CN113426483A - GQDs/Ce-2MI composite photocatalytic bactericide and preparation and application thereof - Google Patents

GQDs/Ce-2MI composite photocatalytic bactericide and preparation and application thereof Download PDF

Info

Publication number
CN113426483A
CN113426483A CN202110523940.9A CN202110523940A CN113426483A CN 113426483 A CN113426483 A CN 113426483A CN 202110523940 A CN202110523940 A CN 202110523940A CN 113426483 A CN113426483 A CN 113426483A
Authority
CN
China
Prior art keywords
solution
gqds
photocatalytic
preparation
bactericide
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
CN202110523940.9A
Other languages
Chinese (zh)
Other versions
CN113426483B (en
Inventor
张晨诚
王齐
贺琴
毛惠秀
朱建旭
曹奕挺
简育玲
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.)
Zhejiang Gongshang University
Original Assignee
Zhejiang Gongshang 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 Zhejiang Gongshang University filed Critical Zhejiang Gongshang University
Priority to CN202110523940.9A priority Critical patent/CN113426483B/en
Publication of CN113426483A publication Critical patent/CN113426483A/en
Application granted granted Critical
Publication of CN113426483B publication Critical patent/CN113426483B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
    • A01N55/00—Biocides, pest repellants or attractants, or plant growth regulators, containing organic compounds containing elements other than carbon, hydrogen, halogen, oxygen, nitrogen and sulfur
    • A01N55/02—Biocides, pest repellants or attractants, or plant growth regulators, containing organic compounds containing elements other than carbon, hydrogen, halogen, oxygen, nitrogen and sulfur containing metal atoms
    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
    • A01N59/00—Biocides, pest repellants or attractants, or plant growth regulators containing elements or inorganic compounds
    • 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
    • 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
    • B01J31/16—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes
    • B01J31/1691—Coordination polymers, e.g. metal-organic frameworks [MOF]
    • 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
    • B01J31/16—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes
    • B01J31/18—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes containing nitrogen, phosphorus, arsenic or antimony as complexing atoms, e.g. in pyridine ligands, or in resonance therewith, e.g. in isocyanide ligands C=N-R or as complexed central atoms
    • B01J31/1805—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes containing nitrogen, phosphorus, arsenic or antimony as complexing atoms, e.g. in pyridine ligands, or in resonance therewith, e.g. in isocyanide ligands C=N-R or as complexed central atoms the ligands containing nitrogen
    • B01J31/181—Cyclic ligands, including e.g. non-condensed polycyclic ligands, comprising at least one complexing nitrogen atom as ring member, e.g. pyridine
    • B01J31/1815—Cyclic ligands, including e.g. non-condensed polycyclic ligands, comprising at least one complexing nitrogen atom as ring member, e.g. pyridine with more than one complexing nitrogen atom, e.g. bipyridyl, 2-aminopyridine
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/30—Treatment of water, waste water, or sewage by irradiation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/50—Treatment of water, waste water, or sewage by addition or application of a germicide or by oligodynamic treatment
    • 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
    • B01J2531/00—Additional information regarding catalytic systems classified in B01J31/00
    • B01J2531/30—Complexes comprising metals of Group III (IIIA or IIIB) as the central metal
    • B01J2531/38—Lanthanides other than lanthanum
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2303/00—Specific treatment goals
    • C02F2303/04—Disinfection
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2305/00—Use of specific compounds during water treatment
    • C02F2305/10—Photocatalysts
    • 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
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00—Technologies for wastewater treatment
    • Y02W10/30—Wastewater or sewage treatment systems using renewable energies
    • Y02W10/37—Wastewater or sewage treatment systems using renewable energies using solar energy

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Health & Medical Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Water Supply & Treatment (AREA)
  • Environmental & Geological Engineering (AREA)
  • Hydrology & Water Resources (AREA)
  • Agronomy & Crop Science (AREA)
  • Pest Control & Pesticides (AREA)
  • Plant Pathology (AREA)
  • Dentistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Wood Science & Technology (AREA)
  • Zoology (AREA)
  • Environmental Sciences (AREA)
  • Toxicology (AREA)
  • Catalysts (AREA)

Abstract

The invention discloses a GQDs/Ce-2MI composite photocatalytic bactericide as well as preparation and application thereof, wherein the preparation method comprises the following steps: step (1): carrying out hydrothermal reaction on the starch suspension to obtain a GQDs solution; step (2): dispersing Ce salt and the GQDs solution prepared in the step (1) into water to obtain a solution A; dispersing 2-methylimidazole and the GQDs solution prepared in the step (1) in water to obtain a solution B; mixing the solution A and the solution B to obtain a GQDs/Ce-2MI precursor solution; and (3): and (3) standing, washing, vacuum drying and grinding the GQDs/Ce-2MI precursor solution obtained in the step (2) in sequence to obtain the GQDs/Ce-2MI composite photocatalyst. The preparation method is simple and the cost is controllable; the prepared GQDs/Ce-2MI composite photocatalyst has high visible light responsiveness, excellent photocatalytic bactericidal activity and good wastewater treatment effect.

Description

GQDs/Ce-2MI composite photocatalytic bactericide and preparation and application thereof
Technical Field
The invention relates to the technical field of photocatalytic materials, in particular to a preparation method of a novel GQDs/Ce-2MI photocatalytic bactericide and application of the novel GQDs/Ce-2MI photocatalytic bactericide in photocatalytic sterilization.
Background
The photocatalyst technology is an advanced oxidation technology, can excite a photocatalyst to generate electron-hole to destroy a bacterial structure by taking light as a driving force at room temperature, and has a certain sterilization effect. The core of photocatalytic technology in the field of sterilization lies in the preparation and optimization of excellent bactericides. The research field of the existing antibacterial material is rapidly developed, but the research field cannot be satisfied in terms of actual effect, generally the research field can only reach about 70-80%, and the problems of uncontrollable effect, secondary pollution and the like are also caused, so that the development of an environment-friendly material with excellent comprehensive performance, stronger antibacterial performance and stable performance is necessary.
Disclosure of Invention
The invention provides a preparation method of a GQDs/Ce-2MI composite photocatalytic bactericide and application thereof in treatment of wastewater containing E.coli.
A preparation method of GQDs/Ce-2MI photocatalytic bactericide comprises the following steps:
step (1): carrying out hydrothermal reaction on the starch suspension to obtain a GQDs solution;
step (2): dispersing Ce salt and the GQDs solution prepared in the step (1) into water to obtain a solution A; dispersing 2-methylimidazole and the GQDs solution prepared in the step (1) in water to obtain a solution B; mixing the solution A and the solution B to obtain a GQDs/Ce-2MI precursor solution;
and (3): and (3) standing, washing, vacuum drying and grinding the GQDs/Ce-2MI precursor solution obtained in the step (2) in sequence to obtain the GQDs/Ce-2MI composite photocatalyst.
Metal-organic frameworks (MOFs) have received extensive attention and research as an emerging class of hybrid pores. MOFs are connected with metal or metal-oxygen units through organic ligands, and have extremely high specific surface area, abundant topological structures, easily modulated channels and various framework structures, so that the MOFs show potential application prospects in the fields of catalytic molecule identification, adsorption ion exchange, gas storage, biological activity and the like, and the application of the MOFs in the field of photocatalysis is the focus of the invention. As a novel carbon material, the graphene quantum dot has the characteristics of adjustable photoluminescence, good biocompatibility, excellent light stability and the like, and is widely applied to the related fields of photoelectricity, energy and the like. Meanwhile, the Graphene Quantum Dots (GQDs) have good chemical stability and very good visible light absorption and fluorescence characteristics, so that the graphene quantum dots are a very good novel semiconductor material capable of enhancing the photocatalytic capacity of the photocatalyst.
The invention firstly prepares the MOFs material Ce-2MI which takes Ce as a central metal atom, and the photocatalytic activity is not high because the photoproduction electrons and holes of the Ce-2MI are easy to be compounded. The invention then enhances its visible light activity by coupling it to a semiconductor. The Graphene Quantum Dots (GQDs) have good chemical stability, very good visible light absorption and fluorescence characteristics, and are a very good novel semiconductor material capable of enhancing the photocatalytic capacity of the photocatalyst. The photocatalyst is loaded on the surface of a photocatalyst matched with a conduction band, so that the visible light catalytic activity of the catalyst can be obviously improved.
According to the invention, GQDs are loaded by utilizing the high specific surface area of MOFs, and Ce ions are introduced into the MOF center to be combined with an organic ligand to a certain extent, so that the photocatalytic activity of the MOFs material can be greatly improved. By loading the graphene quantum dots, the band gap of the utilized Ce-2MI can be well matched with GQDs, and the visible light catalytic activity of sterilization and bacteriostasis is effectively improved.
Several alternatives are provided below, but not as an additional limitation to the above general solution, but merely as a further addition or preference, each alternative being combinable individually for the above general solution or among several alternatives without technical or logical contradictions.
Uniformly dispersing water-soluble starch in distilled water, and carrying out constant-temperature water bath under continuous stirring to obtain a uniform starch suspension solution; then transferring the obtained uniform starch suspension solution into a high-pressure reaction kettle for constant-temperature hydrothermal treatment; after the hydrothermal reaction is finished, the obtained solution is centrifuged to remove precipitates, and the obtained supernatant is a GQDs solution.
Optionally, in step (1): the concentration of the starch suspension is 5-15 g/L.
Optionally, in step (1): the concentration of the GQDs solution is 1-3 g/L.
Optionally, the heating time of the constant-temperature water bath is 10-50 min; further, heating in a constant-temperature water bath for 20-30 min; most preferably 25 min. Optionally, the temperature of the thermostatic water bath is 60-90 ℃.
Optionally, the temperature of the hydrothermal reaction in the step (1) is 180-220 ℃; the time of the hydrothermal reaction is 30-180 min; furthermore, the time of the hydrothermal reaction is 90-120 min.
Optionally, in step (2): ce in the solution A3+The concentration of (A) is 0.01-0.1 mmol/mL; the concentration of the 2-methylimidazole in the solution B is 0.1-2 mmol/mL; and mixing the solution A and the solution B in equal volume, wherein the dosage of the GQDs solution is determined by the volume ratio of the GQDs solution to the mixed solution in the mixed solution obtained by mixing the solution A and the solution B as 1: 1-1: 50 meters.
When preparing the solution A and the solution B, the volume ratio of the GQDs solution to water may be the same or different, and preferably the same.
Further, the dosage of the GQDs solution is that the volume ratio of the GQDs solution to the mixed solution obtained by mixing the solution A and the solution B is 1: 4-1: 8 counts.
Further, Ce in solution A3+The concentration of (A) is 0.03-0.07 mmol/mL; the concentration of the 2-methylimidazole in the solution B is 0.3-1 mmol/mL.
Further, Ce in solution A3+The concentration of (A) is 0.03-0.07 mmol/mL; the concentration of the 2-methylimidazole in the solution B is 0.3-1 mmol/mL; the volume ratio of the GQDs solution to the solution A in the preparation of the solution A is (0.5-1): 4; the volume ratio of the GQDs solution to the solution B in the preparation of the solution B is (0.5-1): 4; solution A and solution B were mixed in equal volumes.
Most preferably, Ce is in solution A3+The concentration of (A) is 0.05 mmol/mL; the concentration of the 2-methylimidazole in the solution B is 0.5 mmol/mL; the ratio of the volume of the GQDs solution to the volume of the solution A is 1: 4; the ratio of the volume of the GQDs solution used for preparing the solution B to the volume of the solution B is 1: 4; solution A and solution B were mixed in equal volumes. In the mixed solution obtained under the conditions, Ce3+The molar ratio of the 2-methylimidazole to the 2-methylimidazole is 1: 10.
optionally, standing for 20-30 h in the step (3); the vacuum drying temperature is 70-80 ℃; the drying time is 10-12 h. Washing is carried out by adopting ethanol and water respectively.
Optionally, the Ce salt is Ce (NO)3)3。
The invention also provides the GQDs/Ce-2MI photocatalytic bactericide prepared by the preparation method.
The invention also provides a treatment method of the wastewater containing the E.Coli, which comprises the following steps:
and adding the GQDs/Ce-2MI composite photocatalytic bactericide into the wastewater containing E.coli to be treated, stirring in a dark place until the absorption is balanced, and turning on a visible light source for photocatalytic sterilization.
Optionally, the addition amount of the GQDs/Ce-2MI photocatalytic bactericide is 0.1-0.5 g/L.
Optionally, the wavelength of the visible light is 380-840 nm.
The invention aims to provide a preparation method of a novel GQDs/Ce-2MI photocatalytic bactericide, application of the novel GQDs/Ce-2MI photocatalytic bactericide in treatment of wastewater containing E.coli, and application and popularization of the novel GQDs/Ce-2MI photocatalytic bactericide in the field of sterilization. According to the invention, the MOF material and the graphene quantum dots are combined, the advantages of good conductivity, large specific surface area and stable structure of the MOF material and the graphene quantum dots are combined, the visible light response performance of the photocatalytic material is improved while the good sterilization effect is ensured, the separation of photoproduction electrons and holes is accelerated, and the reaction energy consumption is greatly reduced.
Compared with the prior art, the method has at least one of the following beneficial effects:
(1) the GQDs/Ce-2MI composite photocatalyst is simple in preparation method and controllable in cost.
(2) The GQDs/Ce-2MI composite photocatalyst prepared by the method is high in visible light responsiveness, excellent in photocatalytic bactericidal activity and good in wastewater treatment effect;
(3) the GQDs/Ce-2MI composite photocatalyst prepared by the invention has good stability and controllable sterilization effect.
Drawings
FIG. 1 is a photo-current response diagram before and after modification of GQDs/Ce-2MI photocatalytic bactericide in example 1.
FIG. 2 is an AC impedance spectrum before and after modification of the GQDs/Ce-2MI photocatalytic bactericide in example 2.
FIG. 3 is a comparison of the photocatalytic bactericidal performance before and after modification of the GQDs/Ce-2MI photocatalytic bactericide in example 3.
FIG. 4 is a graph showing the comparison of the bactericidal effects of photocatalysts synthesized in example 3 by using 2-MI as an organic ligand and different central metal atoms.
FIG. 5a is a photo comparison of the photo results before and after the photocatalytic sterilization effect of example 5 by adjusting the amount of GQDs added to the Ce-2MI precursor solution.
FIG. 5b is a graph comparing the degradation of the photocatalytic sterilization effect in example 5 by adjusting the amount of GQDs added to the Ce-2MI precursor solution.
FIG. 6 is a comparison of the photocatalytic sterilization performance of example 6 by varying the light irradiation wavelength.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings and embodiments, and it is to be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
In a more preferred embodiment, the preparation method of 20/80GQDs/Ce-2MI photocatalytic bactericide is taken as an example and is explained as follows: the method comprises the following steps:
(1) uniformly dispersing starch in water to obtain a starch solution, wherein the concentration of the starch solution is 10 g/L; heating the obtained starch solution in a constant-temperature water bath at 60 ℃ for 25min while continuously stirring, uniformly stirring, putting into a high-pressure reaction kettle, and carrying out hydrothermal reaction at 200 ℃ for 120 min; after the hydrothermal reaction is finished, the obtained product is kept stand for 24h and then is centrifuged for 30min (the rotating speed is 15000r), and the obtained supernatant is a GQDs solution with the concentration of 2 g/L.
(2) Adding Ce (NO)3)3And (2) uniformly dispersing the GQDs solution prepared in the step (1) in 40mL of water, and uniformly stirring to obtain a solution A; uniformly dispersing 2-methylimidazole and the GQDs solution prepared in the step (1) in 40mL of water, and uniformly stirring to obtain a solution B; dropwise adding the solution B into the solution A, and uniformly stirring and mixing to obtain a GQDs/Ce-2MI precursor solution; wherein the concentration of the cerium nitrate solution in the solution A is 0.05mmol/mL, and the concentration of the 2-methylimidazole solution in the solution B is 0.5 mmol/mL; the mixing volume ratio of the GQDs solution to water when preparing the solution A and the solution B is 1: 4; the mixing ratio of the solution A and the solution B is Ce3+The molar ratio of the 2-methylimidazole to the 2-methylimidazole is 1: in this embodiment, solution A and solution B are mixed in equal volumes.
(3) And (3) standing the GQDs/Ce-2MI precursor solution obtained in the step (2) for 24 hours in sequence, washing for 5 times by using ethanol and water in turn, and drying in vacuum at 70 ℃ to obtain the GQDs/Ce-2MI composite photocatalytic bactericide, namely 20/80GQDs/Ce-2MI, wherein the '20/80' refers to the volume ratio of the GQDs solution in the step (1) to the mixed solution after the solution A and the solution B are mixed in the step (2).
Example 1
Adjusting the dosage of the GQDs solution in the process of preparing the solution A and the solution B in the step (2) of the embodiment, regulating and controlling the content of the loadable GQDs, and preparing powder samples with different load proportions: 2/80GQDs/Ce-2MI, 10/80GQDs/Ce-2MI, 20/80GQDs/Ce-2MI and 40/80GQDs/Ce-2MI, wherein 2/80, 10/80, 20/80 and 40/80 refer to the volume ratio of the GQDs solution in the step (1) to the mixed solution after the solution A is mixed with the solution B.
In order to conveniently detect the photocurrent performance of the catalyst, the powder samples with different loading proportions are prepared into corresponding membrane electrodes by adopting a dripping coating method, the photocurrent is detected to be corresponding, the structure is shown in figure 1, it can be seen from the figure that along with the adjustment of the loading concentration, compared with Ce-2MI, the visible light response of the loaded photocatalytic bactericide GQDs/Ce-2MI is obviously improved, the photoproduction electron-hole has better separation capacity, and the introduction of the GQDs is proved to have certain improvement on the photochemical performance of the Ce-2MI, wherein when the volume ratio of the GQDs solution in the step (1) in the mixed solution of the solution A and the solution B to the mixed solution is 10-20/80, the improvement effect is more obvious, and the optimum is 20/80.
Example 2
Electrochemical impedance spectroscopy, which may also be referred to as ac impedance spectroscopy, is an important tool for studying electrode process dynamics, electrode surface phenomena, and for determining the conductivity of solid electrolytes. The most commonly used in the photocatalytic research is the Nyquist diagram, and the relative size of the radius of the circular arc on the Nyquist diagram corresponds to the size of the charge transfer resistance and the separation efficiency of the photo-generated electron-hole pairs, so as to judge the photocatalytic performance.
FIG. 2 is an ESI Nyquist plot before and after the optimal load of GQDs (20/80GQDs// Ce-2MI), and it can be seen that the radius of the impedance ring after loading is obviously reduced with the aid of visible light, which means that the charge is easier to transfer due to light irradiation. Therefore, GQDs/Ce-2MI prepared by modifying the GQDs have better visible light response performance and have photocatalysis application potential.
Example 3
The actual application effect of the material is tested by the GQDs/Ce-2MI visible light photocatalytic bactericidal activity before and after modification loading. Adding a target photocatalytic bactericide (20/80GQDs// Ce-2MI) into a normal saline solution containing E.coli, after dark reaction adsorption balance, irradiating for 1h under visible light for killing bacteria, sequentially sampling to obtain bacterial suspensions, sequentially diluting the obtained bacterial suspensions by different times, coating 50 mu L of diluent on an agarose culture medium, continuously culturing for 24h in a constant-temperature incubator at the temperature of 37 ℃, and taking out and counting after the culture is finished.
FIG. 3 is a graph of the degradation curve of the photocatalytic bactericide before and after modification on Escherichia coli, and it can be seen more intuitively that 20/80GQDs/Ce-2MI have higher killing rate on Escherichia coli. Meanwhile, 20/80GQDs/Ce-2MI sterilization effect is not obvious in a test under a dark state, and the significance of visible light catalysis is proved.
Example 4
The different central metal atoms and the organic ligand 2-MI can form composite photocatalysts with different central metal atoms. With M (NO)3)X(wherein M is Ce or Fe)2+、Fe3+Co) provides central metal atoms, distilled water is used as a solvent, and a series of photocatalytic sterilizing agents with different central metal atoms are prepared by a one-step method by adopting a method similar to the preparation of GQDs/Ce-2 MI. And the procedure of example 3 was followed, the target photocatalytic bactericide was added to the physiological saline solution containing e.coli, and after adsorption equilibrium in the dark reaction, the bacteria were killed by irradiation for 1 hour under visible light for comparison.
As shown in FIG. 4, it is clear that GQDs/Ce-2MI with Ce as the central metal atom has the best photocatalytic sterilization performance, which is obviously better than other metal atoms.
Example 5
As a MOFs material, Ce-2MI is not high in photocatalytic activity per se; the graphene quantum dots are used as a novel carbon material, and have good chemical stability and very good visible light absorption and fluorescence characteristics; therefore, the method selects to load GQDs on the Ce-2MI to modify the Ce-2 MI. For the modified GQDs/Ce-2MI photocatalytic bactericide prepared by the invention, an important influencing factor is the content of the loaded GQDs. If the concentration of the loaded GQDs is too low, the loaded GQDs cannot be well combined with Ce-2MI, and a good modification effect cannot be achieved; if the concentration of the GQDs is too high, Ce-2MI can be completely wrapped, and the active sites cannot be exposed.
In this example, samples prepared in example 1 at different loading ratios were tested for bactericidal performance using the sterilization method of example 3.
FIG. 5a is a photograph of an agarose medium cultured for 24 hours, and it can be seen that the GQDs/Ce-2MI photocatalytic bactericide prepared when the volume ratio of the GQDs solution to the mixed solution is 20/80 has the best bactericidal effect.
FIG. 5b is the corresponding degradation curve map, and it can be seen that the ratio of GQDs solution to the mixed solution is 10/80 and 20/80, which has higher killing rate to Escherichia coli.
Example 6
In a photocatalytic system, different illumination wavelengths have great influence on the adsorption and photocatalytic effects of a target photocatalyst, the response of Ce-2MI visible light loaded by GQDs is enhanced, the illumination wavelength range is adjusted in the embodiment, and the sterilization performance is tested by adopting the sterilization method in the embodiment 3.
FIG. 6 is a graph showing the killing effect of the optimum ratio GQDs/Ce-2MI photocatalytic bactericide on Escherichia coli under irradiation of visible light of different wavelengths after adsorption equilibrium of dark reaction, and it can be seen that the more remarkable the killing effect is with the increase of the visible light wavelength.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims (10)

1. A preparation method of GQDs/Ce-2MI photocatalytic bactericide is characterized by comprising the following steps:
step (1): carrying out hydrothermal reaction on the starch suspension to obtain a GQDs solution;
step (2): dispersing Ce salt and the GQDs solution prepared in the step (1) into water to obtain a solution A; dispersing 2-methylimidazole and the GQDs solution prepared in the step (1) in water to obtain a solution B; mixing the solution A and the solution B to obtain a GQDs/Ce-2MI precursor solution;
and (3): and (3) standing, washing, vacuum drying and grinding the GQDs/Ce-2MI precursor solution obtained in the step (2) in sequence to obtain the GQDs/Ce-2MI composite photocatalyst.
2. The production method according to claim 1, wherein in step (1): the concentration of the starch suspension is 5-15 g/L; the concentration of the GQDs solution is 1-3 g/L.
3. The production method according to claim 1, wherein in the step (2): ce in the solution A3+The concentration of (A) is 0.01-0.1 mmol/mL; the concentration of the 2-methylimidazole in the solution B is 0.1-2 mmol/mL; and mixing the solution A and the solution B in equal volume, wherein the dosage of the GQDs solution is determined by the volume ratio of the GQDs solution to the mixed solution in the mixed solution obtained by mixing the solution A and the solution B as 1: 1-1: 50 meters.
4. The method according to claim 1, wherein the GQDs solution is used in an amount such that the volume ratio of the GQDs solution to the mixed solution in the mixed solution obtained by mixing solution A and solution B is 1: 4-1: 8 counts.
5. The preparation method according to claim 1, wherein the temperature of the hydrothermal reaction in the step (1) is 180-220 ℃; the time of the hydrothermal reaction is 30-180 min; standing for 20-30 h in the step (3); the vacuum drying temperature is 70-80 ℃; the drying time is 10-12 h.
6. The production method according to claim 1, wherein the Ce salt is Ce (NO)3)3。
7. A GQDs/Ce-2MI photocatalytic bactericide prepared by the preparation method of any one of claims 1-6.
8. A method for treating wastewater containing E.Coli is characterized by comprising the following steps:
adding the GQDs/Ce-2MI composite photocatalytic bactericide as claimed in claim 7 into the wastewater containing E.coli to be treated, stirring in the dark until the adsorption is balanced, turning on a visible light source, and carrying out photocatalytic sterilization.
9. The treatment method according to claim 8, wherein the GQDs/Ce-2MI photocatalytic bactericide is added in an amount of 0.1-0.5 g/L.
10. The method according to claim 8, wherein the wavelength of the visible light is 380 to 840 nm.
CN202110523940.9A 2021-05-13 2021-05-13 GQDs/Ce-2MI composite photocatalytic bactericide and preparation and application thereof Active CN113426483B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110523940.9A CN113426483B (en) 2021-05-13 2021-05-13 GQDs/Ce-2MI composite photocatalytic bactericide and preparation and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110523940.9A CN113426483B (en) 2021-05-13 2021-05-13 GQDs/Ce-2MI composite photocatalytic bactericide and preparation and application thereof

Publications (2)

Publication Number Publication Date
CN113426483A true CN113426483A (en) 2021-09-24
CN113426483B CN113426483B (en) 2022-05-31

Family

ID=77802325

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110523940.9A Active CN113426483B (en) 2021-05-13 2021-05-13 GQDs/Ce-2MI composite photocatalytic bactericide and preparation and application thereof

Country Status (1)

Country Link
CN (1) CN113426483B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114588524A (en) * 2022-03-21 2022-06-07 温州医科大学 Preparation method of soluble microneedle patch constructed based on graphene quantum dots for treating bacterial keratitis
CN115463563A (en) * 2022-09-28 2022-12-13 浙江工商大学 Broad-spectrum response type antibacterial composite membrane and preparation method and application thereof

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109622009A (en) * 2018-12-06 2019-04-16 浙江大学 With Pd@CeO2-CNxThe method of core-shell catalyst catalysis formaldehyde dehydrogenation
CN110038636A (en) * 2019-04-11 2019-07-23 浙江工商大学 A kind of AgI/Ag-Ce-2MI composite photo-catalyst and its preparation and application
CN110302839A (en) * 2019-07-11 2019-10-08 南京工业大学 A kind of smooth fenton catalyst and its preparation method and application
CN110433848A (en) * 2019-08-23 2019-11-12 江南大学 A kind of graphene oxide quantum dot/oxygen doping nitride porous carbon composite photocatalyst

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109622009A (en) * 2018-12-06 2019-04-16 浙江大学 With Pd@CeO2-CNxThe method of core-shell catalyst catalysis formaldehyde dehydrogenation
CN110038636A (en) * 2019-04-11 2019-07-23 浙江工商大学 A kind of AgI/Ag-Ce-2MI composite photo-catalyst and its preparation and application
CN110302839A (en) * 2019-07-11 2019-10-08 南京工业大学 A kind of smooth fenton catalyst and its preparation method and application
CN110433848A (en) * 2019-08-23 2019-11-12 江南大学 A kind of graphene oxide quantum dot/oxygen doping nitride porous carbon composite photocatalyst

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
M. MOTAMEDI: "One-pot synthesis and construction of a high performance metal-organic", 《CHEMICAL ENGINEERING JOURNAL》 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114588524A (en) * 2022-03-21 2022-06-07 温州医科大学 Preparation method of soluble microneedle patch constructed based on graphene quantum dots for treating bacterial keratitis
CN114588524B (en) * 2022-03-21 2023-06-23 温州医科大学 Preparation method of soluble microneedle patch based on graphene quantum dot construction for treating bacterial keratitis
CN115463563A (en) * 2022-09-28 2022-12-13 浙江工商大学 Broad-spectrum response type antibacterial composite membrane and preparation method and application thereof
CN115463563B (en) * 2022-09-28 2023-11-21 浙江工商大学 Broad spectrum response type antibacterial composite film and preparation method and application thereof

Also Published As

Publication number Publication date
CN113426483B (en) 2022-05-31

Similar Documents

Publication Publication Date Title
CN113426483B (en) GQDs/Ce-2MI composite photocatalytic bactericide and preparation and application thereof
Zhang et al. V2O5/Pg-C3N4 Z-scheme enhanced heterogeneous photocatalytic removal of methyl orange from water under visible light irradiation
CN103420452B (en) Bipolar packed bed type three-dimensional electrode photo-electricity catalytic reactor
CN109201065A (en) A kind of nickel foam composite material and preparation method and the application in photoelectrocatalysis removal water pollutant
CN110756203A (en) Ni2P/Mn0.3Cd0.7S photocatalytic water splitting composite catalyst and preparation method and application thereof
CN109317184A (en) Difunctional β-FeOOH/eg-C3N4Composite nano materials and its preparation method and application
CN113600197B (en) Self-gravity-driven high-flux CoAl-LDH and CoAl-LDO catalytic membrane and preparation method thereof
CN111744503A (en) Z-shaped heterojunction MoS2/Bi2WO6Composite photocatalyst and preparation method and application thereof
CN111389469A (en) Preparation method of photocatalytic heterojunction nano composite material for removing algae in water body
CN107416942A (en) A kind of method of microwave radiation technology fast degradation waste water from dyestuff
CN113398989B (en) Organic-inorganic composite material based on PDInH and tungsten oxide and preparation method and application thereof
Tong et al. Preparation and photocatalytic performance of UIO-66/La-MOF composite
CN105597793B (en) A kind of photochemical catalyst and its preparation method and application
CN114314771A (en) Activated blue algae biochar cathode material and application thereof in degradation of antibiotics
CN112237839B (en) Construction method and application of transition metal mediated semi-artificial photosynthesis system
CN111359676B (en) MOF-based composite material and preparation method and application thereof
CN110037052B (en) Photocatalytic bactericide and preparation method and application thereof
CN111408397A (en) Modified carbon nitride and tungsten oxide coupled p-n type heterojunction composite material and preparation method and application thereof
CN108529720B (en) Particle electrode and preparation method and application thereof
CN115414967A (en) Ag @ ZIF-8@ g-C 3 N 4 Composite photocatalyst and preparation method and application thereof
CN110368926B (en) Preparation method of double-Bi defect photocatalyst
CN113832481A (en) Molybdenum trioxide catalyst rich in oxygen defects, preparation method thereof and application thereof in ammonia synthesis
CN113578296A (en) Lamellar gray TiO2 photocatalytic material and preparation method thereof
Chen et al. Critical role of Photo-electrode with Ce-g-C3N4 in multi-stage microbial fuel cells cascade reactor treating diluted hyper-saline industrial wastewater rich in amines
CN115090303B (en) Bi (Bi) 2 S 3 /Bi 5 O 7 I Z heterojunction composite photocatalyst and preparation method 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