CN114804018A - Preparation method of nano metal-graphene composite material - Google Patents
Preparation method of nano metal-graphene composite material Download PDFInfo
- Publication number
- CN114804018A CN114804018A CN202210533671.9A CN202210533671A CN114804018A CN 114804018 A CN114804018 A CN 114804018A CN 202210533671 A CN202210533671 A CN 202210533671A CN 114804018 A CN114804018 A CN 114804018A
- Authority
- CN
- China
- Prior art keywords
- reaction
- composite material
- temperature
- stirring
- nano metal
- 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.)
- Pending
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B3/00—Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
- C01B3/0005—Reversible uptake of hydrogen by an appropriate medium, i.e. based on physical or chemical sorption phenomena or on reversible chemical reactions, e.g. for hydrogen storage purposes ; Reversible gettering of hydrogen; Reversible uptake of hydrogen by electrodes
- C01B3/001—Reversible uptake of hydrogen by an appropriate medium, i.e. based on physical or chemical sorption phenomena or on reversible chemical reactions, e.g. for hydrogen storage purposes ; Reversible gettering of hydrogen; Reversible uptake of hydrogen by electrodes characterised by the uptaking medium; Treatment thereof
- C01B3/0078—Composite solid storage mediums, i.e. coherent or loose mixtures of different solid constituents, chemically or structurally heterogeneous solid masses, coated solids or solids having a chemically modified surface region
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/05—Metallic powder characterised by the size or surface area of the particles
- B22F1/054—Nanosized particles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/12—Metallic powder containing non-metallic particles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/15—Nano-sized carbon materials
- C01B32/182—Graphene
- C01B32/184—Preparation
- C01B32/19—Preparation by exfoliation
- C01B32/192—Preparation by exfoliation starting from graphitic oxides
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/15—Nano-sized carbon materials
- C01B32/182—Graphene
- C01B32/198—Graphene oxide
Abstract
The preparation method comprises the steps of carrying out graphite pre-oxidation, sequentially adding 70-98% concentrated sulfuric acid, potassium persulfate and phosphorus pentoxide into a flask, putting the flask into a high-temperature bath kettle, stirring until the concentrated sulfuric acid, the potassium persulfate and the phosphorus pentoxide are completely mixed, adding graphite powder into the flask, stirring for reaction, diluting, filtering, washing and drying after the reaction is finished to obtain pre-oxidized graphite; reoxidizing pre-oxidized graphite, adding the pre-oxidized graphite and potassium permanganate into sulfuric acid, stirring and mixing in a cold bath, then adjusting the temperature of the cold bath to continuously react, adding deionized water for dilution after the reaction is finished, dropwise adding hydrogen peroxide to remove redundant oxides, standing, taking out a lower-layer precipitate, washing, performing ultrasonic treatment, and drying to obtain graphene oxide; and fully mixing the metal salt ion solution and the graphene oxide, adjusting the mixed solution to be alkaline, adding a reducing agent at room temperature for reduction reaction or reduction in a high-temperature inert atmosphere, and washing and drying after the reaction is finished to obtain the nano metal-graphene composite material.
Description
Technical Field
The invention relates to the technical field of new material hydrogen storage, in particular to a preparation method of a nano metal-graphene composite material.
Background
Graphene is a two-dimensional nanomaterial that stably exists as a single layer of carbon and has excellent properties. Theoretical calculation and experimental exploration prove that the graphene has hydrogen storage capacity, but the graphene has chemical inertia and weak binding force with hydrogen molecules, so that the storage of hydrogen is physical adsorption and the hydrogen storage amount is limited. The method is an effective way for improving the hydrogen storage capacity of the graphene by doping metal on the surface of the graphene with high specific surface area and increasing the active center. The metal nanoparticles are dispersed on the graphene sheet, so that the storage capacity of hydrogen can be effectively increased, and the dispersed nanoparticles enhance the combination between hydrogen and a bottom carbon carrier, so that the hydrogen storage performance of the graphene-nanoparticle composite material can be effectively enhanced. However, since the nanoparticles are difficult to prepare and easy to agglomerate, finding a preparation method of the nanoparticle-graphene composite material with simple preparation process and good dispersibility becomes a key technology for developing the hydrogen storage performance of the graphene-based composite material.
The above information disclosed in this background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is well known to those of ordinary skill in the art.
Disclosure of Invention
The invention aims to provide a preparation method of a nano metal-graphene composite material. The method simply and cheaply combines the graphene with the hydrogen overflow effect to realize the improvement of the hydrogen storage performance of the graphene material. The composite material has good stability, adjustable morphology and structure and good hydrogen storage performance.
In order to achieve the above purpose, the invention provides the following technical scheme:
the preparation method of the nano metal-graphene composite material comprises the following steps:
the first step, pre-oxidizing graphite, sequentially adding a proper amount of concentrated sulfuric acid, potassium persulfate and phosphorus pentoxide into a flask, putting the flask into a high-temperature bath kettle, stirring until the concentrated sulfuric acid, the potassium persulfate and the phosphorus pentoxide are completely mixed, adding graphite powder into the flask, stirring for reaction, and after the reaction is finished, diluting, filtering, washing and drying to obtain pre-oxidized graphite;
secondly, reoxidizing pre-oxidized graphite, adding the pre-oxidized graphite and potassium permanganate into sulfuric acid, stirring and mixing in a cold bath, then adjusting the temperature of the cold bath to continuously react, adding deionized water to dilute after the reaction is finished, dropwise adding hydrogen peroxide to remove redundant oxides, standing, taking out a lower-layer precipitate, washing, performing ultrasonic treatment, and drying to obtain graphene oxide;
and step three, fully mixing the metal salt ion solution and the graphene oxide, adjusting the mixed solution to be alkaline, adding a reducing agent at room temperature for reduction reaction or reduction in a high-temperature inert atmosphere, and washing and drying after the reaction is finished to obtain the nano metal-graphene composite material.
In the preparation method of the nano metal-graphene composite material, in the first step, the mass ratio of the potassium persulfate to the phosphorus pentoxide to the graphite powder is 1:1:3-5:5: 1.
In the preparation method of the nano metal-graphene composite material, in the first step, the heating temperature of a high-temperature bath kettle is 40-90 ℃.
In the preparation method of the nano metal-graphene composite material, in the first step, the reaction time of stirring reaction is 2-8 h.
In the preparation method of the nano metal-graphene composite material, in the second step, the temperature of the cold bath is 0-8 ℃.
In the preparation method of the nano metal-graphene composite material, in the second step, the ultrasonic power is 600W.
In the preparation method of the nano metal-graphene composite material, in the third step, the metal ions contained in the metal salt ion solution include palladium, nickel, ruthenium, magnesium, titanium or vanadium.
In the preparation method of the nano metal-graphene composite material, in the third step, the metal salt ion solution is a palladium acetate solution.
A nano metal-reduced graphene oxide composite material obtained according to the preparation method.
The nano metal-reduced graphene oxide composite material prepared by the preparation method is applied to hydrogen storage.
In the technical scheme, the preparation method of the nano metal-graphene composite material provided by the invention has the following beneficial effects: the preparation method of the nano metal-graphene composite material avoids the reaction of concentrated sulfuric acid and potassium permanganate at high temperature, and reduces the operation risk; the prepared graphene is high in stripping degree, low in layer number and good in stability; the metal salt solution and the graphene oxide homogeneous phase mixed solution are reduced through one-step reaction, so that the dispersion degree of each phase can be greatly improved, and the agglomeration effect is effectively avoided; the method realizes the simultaneous reduction of the graphene oxide and the nano metal by using a high-temperature inert atmosphere method; the method has the advantages of simple process flow, extremely low cost, extremely low energy consumption and low danger coefficient, can be flexibly applied to the loading of other metals, and is easy to realize industrial mass production.
Drawings
In order to more clearly illustrate the embodiments of the present application or technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present invention, and other drawings can be obtained by those skilled in the art according to the drawings.
Fig. 1 is a TEM image of rGO prepared by the method of preparing a nano metal-graphene composite according to example 2 of the present invention;
FIG. 2 is a Raman graph of materials prepared in examples 2 to 5 of the method for preparing a nano metal-graphene composite material according to the present invention;
FIG. 3 is an XRD graph of materials prepared in examples 1 to 5 of the method for preparing a nano metal-graphene composite material according to the present invention;
FIG. 4 is an XRD graph of materials prepared in examples 6 to 8 of the method for preparing a nano metal-graphene composite material according to the present invention;
fig. 5 is a TEM image of a material prepared in example 4 of the method for preparing a nano metal-graphene composite material according to the present invention;
FIG. 6 is a hydrogen adsorption curve diagram of materials prepared in examples 2 to 7 of the method for preparing a nano metal-graphene composite material according to the present invention at a temperature of 77K;
fig. 7 is a schematic view of a material prepared in example 7 of the method for preparing a nano metal-graphene composite material according to the present invention;
fig. 8 is a schematic view of a material prepared in example 8 of the method for preparing a nano metal-graphene composite material according to the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be described in detail and completely with reference to fig. 1 to 8 of the drawings of the embodiments of the present invention, and it is apparent that the described embodiments are a part of the embodiments of the present invention, but not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the equipment or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.
In order to make those skilled in the art better understand the technical solution of the present invention, the present invention will be further described in detail with reference to fig. 1 to 8. A method for preparing a nano metal-graphene composite material comprises the following steps,
the method comprises the following steps of firstly, pre-oxidizing graphite, sequentially adding 70-98% concentrated sulfuric acid, potassium persulfate and phosphorus pentoxide into a flask, putting the flask into a high-temperature bath kettle, stirring until the concentrated sulfuric acid, the potassium persulfate and the phosphorus pentoxide are completely mixed, adding graphite powder into the flask, stirring for reaction, diluting, filtering, washing and drying after the reaction is finished to obtain pre-oxidized graphite;
secondly, reoxidizing graphite, adding the pre-oxidized graphite and potassium permanganate into sulfuric acid, stirring and mixing in a cold bath, then adjusting the temperature of the cold bath to continuously react, adding deionized water to dilute after the reaction is finished, dropwise adding hydrogen peroxide to remove redundant oxides, standing, taking out a lower-layer precipitate, washing, performing ultrasonic treatment, and drying to obtain graphene oxide;
and step three, fully mixing the metal salt ion solution and the graphene oxide, adjusting the mixed solution to be alkaline, adding a reducing agent at room temperature for reduction reaction or reduction in a high-temperature inert atmosphere, and washing and drying after the reaction is finished to obtain the nano metal-graphene composite material.
In a preferred embodiment of the preparation method of the nano metal-graphene composite material, during graphite pre-oxidation, after stirring to be completely mixed, adjusting the temperature for a preset time, adding graphite powder into a flask, stirring to react to obtain a reaction liquid, transferring the reaction liquid into deionized water, stirring, standing, pouring out a supernatant, taking a lower-layer sample, washing to be neutral, and vacuum drying the sample to obtain pre-oxidized graphite.
In the preferred embodiment of the preparation method of the nano metal-graphene composite material, during graphite reoxidation, after stirring and mixing, a flask is transferred to a constant temperature source for reaction, hydrogen peroxide solution is dropwise added to change the solution from reddish brown to golden yellow, the dropwise addition is stopped after the golden yellow is kept changed, after standing, supernatant is poured out, diluted hydrochloric acid and deionized water are used for alternate washing, then, deionized water is used for washing until the solution is neutral, and no sulfate ions exist in the solution.
In the preferred embodiment of the preparation method of the nano metal-graphene composite material, a washed sample is ultrasonically stripped, after the ultrasonic treatment is finished, a supernatant is centrifugally taken, the lower layer suspension is continuously ultrasonically stripped, the supernatant is centrifugally taken, after the supernatant is collected, the graphene oxide is obtained by drying, and the graphene oxide is ground and bottled for later use.
In a preferred embodiment of the method for preparing the nano metal-graphene composite material, graphene oxide is dissolved in deionized water, and a metal salt ion solution is configured based on the load amount.
In a preferred embodiment of the preparation method of the nano metal-graphene composite material, in the first step, the mass ratio of the potassium persulfate to the phosphorus pentoxide to the graphite powder is 1:1:3 to 5:5: 1.
In a preferred embodiment of the method for preparing the nano metal-graphene composite material, in the first step, the heating temperature of the high-temperature bath is 40-90 ℃.
In a preferred embodiment of the preparation method of the nano metal-graphene composite material, in the first step, the reaction time of the stirring reaction is 2-8 h.
In a preferred embodiment of the method for preparing a nano metal-graphene composite material, in the second step, the temperature of the cooling bath is 0 to 8 ℃.
In a preferred embodiment of the method for preparing a nano metal-graphene composite material, in the third step, the metal salt ion solution contains metal ions including palladium, nickel, ruthenium, magnesium, titanium or vanadium.
The preparation method comprises the following steps:
step (1): pre-oxidation stage of graphite
Concentrated sulfuric acid, potassium persulfate and phosphorus pentoxide are sequentially and slowly added into the flask. And (3) putting the flask containing the medicine into a high-temperature bath kettle, stirring the medicine until the medicine is completely mixed, and adjusting the temperature to be stable for a period of time. Then adding graphite powder into the three-neck flask, and stirring for reaction. And after the reaction is finished, transferring the reaction solution into deionized water, stirring, standing, pouring out a supernatant, taking a lower layer sample, and washing to be neutral. And (4) drying the sample in vacuum to obtain a pre-oxidized sample, and bottling for later use.
Step (2): reoxidation stage
Taking sulfuric acid in a flask, placing the flask in a cold bath, adding a pre-oxidized sample, slowly adding potassium permanganate, and stirring for reaction. The flask was transferred to a constant temperature source for reaction, to which deionized water was slowly added for dilution, followed by continued stirring. And transferring the reaction solution into a beaker, slowly dropwise adding a hydrogen peroxide solution while stirring to change the solution from reddish brown to golden yellow, and stopping dropwise adding after the golden yellow is kept changed. After standing overnight, the supernatant was decanted and washed alternately with dilute hydrochloric acid and deionized water. Followed by a further wash with deionized water to neutrality and a check for the absence of sulfate ions in the solution.
And (3) carrying out ultrasonic stripping on the washed sample, centrifuging after the ultrasonic treatment is finished, taking the supernatant, continuously carrying out ultrasonic stripping on the lower suspension, and centrifuging to take the supernatant. And collecting the supernatant, drying to obtain graphene oxide, grinding and bottling for later use.
And (3): and (3) dipping reduction stage:
and (3) dissolving graphene oxide in deionized water, and preparing a metal salt ion solution according to different loading amounts. Slowly dripping the salt solution into the graphene oxide colloid solution, violently stirring, and uniformly dispersing by using ultrasonic after stirring. And pouring the mixed solution into a flask, adjusting the pH value, and putting the flask into a constant-temperature source for later use. Taking deionized water, adjusting the pH value, weighing a reducing agent, and dissolving the reducing agent in the alkaline solution for reaction. And (3) obtaining a precipitate after the reaction is finished, filtering, fully washing the precipitate to be neutral by using deionized water, and drying. Reducing by adding a reducing agent or reducing at high temperature and low vacuum.
Further, in step (1), the sulfuric acid concentration used is 70 to 98%, preferably 98%.
Further, in the step (1), the mass ratio of the potassium persulfate to the phosphorus pentoxide to the graphite powder is 1:1:3-5:5:1, preferably 5:5: 6. The mixed solution can be obtained by adjusting the concentration of potassium persulfate, phosphorus pentoxide, graphite powder and sulfuric acid.
Further, in the step (1), the heating temperature is 40 to 90 ℃, preferably 80 ℃.
Further, in step (1), the reaction time is 2 to 8 hours, preferably 4 hours. The pre-oxidized graphite is obtained after dilution, filtration, washing and drying.
Further, in the step (2), the ratio of the pre-oxidized graphite to the potassium permanganate is 1:1 to 1:10, preferably 1: 5.
Further, in the step (2), the dropping rate is 30 to 150 drops per minute, preferably 60 drops per minute.
Further, in step (2), the ice bath temperature is 0 to 8 ℃, preferably 4 ℃.
Further, in the step (2), the power of the ultrasonic dispersion is 100-800W, preferably 600W.
Further, in the step (3), the metal salt ion solution contains metal ions of palladium, nickel, ruthenium, magnesium, titanium, vanadium, preferably palladium.
Further, in step (3), the pH of the alkaline environment is 8.0 to 11.0, preferably 9.0.
Further, in step (3), the reducing agent used is sodium borohydride, hydrazine hydrate, ascorbic acid, preferably sodium borohydride.
Further, in step (3), the reduction temperature used is 600-1000 ℃, preferably 700 ℃.
Further, in the step (3), the reduction conditions used are low vacuum, i.e., the pressure in the furnace is 0.1Pa to 100Pa, preferably 1 Pa.
In another aspect, the invention further provides a graphene-based composite material prepared by the method, wherein the nano metal particles are uniformly dispersed on the graphene substrate.
In still another aspect, the invention also provides the application of the composite material in hydrogen storage.
As shown in fig. 1 to 8, embodiment 1:
15mL of 98% concentrated sulfuric acid (98% is used as an example here), 2.5g of potassium persulfate, and 2.5g of phosphorus pentoxide were gradually added in this order to a 250mL flask. The flask containing the drug is put into a 90 ℃ oil bath pot, the drug is stirred until the drug is completely mixed, and the temperature is adjusted to 80 ℃ and stabilized for 10 min. Then, 3g of graphite powder (here, 3g of graphite powder is taken as an example, the mass ratio of potassium persulfate, phosphorus pentoxide and graphite powder is 2.5:2.5:3) is slowly added into the three-necked flask, and the reaction is stirred for 4 hours. After the reaction is finished, transferring the reaction solution to a beaker filled with 400mL of deionized water, then adding 100mL of deionized water into the beaker, stirring for 30min, standing overnight, pouring out the supernatant, and taking the lower layer sample and washing to be neutral. And (4) drying the sample in vacuum to obtain a pre-oxidized sample, and bottling the pre-oxidized sample for later use. 36mL of concentrated sulfuric acid (98%) is taken in a flask, the flask is placed in an ice-water bath, 1g of pre-oxidized sample is added, and 1-10g of potassium permanganate (taking 5g of potassium permanganate as an example here) is slowly added to be stirred and reacted for 2 hours. After the reaction was maintained for 8 hours by transferring the flask to a 35 ℃ water bath, 300 and 400mL of deionized water were slowly added thereto for dilution, followed by further stirring for 30 min. And transferring the reaction solution into a 500mL beaker, slowly dropwise adding a 30% hydrogen peroxide solution while stirring to change the solution from reddish brown to golden yellow, and stopping dropwise adding after the golden yellow is kept unchanged for 30 min. After standing overnight, the supernatant was decanted and the lower sample was washed three times with alternating layers of dilute hydrochloric acid and deionized water. Followed by a further wash with deionized water to neutrality and a check for the absence of sulfate ions in the solution. Ultrasonically stripping the washed sample by using an ultrasonic cell wall breaking device 600w, centrifuging for 10min at 3000r/min after the ultrasonic treatment is finished, taking supernatant, continuously ultrasonically stripping the lower suspension, and centrifuging to take supernatant. And collecting the supernatant, and drying to obtain a GO (graphene oxide) brown flocculent sample.
For another example, 25mL of 70% concentrated sulfuric acid, 2.5g of potassium persulfate, and 2.5g of phosphorus pentoxide were added slowly in that order to a 250mL flask. The flask containing the drug is put into a 90 ℃ oil bath pot, the drug is stirred until the drug is completely mixed, and the temperature is adjusted to 80 ℃ and stabilized for 10 min. Then 0.5g of graphite powder (the mass ratio of potassium persulfate to phosphorus pentoxide to the graphite powder is 5:5:1) is slowly added into the three-necked flask, and the mixture is stirred and reacted for 4 hours. After the reaction is finished, transferring the reaction solution to a beaker filled with 400mL of deionized water, then adding 100mL of deionized water into the beaker, stirring for 30min, standing overnight, pouring out the supernatant, and taking the lower layer sample and washing to be neutral. And (4) drying the sample in vacuum to obtain a pre-oxidized sample, and bottling for later use. 36mL of concentrated sulfuric acid (70%) is put in a flask, the flask is placed in an ice-water bath, 1g of pre-oxidized sample is added, 10g of potassium permanganate is slowly added, and the mixture is stirred and reacted for 2 hours. After the reaction was maintained for 8 hours by transferring the flask to a 35 ℃ water bath, 300 and 400mL of deionized water were slowly added thereto for dilution, followed by further stirring for 30 min. And transferring the reaction solution into a 500mL beaker, slowly dropwise adding a 30% hydrogen peroxide solution while stirring to change the solution from reddish brown to golden yellow, and stopping dropwise adding after the golden yellow is kept unchanged for 30 min. After standing overnight, the supernatant was decanted and the lower sample was washed three times with alternating layers of dilute hydrochloric acid and deionized water. Followed by a further wash with deionized water to neutrality and a check for the absence of sulfate ions in the solution. Ultrasonically stripping the washed sample by using an ultrasonic cell wall breaking device 600w, centrifuging for 10min at 3000r/min after the ultrasonic treatment is finished, taking supernatant, continuously ultrasonically stripping the lower suspension, and centrifuging to take supernatant. And collecting the supernatant, and drying to obtain a GO (graphene oxide) brown flocculent sample.
For another example, 25mL of 70% concentrated sulfuric acid, 2.5g of potassium persulfate, and 2.5g of phosphorus pentoxide were added slowly in that order to a 250mL flask. The flask containing the drug is put into a 90 ℃ oil bath pot, the drug is stirred until the drug is completely mixed, and the temperature is adjusted to 80 ℃ and stabilized for 10 min. Then 7.5g of graphite powder (the mass ratio of potassium persulfate to phosphorus pentoxide to the graphite powder is 1:1:3) is slowly added into the three-necked flask, and the mixture is stirred and reacted for 4 hours. After the reaction is finished, transferring the reaction solution to a beaker filled with 400mL of deionized water, then adding 100mL of deionized water into the beaker, stirring for 30min, standing overnight, pouring out the supernatant, and taking the lower layer sample and washing to be neutral. And (4) drying the sample in vacuum to obtain a pre-oxidized sample, and bottling for later use. 36mL of concentrated sulfuric acid (70%) is put in a flask, the flask is placed in an ice-water bath, 1g of pre-oxidized sample is added, 1g of potassium permanganate is slowly added, and the mixture is stirred and reacted for 2 hours. After the flask was transferred to a 35 ℃ water bath to maintain the reaction for 8h, 300-400mL deionized water was slowly added thereto for dilution, followed by stirring for 30 min. And transferring the reaction solution into a 500mL beaker, slowly dropwise adding a 30% hydrogen peroxide solution while stirring to change the solution from reddish brown to golden yellow, and stopping dropwise adding after the golden yellow is kept unchanged for 30 min. After standing overnight, the supernatant was decanted and the lower sample was washed three times with alternating layers of dilute hydrochloric acid and deionized water. Followed by a further wash with deionized water to neutrality and a check for the absence of sulfate ions in the solution. Ultrasonically stripping the washed sample by using an ultrasonic cell wall breaking device 600w, centrifuging for 10min at 3000r/min after the ultrasonic treatment is finished, taking supernatant, continuously ultrasonically stripping the lower suspension, and centrifuging to take supernatant. And collecting the supernatant, and drying to obtain a GO (graphene oxide) brown flocculent sample.
Example 2:
dissolving 1.0g of graphene oxide in 400mL of deionized water, pouring the solution into a flask, dropwise adding ammonia water to adjust the pH value to 11, and placing the flask into a 25 ℃ water bath kettle for later use. And (3) taking 80mL of deionized water, adjusting the pH value to 11 by using concentrated ammonia water, weighing 10g of sodium borohydride, dissolving the sodium borohydride in the alkaline solution, slowly adding the alkaline solution of the sodium borohydride into a flask in a constant-temperature water bath kettle, and stirring for reacting for 24 hours. Obtaining black precipitate after the reaction is finished, filtering, and fully washing the precipitate to be neutral by using deionized water. And transferring the wet filter cake into a mortar for grinding, and then drying the filter cake to obtain a black flocculent rGO sample. The hydrogen storage capacity of the resulting rGO composite was 0.34 wt%.
Example 3:
1.0g of graphene oxide was dissolved in 400mL of deionized water, and 0.05g of palladium acetate yellow powder was weighed into a small amount of ethanol (0.1g of palladium acetate approximately 15-20mL of ethanol). Slowly dropwise adding the palladium acetate ethanol solution into the graphene oxide colloid solution, stirring vigorously for 1h, and uniformly dispersing the liquid for 30min by using an ultrasonic cell wall breaking device after stirring. Pouring the mixed solution into a flask, dropwise adding ammonia water to adjust the pH value to 11, and putting the flask into a water bath kettle at 25 ℃ for standby. And (3) taking 80mL of deionized water, adjusting the pH value to 11 by using concentrated ammonia water, weighing 10g of sodium borohydride, dissolving the sodium borohydride in the alkaline solution, slowly adding the alkaline solution of the sodium borohydride into a flask in a constant-temperature water bath kettle, and stirring for reacting for 24 hours. Obtaining black precipitate after the reaction is finished, and fully washing the precipitate to be neutral by using deionized water after filtration. And transferring the wet filter cake into a mortar for grinding, and then drying the filter cake to obtain a 5 wt% Pd-rGO black flocculent sample. The hydrogen storage capacity to obtain a 5 wt% Pd-rGO composite was 0.44 wt%.
Example 4:
1.0g of graphene oxide was dissolved in 400mL of deionized water, and 0.08g of palladium acetate yellow powder was weighed and dissolved in a small amount of ethanol (15-20 mL of ethanol was required for 0.1g of palladium acetate). Slowly dropwise adding the palladium acetate ethanol solution into the graphene oxide colloid solution, stirring vigorously for 1h, and uniformly dispersing the liquid for 30min by using an ultrasonic cell wall breaking device after stirring. Pouring the mixed solution into a flask, dropwise adding ammonia water to adjust the pH value to 11, and putting the flask into a water bath kettle at 25 ℃ for standby. And (3) taking 80mL of deionized water, adjusting the pH value to 11 by using concentrated ammonia water, weighing 10g of sodium borohydride, dissolving the sodium borohydride in the alkaline solution, slowly adding the alkaline solution of the sodium borohydride into a flask in a constant-temperature water bath kettle, and stirring for reacting for 24 hours. Obtaining black precipitate after the reaction is finished, filtering, and fully washing the precipitate to be neutral by using deionized water. And transferring the wet filter cake into a mortar for grinding, and then drying the filter cake to obtain an 8 wt% Pd-rGO black flocculent sample. The hydrogen storage capacity of the obtained 8 wt% Pd-rGO composite material is 0.56 wt%.
Example 5:
1.0g of graphene oxide was dissolved in 400mL of deionized water, and 0.12g of palladium acetate yellow powder was weighed out and dissolved in a small amount of ethanol (0.1g of palladium acetate approximately 15-20mL of ethanol). Slowly dropwise adding the palladium acetate ethanol solution into the graphene oxide colloid solution, stirring vigorously for 1h, and uniformly dispersing the liquid for 30min by using an ultrasonic cell wall breaking device after stirring. Pouring the mixed solution into a flask, dropwise adding ammonia water to adjust the pH value to 11, and putting the flask into a water bath kettle at 25 ℃ for standby. And (3) taking 80mL of deionized water, adjusting the pH value to 11 by using concentrated ammonia water, weighing 10g of sodium borohydride, dissolving the sodium borohydride in the alkaline solution, slowly adding the alkaline solution of the sodium borohydride into a flask in a constant-temperature water bath kettle, and stirring for reacting for 24 hours. Obtaining black precipitate after the reaction is finished, filtering, and fully washing the precipitate to be neutral by using deionized water. And transferring the wet filter cake into a mortar for grinding, and then drying the filter cake to obtain a black flocculent 12 wt% Pd-rGO sample. The hydrogen storage capacity to obtain a 12 wt% Pd-rGO composite was 0.52 wt%.
Example 6:
1.0g of graphene oxide was dissolved in 400mL of deionized water, the solution was poured into a flask, ammonia was added dropwise to adjust the pH to 11, and the flask was placed in a 25 ℃ oil bath and kept. Using a liquid-transferring gun to extract 1.4mL of hydrazine hydrate (50 wt%) solution, slowly adding the solution into a flask, stirring for reaction for 24h, then adjusting the temperature of an oil bath to 90 ℃, stirring, carrying out reflux reaction for 3h, taking down a reflux device after the reaction is finished, properly cooling the solution, filtering, and repeatedly washing a filter cake to be neutral by using deionized water. And transferring the wet filter cake into a mortar for grinding, and then drying the filter cake to obtain the H-rGO black flocculent sample. The hydrogen storage capacity of the obtained H-rGO composite material is 0.21 wt%
Example 7:
1.0g of graphene oxide was dissolved in 400mL of deionized water, and 0.08g of palladium acetate yellow powder was weighed into a small amount of ethanol (0.1g of palladium acetate approximately 15-20mL of ethanol). Slowly dropwise adding the palladium acetate ethanol solution into the graphene oxide colloid solution, stirring vigorously for 1h, and uniformly dispersing the liquid for 30min by using an ultrasonic cell wall breaking device after stirring. And pouring the mixed solution into a flask, dropwise adding ammonia water to adjust the pH value to 11, and putting the flask into an oil bath kettle at 25 ℃ for later use. Using a liquid-transferring gun to extract 1.4mL of hydrazine hydrate (50 wt%) solution, slowly adding the solution into a flask, stirring for reaction for 24h, then adjusting the temperature of an oil bath to 90 ℃, stirring, carrying out reflux reaction for 3h, taking down a reflux device after the reaction is finished, properly cooling the solution, filtering, and repeatedly washing a filter cake to be neutral by using deionized water. And transferring the wet filter cake into a mortar for grinding, and then drying the filter cake to obtain a black flocculent H-8 wt% Pd-rGO sample. The hydrogen storage capacity of the obtained H-8 wt% Pd-rGO composite material is 0.59 wt%.
Example 8:
0.24g of graphene oxide is dissolved in 30mL of deionized water for later use. Add 150. mu.L of EDA to 15mL of DI water and stir for 15min to mix well. Slowly dropping the EDA solution into 15mL of graphene oxide solution, sealing and stirring for 1h to obtain the EDA graphene oxide mixed solution which is uniformly mixed. And transferring the stirred mixed solution into a closed container, placing the container into an oven heated to 85 ℃, heating for 6 hours, and then automatically cooling. 0.1g of palladium acetate yellow powder was weighed out and dissolved in a small amount of ethanol (0.1g of palladium acetate about 15-20mL of ethanol). Slowly dropwise adding a palladium acetate ethanol solution into the EDA graphene oxide colloid solution after cooling, stirring vigorously for 1h, and uniformly dispersing the liquid for 30min by using an ultrasonic cell wall breaking device after stirring. And (3) freezing the mixed solution in a low-temperature environment, and then placing the mixed solution in a freeze dryer for drying to obtain the flocculent aerogel composite material. Placing the aerogel in a tube furnace, vacuumizing to 0.1-100 Pa (taking vacuumizing to 1Pa as an example), heating to 200 ℃ from room temperature, keeping the temperature for 1-4h, and continuously heating to 700 ℃ and keeping the temperature for 3-6 h. Then obtaining the N-31 wt% Pd-rGO black flocculent aerogel composite material.
Finally, it should be noted that: the embodiments described are only a part of the embodiments of the present application, and not all embodiments, and all other embodiments obtained by those skilled in the art without making creative efforts based on the embodiments in the present application belong to the protection scope of the present application.
While certain exemplary embodiments of the present invention have been described above by way of illustration only, it will be apparent to those of ordinary skill in the art that the described embodiments may be modified in various different ways without departing from the spirit and scope of the invention. Accordingly, the drawings and description are illustrative in nature and should not be construed as limiting the scope of the invention.
Claims (10)
1. A preparation method of a nano metal-graphene composite material is characterized by comprising the following steps:
the method comprises the following steps of firstly, pre-oxidizing graphite, sequentially adding a proper amount of concentrated sulfuric acid, potassium persulfate and phosphorus pentoxide into a container, placing the container in a high-temperature environment, stirring until the concentrated sulfuric acid, the potassium persulfate and the phosphorus pentoxide are completely mixed, adding graphite powder into the container, stirring for reaction, after the solution is fully reacted, diluting, filtering, washing and drying to obtain pre-oxidized graphite;
secondly, reoxidizing pre-oxidized graphite, adding the pre-oxidized graphite and potassium permanganate into sulfuric acid, stirring and mixing at a low temperature environment, then adjusting the environment temperature to continue reaction, adding deionized water to dilute after the reaction is finished, dropwise adding hydrogen peroxide to remove redundant oxides, standing and taking out a lower-layer precipitate after the solution turns to be golden yellow, and washing, ultrasonically treating and drying to obtain graphene oxide;
and step three, fully mixing the metal salt ion solution and the graphene oxide, adjusting the mixed solution to be alkaline, adding a reducing agent at room temperature for reduction reaction or reduction in a high-temperature inert atmosphere, and washing and drying after the reaction is finished to obtain the nano metal-graphene composite material.
2. The preparation method of the nano metal-graphene composite material according to claim 1, wherein in the first step, the mass ratio of the potassium persulfate to the phosphorus pentoxide to the graphite powder is preferably 1:1:3 to 5:5: 1.
3. The method for preparing the nano metal-graphene composite material according to claim 1, wherein in the first step, the heating temperature of the high-temperature bath is 40-90 ℃.
4. The method for preparing the nano metal-graphene composite material according to claim 1, wherein in the first step, the reaction time of the stirring reaction is 2-8 h.
5. The method for preparing nano metal-graphene composite material according to claim 1, wherein in the second step, the temperature of the cooling bath is 0-8 ℃.
6. The method for preparing the nano metal-graphene composite material according to claim 1, wherein in the second step, the ultrasonic power is 600W.
7. The method of claim 1, wherein in the third step, the metal salt ion solution contains metal ions including palladium, nickel, ruthenium, magnesium, titanium or vanadium.
8. The method for preparing the nano metal-graphene composite material according to claim 1, wherein in the third step, the metal salt ion solution is a palladium acetate solution.
9. A nanometal-reduced graphene oxide composite obtained according to the preparation method of any one of claims 1 to 8.
10. Use of the nanometal-reduced graphene oxide composite prepared by the preparation method according to any one of claims 1 to 8 in hydrogen storage.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2022100495634 | 2022-01-17 | ||
| CN202210049563 | 2022-01-17 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114804018A true CN114804018A (en) | 2022-07-29 |
Family
ID=82514804
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210533671.9A Pending CN114804018A (en) | 2022-01-17 | 2022-05-16 | Preparation method of nano metal-graphene composite material |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114804018A (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101575095A (en) * | 2009-05-26 | 2009-11-11 | 北京大学 | Method for preparing graphene |
| CN102568641A (en) * | 2010-12-29 | 2012-07-11 | 海洋王照明科技股份有限公司 | Preparation method for graphene composite material loaded with nano metal particles |
| CN102745675A (en) * | 2012-06-27 | 2012-10-24 | 合肥工业大学 | Preparation method of spinel-type magnetic MFe2O4/graphene composite material |
| US20120294793A1 (en) * | 2011-05-19 | 2012-11-22 | The Governors Of The University Of Alberta | Production of graphene sheets and ribbons |
-
2022
- 2022-05-16 CN CN202210533671.9A patent/CN114804018A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101575095A (en) * | 2009-05-26 | 2009-11-11 | 北京大学 | Method for preparing graphene |
| CN102568641A (en) * | 2010-12-29 | 2012-07-11 | 海洋王照明科技股份有限公司 | Preparation method for graphene composite material loaded with nano metal particles |
| US20120294793A1 (en) * | 2011-05-19 | 2012-11-22 | The Governors Of The University Of Alberta | Production of graphene sheets and ribbons |
| CN102745675A (en) * | 2012-06-27 | 2012-10-24 | 合肥工业大学 | Preparation method of spinel-type magnetic MFe2O4/graphene composite material |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Lui et al. | Flexible, three-dimensional ordered macroporous TiO2 electrode with enhanced electrode–electrolyte interaction in high-power Li-ion batteries | |
| Pang et al. | Design of NiCo2O4 nanoparticles decorated N, S co-doped reduced graphene oxide composites for electrochemical simultaneous detection of trace multiple heavy metal ions and hydrogen evolution reaction | |
| Spinner et al. | Effect of nickel oxide synthesis conditions on its physical properties and electrocatalytic oxidation of methanol | |
| Hong et al. | Carbon coating on lithium iron phosphate (LiFePO4): Comparison between continuous supercritical hydrothermal method and solid-state method | |
| Pallavolu et al. | Self-assembled and highly faceted growth of Mo and V doped ZnO nanoflowers for high-performance supercapacitors | |
| Li et al. | Synthetic control of Prussian blue derived nano-materials for energy storage and conversion application | |
| KR20170003646A (en) | Nitrogen-doped graphene coated nano-sulfur anode composite material, and preparation method and application thereof | |
| CN103241727B (en) | Preparation method of graphene | |
| Lu et al. | Synthesis of boron and nitrogen doped graphene supporting PtRu nanoparticles as catalysts for methanol electrooxidation | |
| CN104069871B (en) | A kind of Pd-Fe/ graphen catalyst removing halo organic wastewater and preparation method thereof | |
| CN103145122A (en) | Preparation method of nitrogen-doped graphene | |
| CN107955598A (en) | A kind of selenizing molybdenum nanometer sheet/nitrogen-doped carbon composite material of core-shell structure and its preparation method and application | |
| CN109261155A (en) | A kind of carbon nano tube/copper zinc alloy composites and its preparation method and application | |
| CN106531990A (en) | Preparation method for graphene composite electrode material for lithium ion battery | |
| CN108598433A (en) | A kind of SnO2The preparation method of/graphene lithium ion battery negative material | |
| CN113353917B (en) | Controllable preparation method of self-supporting two-dimensional mesoporous nano material | |
| Zuo et al. | Z‐scheme modulated charge transfer on InVO4@ ZnIn2S4 for durable overall water splitting | |
| Lin et al. | A novel method to prepare Ti1. 4V0. 6Ni alloy covered with carbon and nanostructured Co3O4, and its good electrochemical hydrogen storage properties as negative electrode material for Ni-MH battery | |
| Rani et al. | WO3 nanocubes for photoelectrochemical water-splitting applications | |
| Guo et al. | MOFs derived Ag/ZnO nanocomposites anode for Zn/Ni batteries | |
| Sun et al. | Regulation preferred crystal plane and oxygen vacancy of CoWO4 with morphology remolding to boost electrochemical performances for battery-supercapacitor hybrid device electrode | |
| CN105529442B (en) | The preparation method of high performance lithium ionic cell cathode material based on germanium nano-particle/Multi-layer graphite compound | |
| CN102504249A (en) | Preparation method of order meso porous manganese dioxide/ conductive polyaniline composite material | |
| Liu et al. | Boosting zinc ion storage performance of sandwich-like V2O5/graphene composite by effectively inhibiting vanadium dissolution | |
| Yue et al. | Three dimensional carbon coated In2S3 nanowires assembled graphene composites as high performance sodium ion battery anode |
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 |