrane is washed by deionized water and ethanol, and the washed membrane is dried for 2h at 60 ℃ to obtain a Cu/PANI @ BC electrode (the molar concentration ratio of copper ions to a reducing agent is 4:3, the soaking time is 48h, the reaction time is 90min, the reaction temperature is 30 ℃, and the molar concentration ratio of the copper ions to a stabilizing agent is 1: 2).
Example 10
The copper-based electrode for electrochemical catalysis consists of a CNT @ BC composite membrane loaded nano-copper electrode which is statically cultured in situ, the electrode is synthesized by an in situ catalytic reduction method, and the preparation method comprises the following steps:
(1) the method comprises the steps of taking acetobacter xylinum as a strain, adding a carbon nano tube with the concentration of 0.1M, standing in situ for constant temperature culture for 2-3 days, taking out the CNT @ BC composite membrane, placing the CNT @ BC composite membrane in a sodium hydroxide solution, treating at 80 ℃ for 2-4 hours, taking out, rinsing with deionized water to be neutral, and obtaining the CNT @ BC composite membrane.
(2) 0.1M of CuSO was weighed4·5H2Dissolving O in 50mL of 70% ethanol solution (15mL of deionized water +35mL of ethanol), stirring, mixing, and adding into 1 × 2cm2The CNT @ BC composite membrane is vibrated for 48 hours at the temperature of 30 ℃ in a water bath constant temperature oscillator.
(3) Dissolving 0.5g NaOH in 12.5mL deionized water, ice-cooling, stirring thoroughly, adding 0.14g NaBH4The components are fully mixed, and are dripped into a CNT @ BC composite membrane soaked in a copper sulfate solution through a constant flow pump at 70rpm, the mixture is vibrated for 90min in a water bath constant temperature oscillator at 30 ℃, then the membrane is washed by deionized water and ethanol, and the membrane is dried for 2h at 60 ℃ to obtain a Cu/CNT @ BC electrode (the molar concentration ratio of copper ions to a reducing agent is 4:3, the soaking time is 48h, the reaction time is 90min, the reaction temperature is 30 ℃ and ethanol).
(4) CO is carried out on the prepared Cu/CNT @ BC electrode at different potentials2Electrochemical testing, collecting CO therefrom2The product was electrochemically reduced, the product was measured, and the faradaic efficiency was calculated to obtain fig. 17.
Shown in FIG. 15 is Cu/CNT/@ BCNaBH4It plot of electrodes at different voltages, showing Cu/CNT @ BC as the potential increasesNaBH4The current density of the electrode also gradually increases, and the two show positive correlation.
Shown in FIG. 17 as Cu/CNT/@ BCNaBH4The Faraday efficiency diagram of the electrode under different voltages can be obtained from the diagram, the hydrogen evolution reaction is continuously reduced along with the increase of the potential, the higher overpotential in the reaction process is also continuously reduced, and the reaction products CO and C2H4Is continuously increased in the conversion rate of CO2The utilization rate and the conversion rate of (a) are gradually increased. This indicates that the reaction is carried out with NaBH4The electrode prepared for the reducing agent has the advantages of increased contact specific surface area of carbon dioxide and catalyst, increased catalytic active sites and CO2The utilization rate and the conversion rate are higher. Cu/CNT/@ BCNaBH4Electrode pair H at different voltages2、CO、C2H4The two products have different selectivities, the hydrogen evolution reaction is reduced along with the increase of the voltage, and the product H2The content of (A) is reduced; as the voltage increases, product C2H4The content of (A) is obviously increased; the CO content of the product is 1.5-1.91VRHEGradually increased under voltage at 1.5VRHEThe maximum value is reached.
Shown in FIG. 18 is Cu/CNT @ BCKBH4And Cu/CNT @ BCNaBH4Shows the influence of the reducing agent species on the electrochemically active specific surface area as NaBH4The specific surface area of the electrode prepared by the reducing agent is larger than KBH4An electrode prepared for a reducing agent.
Shown in FIG. 23 is Cu/CNT @ BCKBH4And Cu/CNT @ BCNaBH4From the SEM micrographs, it can be seen that copper-based electrocatalysts prepared with different reducing agents have different micro-morphologies, Cu/CNT @ BCNaBH4The copper catalyst in the electrode has two morphologies, with the plate-like dendritic catalyst having a higher surface area, i.e., having more CO2Catalytic reduction of active sites, and Cu/CNT @ BCKBH4The electrode does not exhibit such morphology.
Table 1 shows that the voltage is 1.5VRHECu/CNT @ BC at voltageKBH4And Cu/CNT @ BCNaBH4The faraday efficiencies and catalytic products of (a) can be seen in fig. 23 and table 1, and more CO can be obtained by effectively regulating and controlling the electrode preparation conditions2A catalytic reduction active site. Thereby improving the catalytic activity of the catalyst and the selectivity of catalytic products and improving the Faraday efficiency of the products.
TABLE 1 Cu/CNT @ BCKBH4And Cu/CNT @ BCNaBH4And its Faraday efficiency
Figure BDA0002704031010000141
Example 11
The copper-based electrode for electrochemical catalysis consists of a porous CNT @ BC composite membrane loaded nano copper electrode, is synthesized by an aqueous solution chemical reduction method, and is prepared by the following steps:
(1) using acetobacter xylinum as a strain, performing static culture for 2-4 days to prepare a bacterial cellulose pure film, taking out the pure film, placing the pure film into a sodium hydroxide solution, treating the pure film at 80 ℃ for 2-4 hours, taking out the pure film, and rinsing the pure film with deionized water to be neutral to obtain the pure BC film.
(2) And (3) dynamically dipping the BC pure film by using a carbon nano tube solution with the concentration of 0.1M, dynamically oscillating in a constant temperature oscillator at 30 ℃ for 24 hours, and taking out to obtain the CNT @ BC composite film.
(3) 0.1M CuCl was weighed2(99%, national pharmaceutical group chemical reagent Co., Ltd., the same below) was dissolved in 50mL of 70% ethanol solution (15mL of deionized water +35mL of ethanol), stirred well, mixed well, and placed in a 1X 2cm cell2The CNT @ BC composite membrane is vibrated for 24 hours at the temperature of 30 ℃ in a water bath constant temperature oscillator.
(4) Dissolving 0.5g NaOH in 12.5mL deionized water, ice-cooling, stirring thoroughly, adding 0.14g NaBH4Fully mixing, dropwise adding the mixture into a CNT @ BC composite membrane soaked in a copper chloride solution through a constant flow pump at 70rpm, oscillating the mixture in a water bath constant temperature oscillator at 30 ℃ for 60min, washing the membrane with deionized water and ethanol, and drying the membrane at 60 ℃ for 2h to obtain a Cu/CNT @ BC electrode (4:3-24h-60min-30 ℃ -ethanol). (the molar concentration ratio of the copper ions to the reducing agent is 4: 3; the immersion time is 24 h; the reaction time is 60 min; the reaction temperature is 30 ℃; ethanol).
Example 12
The copper-based electrode for electrochemical catalysis consists of a porous PPy/CNT @ BC composite membrane loaded nano-copper electrode, the electrode is synthesized by an aqueous solution chemical reduction method, and the preparation method comprises the following steps:
(1) the method comprises the steps of taking acetobacter xylinum as a strain, adding a carbon nano tube with the concentration of 0.1M, standing in situ for constant temperature culture for 2-3 days, taking out the CNT @ BC composite membrane, placing the CNT @ BC composite membrane in a sodium hydroxide solution, treating at 80 ℃ for 2-4 hours, taking out, rinsing with deionized water to be neutral, and obtaining the CNT @ BC composite membrane.
(2) Using acetobacter xylinum as a strain, performing static culture for 2-4 days to prepare a bacterial cellulose pure film, taking out the pure film, placing the pure film into a sodium hydroxide solution, treating the pure film at 80 ℃ for 2-4 hours, taking out the pure film, and rinsing the pure film with deionized water to be neutral to obtain the pure BC film.
(3) Cutting the purified BC membrane into 1 × 2cm2The membrane was placed on a water-absorbent filter paper, a small amount of free water was removed from the BC membrane, and the BC membrane was put into a 150ml notched bottle containing 0.1M pyrrole monomer (chemical purity, national drug group chemical reagents Co., Ltd., the same below) and reacted for 2 hours under magnetic stirring, so that the BC membrane sufficiently adsorbed the pyrrole monomer. Subsequently 15ml FeCl containing 0.1M concentration were added dropwise3(CP, not less than 97.0%, national drug group chemical reagent Co., Ltd., the same below) solution, reacting for 2h under ice water bath condition, polymerizing pyrrole on the surface of BC membrane, and uniformly coating on BC fiber. And (3) cleaning the membrane by using 75% (v/v) ethanol and distilled water to obtain the PPy @ BC composite membrane.
(4) Adopting a carbon nano tube with the concentration of 0.05M, obtaining the CNT @ BC composite film cultured in situ in the rest step (1), and then cutting the CNT @ BC composite film cultured in situ into 1 multiplied by 2cm2Placing the film on absorbent filter paper, removing a small amount of free water of the CNT @ BC composite film, putting the film into a 150ml cut bottle containing pyrrole monomers with the concentration of 0.05M, and reacting for 2 hours under the action of magnetic stirring to ensure that the CNT @ BC composite film fully adsorbs the pyrrole monomers. Subsequently 15ml FeCl containing 0.1M concentration were added dropwise3And (3) reacting the solution for 2 hours under the ice-water bath condition, so that pyrrole is polymerized on the surface of the BC membrane and uniformly coated on the CNT @ BC composite membrane. And (3) cleaning the membrane by using 75% (v/v) ethanol and distilled water to obtain the dynamically cultured PPy/CNT @ BC composite membrane.
Adopting a carbon nano tube with the concentration of 0.05M and the rest conditions are the same as the step (1) to obtain the CNT @ BC composite film cultured in situ, and then cutting the CNT @ BC composite film cultured in situ into 1 multiplied by 2cm2Placing on water-absorbing filter paper, removing a small amount of free water of CNT @ BC composite membrane, placing the BC membrane into a 150ml aniline monomer incision bottle with 0.05M concentrationAnd reacting for 2 hours under the action of magnetic stirring to ensure that the BC film fully adsorbs aniline monomers. Subsequently 15ml FeCl containing 0.1M concentration were added dropwise3And (3) reacting the solution for 2 hours under the ice-water bath condition to ensure that the aniline is polymerized on the surface of the BC membrane and uniformly coated on the BC fiber. And (3) cleaning the membrane by using 75% (v/v) ethanol and distilled water to obtain the dynamically cultured PANI/CNT @ BC composite membrane.
0.1M CuCl was weighed2Dissolving in 50mL of 70% ethanol solution (15mL of deionized water +35mL of ethanol), stirring, mixing, and adding into 1 × 2cm2The PPy/CNT @ BC and PANI/CNT @ BC composite membrane is oscillated for 24 hours in a water bath constant temperature oscillator at the temperature of 30 ℃.
Dissolving 0.5g NaOH in 12.5mL deionized water, ice-cooling, stirring thoroughly, adding 0.14g NaBH4Fully mixing, dropwise adding the mixture into a PPy/CNT @ BC and PANI/CNT @ BC composite membrane soaked in a copper chloride solution through a constant flow pump at 70rpm, oscillating the mixture in a water bath constant temperature oscillator at 30 ℃ for 60min, washing the membrane with deionized water and ethanol, and drying the membrane at 60 ℃ for 2h to obtain a Cu/PPy/CNT @ BC and a Cu/PANI/CNT @ BC electrode (4:3-24h-60 min-30-ethanol). (the molar concentration ratio of the copper ions to the reducing agent is 4: 3; the immersion time is 24 h; the reaction time is 60 min; the reaction temperature is 30 ℃ and ethanol).
Weighing 0.1M AgNO3Dissolving in 50mL of 70% ethanol solution (15mL of deionized water +35mL of ethanol), stirring, mixing, and adding into 1 × 2cm2The PPy/CNT @ BC and PANI/CNT @ BC composite membrane is oscillated for 24 hours in a water bath constant temperature oscillator at the temperature of 30 ℃.
Dissolving 0.5g NaOH in 12.5mL deionized water, ice-cooling, stirring thoroughly, adding 0.14g NaBH4Fully mixing, dropwise adding the mixture into a PPy/CNT @ BC and PANI/CNT @ BC composite membrane soaked in a silver nitrate solution through a constant flow pump at 70rpm, oscillating the mixture in a water bath constant temperature oscillator at 30 ℃ for 60min, washing the membrane with deionized water and ethanol, and drying the membrane at 60 ℃ for 2h to obtain an Ag/PPy/CNT @ BC and an Ag/PANI/CNT @ BC electrode (4:3-24h-60min-30 ℃ -ethanol). (the molar concentration ratio of the copper ions to the reducing agent is 4: 3; the immersion time is 24 h; the reaction time is 60 min; the reaction temperature is 30 ℃ and ethanol).
FIG. 6 shows that A is the flexibility of the PPy/CNT @ BC composite film and B is the flexibility of the PPy @ BC composite film, which indicates that the flexibility of the PPy @ BC composite film is increased by the CNT.
As shown in Table 2, the conductivities of the composite membranes BC, CNT @ BC (step 1), PPy @ BC (step 3) and PPy/CNT @ BC (step 4) are higher than those of the composite membranes PPy/CNT @ BC and PPy @ BC.
TABLE 2 conductivity of BC, CNT @ BC, PPy/CNT @ BC composite films
Figure BDA0002704031010000161
Example 13
The silver-based electrode for electrochemical catalysis in the embodiment is composed of a carbon powder @ BC composite membrane loaded nano-copper electrode for dynamic in-situ culture, the electrode is synthesized by an in-situ catalytic reduction method, and the preparation method comprises the following steps:
(1) acetobacter xylinum is taken as a strain, 200mL of a mixed solution of carbon powder (20-50 microns, 10g, Shanghai Yihui potential) with the concentration of 0.1M and a culture medium is added into a horizontal rotary drum reactor, two drops of Tween 80 are added into a rubber head dropper to serve as a dispersing agent, and the mixture is uniformly mixed and cultured for 24 hours. Continuously adding 200ml of 0.1M carbon powder and fermentation liquor mixed culture medium into a glass fermentation tank through a peristaltic pump in an aseptic working platform, and carrying out subsequent fermentation for 24 h. And (3) taking out the carbon powder @ BC composite membrane, placing the carbon powder @ BC composite membrane in a sodium hydroxide solution, treating the carbon powder @ BC composite membrane for 2-4h at 80 ℃, taking out the composite membrane, and rinsing the composite membrane to be neutral by using deionized water to obtain the carbon powder @ BC composite membrane.
(3) 0.1M of CuSO was weighed4·5H2Dissolving O in 50mL deionized water, stirring, mixing, and adding into 1 × 2cm2The carbon powder @ BC composite membrane is oscillated for 24 hours in a water bath constant temperature oscillator at the temperature of 30 ℃.
(4) 0.5g NaOH and 0.88g L-ascorbic acid were dissolved in 12.5mL deionized water, ice-bathed, stirred well and added with 0.14g NaBH4Mixing thoroughly, adding dropwise into CuSO under constant flow pump at 70rpm4·5H2Carbon powder in O solution @ BC composite membrane and water at 30 DEG COscillating for 60min in a bath constant temperature oscillator, washing the membrane with deionized water and ethanol, and drying for 2h at 60 ℃ to obtain the Cu/carbon powder @ BC electrode (the molar concentration ratio of copper ions to a reducing agent is 4:3, the immersion time is 24h, the reaction time is 60min, the reaction temperature is 30 ℃, and the molar concentration ratio of copper ions to a stabilizing agent is 1: 1).
Comparative example 1
(1) Acetobacter xylinum is taken as a strain, 200mL of mixed solution of carbon powder and culture medium with the concentration of 0.1M is added into a horizontal rotary drum reactor, and the culture is carried out for 24 h. Continuously adding 200ml of 0.1M carbon powder and fermentation liquor mixed culture medium into a glass fermentation tank through a peristaltic pump in an aseptic working platform, and carrying out subsequent fermentation for 24 h. And (3) taking out the carbon powder @ BC composite membrane, placing the carbon powder @ BC composite membrane in a sodium hydroxide solution, treating the carbon powder @ BC composite membrane for 2-4h at 80 ℃, taking out the composite membrane, and rinsing the composite membrane to be neutral by using deionized water to obtain the carbon powder @ BC composite membrane.
(2) 0.1M of CuSO was weighed4·5H2Dissolving O in 50mL deionized water, stirring, mixing, and adding into 1 × 2cm2The carbon powder @ BC composite membrane is oscillated for 24 hours in a water bath constant temperature oscillator at the temperature of 30 ℃.
(3) 0.5g NaOH and 1.76g L-ascorbic acid were dissolved in 12.5mL deionized water, ice-bathed, stirred well and added with 0.14g NaBH4Mixing thoroughly, adding dropwise into CuSO under constant flow pump at 70rpm4·5H2And (2) oscillating the carbon powder @ BC composite membrane in the O solution for 60min in a water bath constant-temperature oscillator at 30 ℃, washing the membrane by using deionized water and ethanol, and drying for 2h at 60 ℃ to obtain the Cu/carbon powder @ BC electrode (the molar concentration ratio of copper ions to a reducing agent is 4:3, the impregnation time is 24h, the reaction time is 60min, the reaction temperature is 30 ℃, and the molar concentration ratio of the copper ions to a stabilizing agent is 1: 2).
(4) According to a carbon dioxide electrochemical reduction catalyst in Chinese patent CN108654623A, a preparation method thereof and a gas diffusion electrode loaded with the catalyst, 2mmol of copper chloride dihydrate and 8mmol of nickel chloride hexahydrate are dissolved in 40mL of deionized water in a beaker, 5mL of concentrated ammonia water is dissolved in 45mL of deionized water, the solution is dropwise added into the beaker until the pH value is 9, the solution is stirred for 4 hours, the solution is centrifugally separated, washed to be neutral by deionized water and absolute ethyl alcohol, and the solution is dried in a drying oven at 60 ℃ to obtain solid powder. And grinding the powder, and then putting the powder into a tubular furnace to heat in the air at 350 ℃ for 3h to obtain the nickel-copper sheet layer double metal oxide (the molar ratio of NiO to CuO is 8:2) serving as the carbon dioxide electrochemical reduction catalyst. Dispersing 5mg of the obtained catalyst into 950 mu L of absolute ethyl alcohol, adding 50 mu L of 5 wt% Nafion solution, performing ultrasonic dispersion for 5 hours to obtain a mixed solution, coating 10 mu L of the mixed solution on carbon cloth with the diameter of 4mm, and drying to obtain the gas diffusion electrode loaded with the carbon dioxide electrochemical reduction catalyst.
FIG. 21 is a LSV diagram of the electrodes of Ni-Cu @ carbon cloth (8:2) and Cu/carbon powder @ BC in comparative example 1, from which the current density of the Cu/carbon powder @ BC electrode is higher than that of the Ni-Cu @ carbon cloth (8:2) electrode; the peak potential of the Cu/carbon powder @ BC electrode is greater than that of a nickel-copper @ carbon cloth (8:2) electrode, which shows that the Cu/carbon powder @ BC electrode prepared by the method has higher electrochemical performance.
Comparative example 2
(1) Acetobacter xylinum is taken as a strain, 200mL of mixed solution of carbon powder and culture medium with the concentration of 0.1M is added into a horizontal rotary drum reactor, and the culture is carried out for 24 h. Continuously adding 200ml of 0.1M carbon powder and fermentation liquor mixed culture medium into a glass fermentation tank through a peristaltic pump in an aseptic working platform, and carrying out subsequent fermentation for 24 h. And (3) taking out the carbon powder @ BC composite membrane, placing the carbon powder @ BC composite membrane in a sodium hydroxide solution, treating the carbon powder @ BC composite membrane for 2-4h at 80 ℃, taking out the composite membrane, and rinsing the composite membrane to be neutral by using deionized water to obtain the carbon powder @ BC composite membrane.
(2) Weighing 0.1M AgNO3Dissolving in 50mL deionized water, stirring, mixing, and adding into 1 × 2cm2The carbon powder @ BC composite membrane is oscillated for 24 hours in a water bath constant temperature oscillator at the temperature of 30 ℃.
(3) 0.5g NaOH and 1.76g L-ascorbic acid were dissolved in 12.5mL deionized water, ice-bathed, stirred well and added with 0.14g NaBH4Mixing thoroughly, adding dropwise into AgNO solution by constant flow pump at 70rpm3Oscillating the carbon powder @ BC composite membrane in the solution for 60min in a water bath constant temperature oscillator at 30 ℃, washing the membrane by deionized water and ethanol, and drying for 2h at 60 ℃ to obtain the Ag/carbon powder @ BC electrode (the molar concentration ratio of silver ions to a reducing agent is 4:3, and the impregnation time is 2: 2)4h, 60min of reaction time, 30 ℃ of reaction temperature and 1:2 of molar concentration ratio of silver ions to the stabilizer).
(4) According to the carbon dioxide electrochemical reduction catalyst in the Chinese patent CN108654623A, the preparation method thereof and the gas diffusion electrode loaded with the catalyst, 9mmol of copper chloride dihydrate and 1mmol of nickel chloride hexahydrate are dissolved in 40mL of deionized water in a beaker, 5mL of concentrated ammonia water is dissolved in 45mL of deionized water, the mixture is dropwise added into the beaker until the pH value is 14, the mixture is stirred for 4 hours, the centrifugal separation is carried out, the mixture is washed to be neutral by the deionized water and absolute ethyl alcohol, and the mixture is dried in a drying box at 60 ℃ to obtain solid powder. And grinding the powder, and then putting the powder into a tube furnace to heat in the air at 750 ℃ for 3h to obtain the nickel-copper sheet layer double metal oxide (the molar ratio of NiO to CuO is 1:9) serving as the carbon dioxide electrochemical reduction catalyst. Dispersing 5mg of the obtained catalyst into 950 mu L of absolute ethyl alcohol, adding 50 mu L of 5 wt% Nafion solution, performing ultrasonic dispersion for 5 hours to obtain a mixed solution, coating 10 mu L of the mixed solution on carbon paper with the diameter of 4mm, and drying to obtain the gas diffusion electrode loaded with the carbon dioxide electrochemical reduction catalyst.
Fig. 22 shows CV graphs of the nickel copper @ carbon paper (1:9) and the Ag/carbon powder @ BC electrode in comparative example 2, and the result also shows that the Ag/carbon powder @ BC electrode prepared by the invention has higher current density.
FIG. 20 shows the LSV plots of the composite films of Cu/CNT @ BC (example 1), Cu/PPy @ BC (example 5), Cu/PANI @ BC (example 9), Cu/PANI/CNT @ BC (example 12), Ag/CNT @ BC (example 2), Ag/PPy @ BC (comparative example 2), Ag/PANI @ BC (example 6), and Ag/PANI/CNT @ BC (example 12), indicating that the current density of the composite films is maximized, and the more conductive material combined with BC the composite electrode the greater the current density, the better the electrochemical performance of the metallic silver catalyst over the metallic copper catalyst.
The conductivity of the composite films, Cu/CNT @ BC (example 1), Cu/PPy @ BC (example 5), Cu/PANI @ BC (example 9), Cu/PANI/CNT @ BC (example 12), Ag/CNT @ BC (example 2), Ag/PPy @ BC (comparative example 2), Ag/PANI @ BC (example 6), and Ag/PANI/CNT @ BC (example 12), is also shown in Table 3, where the conductivity of the composite films is better for metallic silver than for metallic copper, and BC is compounded with a conductive material, in the following order: Cu/CNT @ BC < Ag/PPy @ BC < Cu/PPy @ BC < Cu/PANI @ BC < Ag/CNT @ BC < Cu/PANI/CNT @ BC < Ag/PANI @ BC < Ag/PANI/CNT @ BC.
TABLE 3 conductivity of Cu/CNT @ BC, Cu/PPy @ BC, Cu/PANI/CNT @ BC, Ag/PPy @ BC, Ag/PANI/CNT @ BC composite films
Figure BDA0002704031010000181
Table 4 shows the product selectivity (ethylene) of the composite films of comparative example 1 and comparative example 2, i.e., copper ion versus C, nickel copper @ carbon cloth (comparative example 1; 8:2), Cu/PPy @ BC (comparative example 1), nickel copper @ carbon paper (comparative example 2; 1:9), Ag/PPy @ BC (comparative example 2) at a reaction potential of 1.5V2H4The product of (1) has a selectivity in which Cu/PPy @ BC (comparative example 1) is coupled to C2H4The selectivity is optimal.
TABLE 4 reaction potential 1.5V, electrolyte 0.5M K2HCO3The selectivity of the composite membrane products (ethylene) of nickel copper @ carbon cloth (comparative example 1; 8:2), Cu/PPy @ BC (comparative example 1), nickel copper @ carbon cloth (comparative example 2; 1:9) and Ag/PPy @ BC (comparative example 2) under the conditions of (1).
Figure BDA0002704031010000191

Claims (10)

1. The composite electrode material is characterized in that the electrode material is a bacterial cellulose/conductive material composite film with silver or copper nanoparticles loaded on the surface.
2. The electrode material as claimed in claim 1, wherein the electrode material has a porous structure; the conductive material is one or more of a low-dimensional carbon material LDC, polypyrrole PPy and polyaniline PANI; the bacterial cellulose is one or more of bacterial nano cellulose membrane, bacterial nano cellulose homogenate, bacterial nano cellulose flocculent fiber and sponge bacterial nano cellulose after freeze drying.
3. The electrode material of claim 2, wherein the low-dimensional carbon material LDC is one or more of Carbon Nanotube (CNT), graphene and carbon nanopowder.
4. A method of preparing a composite electrode material, comprising:
(1) immersing the bacterial cellulose/conductive material composite membrane into a copper-containing or silver ion aqueous solution, and carrying out oscillation immersion at the temperature of 30-90 ℃;
(2) and (2) under the ice-water bath condition, uniformly mixing sodium hydroxide, a stabilizer and a reducing agent to obtain a mixed solution, then adding the mixed solution into the copper or silver ion aqueous solution containing the composite membrane in the step (1), oscillating at the temperature of 30-90 ℃, and drying to obtain the electrochemical catalytic electrode.
5. The preparation method according to claim 4, wherein the bacterial cellulose/conductive material composite membrane in the step (1) is a 3D nano network structure; the copper ion-containing aqueous solution is a copper sulfate aqueous solution, a copper chloride aqueous solution or a copper nitrate solution; the silver ion-containing aqueous solution is silver nitrate aqueous solution; the concentration of the copper or silver ion-containing aqueous solution is 0.1-0.4M.
6. The method according to claim 4, wherein the shaking and dipping time in the step (1) is 12 to 48 hours.
7. The preparation method according to claim 4, wherein the stabilizer in the step (2) is one or more of L-ascorbic acid, ethanol and citric acid; the reducing agent is one or two of sodium borohydride and potassium borohydride; the concentration of the reducing agent in the mixed solution is 0.2-0.4M, the concentration of the sodium hydroxide is 1M, and the concentration of the stabilizing agent is 0.2-0.8M.
8. The method according to claim 4, wherein the shaking time in the step (2) is 30 to 90 min; the drying is carried out at 50-90 deg.C for 30-90 min.
9. The preparation method according to claim 4, wherein the molar concentration ratio of the copper or silver ions to the reducing agent is 4: 2-4: 4; the molar concentration ratio of the copper/silver ions to the stabilizer is 2: 1-2: 4.
10. Use of the composite electrode material of claim 1 in carbon dioxide electrocatalysis, fuel cells, photocatalysis or biocatalysis.
CN202011032013.9A 2020-09-27 2020-09-27 Copper/silver-based electrode with conductive bacterial cellulose composite membrane as substrate Active CN112194818B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011032013.9A CN112194818B (en) 2020-09-27 2020-09-27 Copper/silver-based electrode with conductive bacterial cellulose composite membrane as substrate

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011032013.9A CN112194818B (en) 2020-09-27 2020-09-27 Copper/silver-based electrode with conductive bacterial cellulose composite membrane as substrate

Publications (2)

Publication Number Publication Date
CN112194818A true CN112194818A (en) 2021-01-08
CN112194818B CN112194818B (en) 2021-12-21

Family

ID=74006947

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011032013.9A Active CN112194818B (en) 2020-09-27 2020-09-27 Copper/silver-based electrode with conductive bacterial cellulose composite membrane as substrate

Country Status (1)

Country Link
CN (1) CN112194818B (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114518393A (en) * 2022-02-14 2022-05-20 扬州大学 GNP-CNT printed electrode and preparation method and application thereof
CN114686473A (en) * 2022-04-07 2022-07-01 杭州师范大学钱江学院 Shewanella immobilized nano-cellulose composite membrane and application thereof
CN115532310A (en) * 2022-09-26 2022-12-30 上海应用技术大学 Graphene oxide-polypyrrole/silver bifunctional material integrating catalytic degradation and detection, and preparation method and application thereof
CN115650372A (en) * 2022-12-27 2023-01-31 杭州师范大学钱江学院 Method for treating antibiotic wastewater and composite material used by same
CN115869967A (en) * 2022-11-21 2023-03-31 昆明理工大学 Foam copper catalyst with cross-scale pore-size structure and preparation method thereof
CN116676011A (en) * 2023-06-01 2023-09-01 上海船舶工艺研究所(中国船舶集团有限公司第十一研究所) Sustained-release cellulose-cuprous oxide antifouling agent and preparation method and application thereof
CN117646263A (en) * 2023-11-30 2024-03-05 深圳市时利达科技有限公司 Porous heat dissipation conductive cloth of electro-coppering

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105111507A (en) * 2015-09-08 2015-12-02 哈尔滨工业大学 Preparation method and application of bacterial cellulose/polyaniline/carbon nanotube conducting film material
CN105609326A (en) * 2015-12-25 2016-05-25 哈尔滨工业大学 Preparation method and application of polypyrrole/graphene/bacterial cellulose conducting film material
CN109680298A (en) * 2019-02-12 2019-04-26 东华大学 BC film loads Nanometer Copper catalyst electrode and the preparation method and application thereof

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105111507A (en) * 2015-09-08 2015-12-02 哈尔滨工业大学 Preparation method and application of bacterial cellulose/polyaniline/carbon nanotube conducting film material
CN105609326A (en) * 2015-12-25 2016-05-25 哈尔滨工业大学 Preparation method and application of polypyrrole/graphene/bacterial cellulose conducting film material
CN109680298A (en) * 2019-02-12 2019-04-26 东华大学 BC film loads Nanometer Copper catalyst electrode and the preparation method and application thereof

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
BONA KIM: "Silver Nanowire Catalysts on Carbon Nanotubes-Incorporated Bacterial Cellulose Membrane Electrodes for Oxygen Reduction Reaction", 《JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY》 *
蔡志江: "细菌纤维素/银纳米粒子复合多孔支架材料的制备与表征", 《高分子材料科学与工程》 *

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114518393A (en) * 2022-02-14 2022-05-20 扬州大学 GNP-CNT printed electrode and preparation method and application thereof
CN114686473A (en) * 2022-04-07 2022-07-01 杭州师范大学钱江学院 Shewanella immobilized nano-cellulose composite membrane and application thereof
CN115532310A (en) * 2022-09-26 2022-12-30 上海应用技术大学 Graphene oxide-polypyrrole/silver bifunctional material integrating catalytic degradation and detection, and preparation method and application thereof
CN115532310B (en) * 2022-09-26 2023-11-24 上海应用技术大学 Graphene oxide-polypyrrole/silver dual-functional material integrating catalytic degradation and detection as well as preparation method and application thereof
CN115869967A (en) * 2022-11-21 2023-03-31 昆明理工大学 Foam copper catalyst with cross-scale pore-size structure and preparation method thereof
CN115869967B (en) * 2022-11-21 2023-09-08 昆明理工大学 Foam copper catalyst with trans-scale pore diameter structure and preparation method thereof
CN115650372A (en) * 2022-12-27 2023-01-31 杭州师范大学钱江学院 Method for treating antibiotic wastewater and composite material used by same
CN116676011A (en) * 2023-06-01 2023-09-01 上海船舶工艺研究所(中国船舶集团有限公司第十一研究所) Sustained-release cellulose-cuprous oxide antifouling agent and preparation method and application thereof
CN117646263A (en) * 2023-11-30 2024-03-05 深圳市时利达科技有限公司 Porous heat dissipation conductive cloth of electro-coppering
CN117646263B (en) * 2023-11-30 2024-09-13 深圳市时利达科技有限公司 Porous heat dissipation conductive cloth of electro-coppering

Also Published As

Publication number Publication date
CN112194818B (en) 2021-12-21

Similar Documents

Publication Publication Date Title
CN112194818B (en) Copper/silver-based electrode with conductive bacterial cellulose composite membrane as substrate
CN108736031B (en) Self-supporting PtCo alloy nanoparticle catalyst and preparation method and application thereof
CN108823600B (en) Nickel-molybdenum carbide nanoparticle/carbon fiber composite nanomaterial, and preparation method and application thereof
Liu et al. A Janus cobalt nanoparticles and molybdenum carbide decorated N-doped carbon for high-performance overall water splitting
Shi et al. FeNi-functionalized 3D N, P doped graphene foam as a noble metal-free bifunctional electrocatalyst for direct methanol fuel cells
CN104549242B (en) Preparation method of nanometer palladium-graphene three-dimensional porous composite electrocatalyst
CN108940285A (en) A kind of preparation method and application of flexibility electrolysis water catalysis material
CN108722453B (en) Molybdenum phosphide/carbon composite nano material for alkaline electro-catalysis hydrogen evolution
Wang et al. Freestanding non‐precious metal electrocatalysts for oxygen evolution and reduction reactions
CN110767914B (en) Co-N doped porous carbon-coated carbon nanotube core-shell structure catalyst and preparation method and application thereof
CN112264018B (en) Nickel-cobalt oxide nanosheet tubular catalyst and preparation method and application thereof
Li et al. Graphitized carbon nanocages/palladium nanoparticles: Sustainable preparation and electrocatalytic performances towards ethanol oxidation reaction
Hong et al. Nickel supported on Nitrogen-doped biomass carbon fiber fabricated via in-situ template technology for pH-universal electrocatalytic hydrogen evolution
CN104607186B (en) Multiwalled carbon nanotube-loaded PdSn catalyst based on deep eutectic solvent, and preparation method and application of catalyst
Sayed et al. Enhancing the performance of direct urea fuel cells using Co dendrites
Shi et al. Biomass-derived precious metal-free porous carbon: Ca-N, P-doped carbon materials and its electrocatalytic properties
CN105977501A (en) High-performance oxygen reduction MnO2-Mn3O4/carbon nanotube composite catalyst and preparation method and application thereof
Gao et al. In-situ assembly of Cu/CuxO composite with CNT/bacterial cellulose matrix as a support for efficient CO2 electroreduction reaction to CO and C2H4
Song et al. Nickel coating on carbon nanotubes and PProDOT-2CH2SH supported Pt nanoparticles as the electrocatalyst for methanol oxidation reaction
Chen et al. CoS2 nanoparticles grown on Mo2TiC2Tx as an efficient electrocatalyst for hydrogen evolution reaction
CN112246261A (en) Cobalt phosphide graded porous nanowire material and preparation and application thereof
CN107293759A (en) A kind of preparation method of fuel cell oxygen reduction electrocatalyst
CN110354870B (en) Preparation method and application of high-performance silver-doped cobalt sulfide oxygen evolution catalyst
CN116288398A (en) Methanol oxidation electrocatalyst and preparation method and application thereof
CN113774428B (en) Preparation method of efficient cobalt rhodium hydroxide nanoparticle/carbon cloth electrode, product and application thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant