CN107282134B - Graphene-coated ZnO photocatalyst and preparation method thereof - Google Patents
Graphene-coated ZnO photocatalyst and preparation method thereof Download PDFInfo
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Abstract
The invention relates to a graphene-coated ZnO photocatalyst and a preparation method thereof, wherein the ZnO surface is positively charged, and then is compounded with oxygen-containing functional groups with negative charge on graphene oxide to obtain the graphene oxide-coated ZnO photocatalyst. According to the graphene-coated ZnO composite photocatalyst prepared by the invention, as the used graphene has larger sheet diameter and thinner layer number, ZnO is compounded with the graphene in a plane, the stress between the graphene and the ZnO is reduced, and the structure of the graphene can be greatly kept from being damaged. Meanwhile, ZnO and graphene oxide are compounded through electrostatic force self-assembly, so that graphene can be well coated on the surface of ZnO, the contact area between the graphene and ZnO is increased, the agglomeration of the graphene is reduced, the effect between the graphene and the zinc oxide is enhanced, the separation and transmission of photon-generated carriers generated by a ZnO catalyst are facilitated, and the structure can obviously improve the photocatalysis effect.
Description
Technical Field
The invention relates to a photocatalyst and a preparation method thereof, in particular to a graphene-coated ZnO photocatalyst and a preparation method thereof.
Background
Organic dyes and wastewater pollutants are major sources of pollution in the textile, paper, plastic, and other industries. ZnO is an important photocatalyst, has a wider forbidden band width (3.37eV) and larger exciton binding energy (60meV), has stronger sensitivity to light, and is beneficial to photocatalytic degradation of organic matters in wastewater.
The catalytic performance is reduced because excited electrons and holes generated by light excitation ZnO are easily and rapidly recombined and converted into light energy. Therefore, researchers adopt a plurality of methods to inhibit the recombination of the photo-generated electron-hole pairs and widen the photoresponse area, such as controlling the appearance of ZnO, doping other metal ions, compounding with other metals or semiconductors and the like, and the method has a good effect of improving the photocatalytic performance. It is worth mentioning that scientific researchers can remarkably improve the photocatalytic efficiency of ZnO by compounding ZnO and carbon materials (graphene, carbon nanotubes and the like) by a plurality of methods, and the preparation of the photocatalyst by compounding ZnO and graphene becomes a hot spot of current research.
Although many documents report a ZnO/graphene composite photocatalyst and a preparation method thereof, the method still has many problems, such as poor composite effect of ZnO and graphene, existence of a plurality of free graphene in the composite, serious graphene agglomeration phenomenon, serious damage to the graphene structure and the like, and is not beneficial to improvement of the photocatalytic activity.
Disclosure of Invention
In view of the above problems, an object of the present invention is to provide a method for preparing a graphene-coated ZnO photocatalyst, which increases the contact area between graphene and ZnO and improves the recombination effect between graphene and ZnO.
In order to solve the problems, the invention provides a graphene-coated ZnO photocatalyst, wherein the ZnO surface is positively charged, and then is compounded with oxygen-containing functional groups with negative charge on graphene oxide to obtain the graphene oxide-coated ZnO photocatalyst.
Since carbon atom in graphene is sp2The hybrid form forms a planar structure and forms a delocalized large pi bond with a single electron providing the single electron and other carbon atoms on a plane, so that the graphene has good performanceElectron conductive properties and thermal conductive properties. In addition, graphene has a high specific surface area as a two-dimensional material with a thickness of the order of nanometers. When the graphene and ZnO are compounded to carry out photocatalysis on the organic dye, on one hand, the graphene can absorb organic matters, so that the graphene can be better contacted with a catalyst. On the other hand, the graphene can receive and transfer photoexcited electrons, and the recombination probability of photo-generated electron-hole pairs is reduced. The compounding of the graphene and the ZnO also reduces the band gap of the ZnO, widens the light absorption range of the catalyst, and improves the light energy utilization rate, thereby effectively improving the photocatalytic performance of the ZnO. According to the invention, the surface of ZnO is positively charged, so that a good composite effect is formed by electrostatic interaction with oxygen-containing functional groups with negative charge on graphene oxide, and the graphene-coated ZnO photocatalyst provided by the invention has strong photocatalytic performance.
Preferably, ZnO in the graphene-coated ZnO photocatalyst is of a hexagonal sheet structure. The structure of the zinc oxide coated by the graphene is a hexagonal sheet structure, so that the contact area between the zinc oxide and the graphene can be increased.
Preferably, the number of the graphene layers coated outside the ZnO is less than 5.
Preferably, the particle size of the ZnO is 400 nm-1 μm.
Preferably, the ZnO surface is made electropositive by amination of the ZnO surface.
The invention also provides a preparation method of the graphene-coated ZnO photocatalyst, which comprises the following steps:
amination is carried out on the surface of ZnO, so that the surface of ZnO is positively charged, and the ZnO and oxygen-containing functional groups with negative charge on graphene oxide generate electrostatic interaction for compounding, and a graphene oxide coated ZnO compound is obtained;
and heating the obtained graphene oxide coated ZnO compound to 500-800 ℃ in reducing gas, and annealing for 2-3 hours to obtain the graphene coated ZnO photocatalyst. Preferably, the temperature rise rate is 10-20 ℃/min.
Preferably, the preparation of ZnO comprises: mixing N-methylpyrrolidone and deionized water according to the weight ratio of (4-9): 6 mixing to prepare a mixed solvent; mixing 3.5-5.5 g of zinc acetate with 200mL of mixed solvent and stirring for 4-5 hours at 90-98 ℃; and after the reaction is finished, centrifugally washing and drying the product to obtain the ZnO.
Preferably, the preparation and screening of the graphene oxide comprises: the graphene oxide is prepared according to the literature (J.Am.chem.Soc.,2008,130, 5856-; centrifuging the prepared graphene oxide in a centrifuge at a rotating speed of more than or equal to 8000 rpm for 20-30 minutes to obtain an upper graphene oxide solution; and dispersing graphene oxide in deionized water with a certain volume, and carrying out ultrasonic treatment for 0.5-1 hour to obtain a uniformly dispersed graphene oxide aqueous solution with the concentration of 0.5-1.5 mg/mL.
Preferably, the amination comprises: adding ZnO into 3-aminopropyl-trimethoxy silane and absolute ethyl alcohol according to the volume ratio of 1: and (10) carrying out ultrasonic treatment on the mixed solution, heating and stirring the mixed solution at the temperature of 55-65 ℃, reacting for 8-12 hours, then carrying out centrifugal washing on the mixed solution by using absolute ethyl alcohol, and drying the washed solution to obtain the aminated zinc oxide.
Preferably, the amount of 3-aminopropyl-trimethoxysilane relative to ZnO should be sufficient (the concentration of 3-aminopropyl-trimethoxysilane is not greatly affected before and after the reaction).
Preferably, the compounding is to add 5-10 ml of 0.5-1.5 mg/ml graphene oxide aqueous solution and 1.0-2.0 g of aminated zinc oxide into deionized water for ultrasonic treatment, heat and stir at 55-65 ℃ for reaction for 6-10 hours, and then centrifugally wash and dry the reacted suspension to obtain the graphene oxide-coated ZnO compound.
Preferably, the reducing gas is a hydrogen-nitrogen mixed gas or a hydrogen-argon mixed gas, and the molar mass of the hydrogen is 9-11% of the total molar mass of the reducing gas.
Compared with the prior art, the graphene-coated ZnO composite photocatalyst prepared by the invention has the advantages that the used graphene has larger sheet diameter and thinner layer number, ZnO is compounded with the graphene in a plane, the stress between the ZnO and the ZnO is reduced, and the structure of the graphene can be greatly kept from being damaged. Meanwhile, ZnO and graphene oxide are compounded through electrostatic force self-assembly, so that graphene can be well coated on the surface of ZnO, the contact area between the graphene and ZnO is increased, the agglomeration of the graphene is reduced, the effect between the graphene and the zinc oxide is enhanced, the separation and transmission of photon-generated carriers generated by a ZnO catalyst are facilitated, and the structure can obviously improve the photocatalysis effect.
Drawings
FIG. 1 is an AFM (a) topography and (b) cross-sectional analysis of graphene oxide prepared in example 1;
FIG. 2 is an SEM photograph of hexagonal plate-shaped ZnO prepared in example 1;
FIG. 3 is (a) EDS carbon element distribution, (b) SEM and (c-f) TEM images of graphene-coated hexagonal plate-shaped ZnO prepared in example 1;
fig. 4 is a raman spectrum of graphene-coated hexagonal sheet ZnO prepared in example 1;
fig. 5 is a graph of photocatalytic efficiency versus catalytic time for hexagonal plate-shaped ZnO prepared in example 1, graphene-coated hexagonal plate-shaped ZnO, and graphene/hexagonal plate-shaped ZnO mixture powder prepared in comparative example;
fig. 6 is an ultraviolet-visible diffuse reflection spectrum of the hexagonal plate-shaped ZnO and the graphene-coated hexagonal plate-shaped ZnO prepared in example 1;
fig. 7 shows photoluminescence spectra of hexagonal plate-shaped ZnO prepared in example 1 and graphene-coated hexagonal plate-shaped ZnO.
Detailed Description
The following examples further illustrate the invention, it being understood that the following examples are illustrative only and are not limiting of the invention.
According to the invention, the ZnO surface is positively charged, and then is compounded with the oxygen-containing functional group with negative charge on the graphene oxide, so that the graphene oxide-coated ZnO photocatalyst is obtained. And ZnO in the ZnO photocatalyst coated by the graphene can be in a hexagonal sheet structure. The number of the graphene layers coated outside the ZnO is less than 5. As shown in fig. 3, fig. 3a is a graph of EDS carbon element distribution of graphene-coated zinc oxide, and it can be seen that the zinc oxide surface is covered with carbon elements, and the presence of these carbon elements indicates that the ZnO surface has been coated with graphene. Fig. 3b is an SEM image of graphene-coated zinc oxide, from which it can be seen that a thin transparent graphene coating is present on the ZnO surface, and also the warping and wrinkling of the graphene can be seen. Fig. 3c-3f are TEM images of the sample, and from fig. 3c, we can see that very thin graphene is coated on the outer edge of ZnO, and for graphene with few layers, we observe through high-resolution TEM observation, as in fig. 3d and 3f, we respectively observe that single-layer graphene and three-layer graphene are uniformly coated on the surface of ZnO, which shows that the method provided by the present invention can effectively achieve the purpose of coating ZnO with graphene. In FIG. 3e, the interplanar spacing was 0.28nm, and good crystallinity was obtained for the ZnO (100) plane. Wherein the particle size of the ZnO is 400 nm-1 μm. As shown in fig. 2, fig. 2 is an SEM topography of hexagonal plate-shaped zinc oxide prepared in example 1, and it can be seen that zinc oxide has a regular hexagonal plate-shaped structure with a size of 400nm to 1 μm and has a regular hexagonal plate-shaped pattern on one surface, and all surfaces are flat. The shape can enable the graphene to be coated on the surface of ZnO more easily, and compared with the compounding with an irregular curved surface, the compounding of the graphene and a ZnO plane can reduce the stress between the graphene and the ZnO plane, reduce the damage to the graphene structure and further enhance the interaction between the graphene and the ZnO plane.
According to the invention, the ZnO surface is aminated and then fully reacted with graphene oxide to obtain the graphene oxide coated ZnO compound. And then annealing the obtained graphene oxide coated ZnO compound in a reducing atmosphere to finally obtain the graphene coated ZnO photocatalyst. The following exemplary description is provided for a method for preparing a graphene-coated ZnO composite photocatalyst according to the present invention.
And (3) preparing ZnO. Mixing N-methylpyrrolidone and deionized water according to the weight ratio of (4-9): 6 mixing to prepare a mixed solvent; mixing a proper amount of zinc acetate with 200mL of mixed solvent, and stirring for 4-5 hours at 90-98 ℃; and after the reaction is finished, centrifugally washing and drying the product to obtain the ZnO. As an example, N-methylpyrrolidone (NMP) is mixed with deionized water in a ratio of 1:1 to prepare a mixed solvent; mixing 3.5-5.5 g of zinc acetate with 200mL of mixed solvent and stirring for 4 hours at 95 ℃; and after the reaction is finished, centrifugally washing the product, and drying at 80 ℃ for 10-12 hours.
And (3) preparing graphene oxide. The graphene oxide in the invention can be prepared according to the literature (J.Am.chem.Soc.,2008,130, 5856-.
And (4) screening graphene oxide. And (3) centrifuging the prepared graphene oxide, and preparing graphene oxide aqueous solutions with different concentrations according to requirements. As an example, the prepared graphene oxide is centrifuged in a centrifuge at a rotating speed of more than or equal to 8000 rpm for 20-30 minutes to obtain an upper graphene oxide solution. And dispersing graphene oxide in deionized water with a certain volume, and carrying out ultrasonic treatment for 1 hour to obtain a uniformly dispersed graphene oxide aqueous solution with the concentration of 0.5-1.5 mg/mL.
And amination is carried out on the surface of ZnO. Adding ZnO into 3-aminopropyl-trimethoxy silane and absolute ethyl alcohol according to the volume ratio of 1: and (10) carrying out ultrasonic treatment on the mixed solution, heating and stirring the mixed solution at the temperature of 55-65 ℃, reacting for 8-12 hours, then carrying out centrifugal washing on the mixed solution by using absolute ethyl alcohol, and drying the washed solution to obtain the aminated zinc oxide. Wherein the amount of the 3-aminopropyl-trimethoxysilane relative to ZnO is sufficient (the concentration of 3-aminopropyl-trimethoxysilane before and after the reaction is not greatly affected). According to the invention, the hexagonal sheet ZnO surface is aminated, so that the ZnO surface has electropositivity, and thus the ZnO surface and oxygen-containing functional groups with electronegativity on graphene oxide generate an electrostatic effect, and the composite effect is improved. As an example, hexagonal plate-shaped ZnO is added into a mixed solution of 3-aminopropyl-trimethoxy silane and absolute ethyl alcohol, ultrasonic treatment is carried out for 5-10 minutes, then stirring is carried out for 10 hours at 55-65 ℃, centrifugal washing is carried out on absolute ethyl alcohol after full reaction, and drying is carried out for 10-12 hours at 80 ℃ to obtain aminated zinc oxide.
And preparing a graphene oxide coated ZnO compound. Adding 5-10 ml of 0.5-1.5 mg/ml graphene oxide aqueous solution and 1.0-2.0 g of aminated zinc oxide into deionized water for ultrasonic treatment, heating and stirring at 55-65 ℃ for reaction for 6-10 hours, and then centrifugally washing and drying the reacted suspension to obtain the graphene oxide-coated ZnO composite. The graphene and the ZnO photocatalyst are compounded, so that the sewage can be more effectively treated. Firstly, the large specific surface area of the graphene can well adsorb organic pollutants, so that the photocatalytic efficiency of the catalyst is improved. The light absorption rate of the catalyst can be improved by compounding the graphene and the ZnO, so that the utilization efficiency of light is improved. More importantly, the graphene can be used as an electron acceptor to receive photoexcited electrons generated on the ZnO, so that the probability of electron-hole recombination is reduced, and the catalytic effect is improved (see fig. 6 and 7). As an example, 5-10 mL of 0.5-1.5 mg/mL graphene oxide aqueous solution and 1.0-2.0 g aminated zinc oxide are added into 200mL deionized water, stirred for 6-10 hours at 55-65 ℃ after ultrasonic treatment, and then suspension after reaction is centrifugally washed and dried to obtain the graphene oxide-coated hexagonal sheet ZnO composite. Wherein, the drying can be drying for 10-12 hours at 80 ℃.
The graphene oxide is reduced by using reducing gas at high temperature (for example, 500-800 ℃), so that the aim of preparing the graphene-coated ZnO composite photocatalyst is fulfilled. The reducing gas is mixed gas of hydrogen and nitrogen or mixed gas of hydrogen and argon, and the molar mass of the hydrogen is 9-11% of the total molar mass of the reducing gas. For example, hydrogen nitrogen (H)2:N21:9) mixed gas or hydrogen argon (H)2Ar is 1: 9). As an example, graphene oxide is coated on a hexagonal sheet-shaped ZnO composite in hydrogen nitrogen (H)2:N21:9) heating to 500-800 ℃ at a heating rate of 10-20 ℃/min in a reducing atmosphere of mixed gas, and annealing for 2-3 hours to finally obtain the graphene-coated hexagonal-prism-shaped ZnO photocatalyst.
The present invention will be described in detail by way of examples. It is also to be understood that the following examples are illustrative of the present invention and are not to be construed as limiting the scope of the invention, and that certain insubstantial modifications and adaptations of the invention by those skilled in the art may be made in light of the above teachings. The specific process parameters and the like of the following examples are also only one example of suitable ranges, i.e., those skilled in the art can select the appropriate ranges through the description herein, and are not limited to the specific values exemplified below.
Example 1
Adding 4.50g of zinc acetate, 100mL of N-methylpyrrolidone (NMP) and 100mL of deionized water into a 250mL conical flask, stirring for 4 hours at 95 ℃, centrifugally cleaning a product after the reaction is finished, and drying for 10 hours at 80 ℃ in a drying oven to obtain hexagonal-prism-shaped ZnO.
Putting 1.5g of the hexagonal-prism-shaped ZnO into a 250mL conical flask, adding 5mL of 3-aminopropyl-trimethoxy silane (APTMS) and 95mL of absolute ethyl alcohol, carrying out ultrasonic treatment for 5 minutes, and stirring at 60 ℃ for 10 hours; after the reaction is finished, the product is centrifugally washed by absolute ethyl alcohol and dried for 10 hours at 80 ℃ to obtain the aminated zinc oxide.
Preparing the graphene oxide from the crystalline flake graphite by adopting a modified Hummers method according to a document (J.Am.chem.Soc.,2008,130, 5856-; centrifuging the prepared graphene oxide in a centrifuge at the rotating speed of 8000 rpm for 30 minutes, taking the upper layer solution to disperse in deionized water with a certain volume, and performing ultrasonic treatment for 30 minutes to prepare a uniformly dispersed graphene oxide aqueous solution with the concentration of about 1.0 mg/mL.
Adding 5mL of the graphene oxide solution and 1.5g of the obtained aminated ZnO into 200mL of deionized water, carrying out ultrasonic treatment for 10 minutes, and then stirring at 60 ℃ for 6 hours; and (4) centrifugally washing the reacted suspension, and drying at 80 ℃ for 10 hours to obtain the graphene oxide coated hexagonal flaky ZnO compound.
The obtained graphene oxide-coated hexagonal sheet-shaped ZnO compound was subjected to a reducing atmosphere (hydrogen nitrogen (H) in a tube furnace2:N21:9) mixed gas or hydrogen argon (H)2Ar 1:9) mixed gas) is annealed. And raising the temperature to 550 ℃ at the temperature raising rate of 20 ℃/min, and annealing for 2 hours to finally obtain the graphene-coated hexagonal-prism-shaped ZnO photocatalyst.
Comparative example zinc oxide was not aminated and composited with graphene.
Adding 4.50g of zinc acetate, 100mL of N-methylpyrrolidone (NMP) and 100mL of deionized water into a 250mL conical flask, stirring for 4 hours at 95 ℃, centrifugally cleaning a product after the reaction is finished, and drying for 10 hours at 80 ℃ in a drying oven to obtain hexagonal-prism-shaped ZnO.
Preparing the graphene oxide from the crystalline flake graphite by adopting a modified Hummers method according to a document (J.Am.chem.Soc.,2008,130, 5856-; centrifuging the prepared graphene oxide in a centrifuge at the rotating speed of 8000 rpm for 30 minutes, taking the upper layer solution to disperse in deionized water with a certain volume, and performing ultrasonic treatment for 30 minutes to prepare a uniformly dispersed graphene oxide aqueous solution with the concentration of about 1.0 mg/mL.
Adding 5mL of the graphene oxide solution and 1.5g of the hexagonal flaky ZnO into 200mL of deionized water, carrying out ultrasonic treatment for 10 minutes, and then stirring at 60 ℃ for 6 hours; and (4) centrifugally washing the reacted suspension, and drying at 80 ℃ for 10 hours to obtain graphene oxide/hexagonal sheet ZnO mixture powder.
The obtained graphene oxide/hexagonal sheet-like ZnO mixture powder was subjected to a reducing atmosphere (hydrogen nitrogen (H) in a tube furnace2:N21:9) mixed gas or hydrogen argon (H)2Ar 1:9) mixed gas) is annealed. Heating to 550 ℃ at the heating rate of 20 ℃/min, and annealing for 2 hours to finally obtain the graphene/hexagonal flaky ZnO mixture powder.
The specific steps of the photocatalysis methyl blue are as follows:
preparing 10mg/L Methyl Blue (MB) solution by deionized water, placing 100mL into a beaker, adding 20mg of catalyst, carrying out ultrasonic homogenization, and then carrying out magnetic stirring for 1 hour in a dark place to enable the solution to reach the adsorption-desorption balance. The photocatalytic degradation process is carried out in a catalytic device, a 300W xenon lamp is used as a light source to carry out photocatalytic degradation on the methyl blue solution, a magnetic stirrer is used for continuously stirring, sampling and testing are carried out every 10min, supernatant liquid is taken after centrifugal separation, and the absorbance of the methyl blue solution at the maximum absorption wavelength is measured by an ultraviolet visible spectrophotometer. The degradation efficiency can be represented by the following sub-formula:
characterization of the samples
An Atomic Force Microscope (AFM) is the most effective tool for detecting graphene, and the size and the number of layers of the graphene sheet diameter can be visually seen through the appearance test of the AFM on the graphene. We characterized the surface of the prepared and screened graphene oxide, as shown in fig. 1, fig. 1 is an afm (a) topography and (b) cross-sectional analysis of the prepared graphene oxide prepared in example 1, and it can be seen that most of the graphene oxide has a thickness of not more than 3 layers and a thickness of not more than 5 layers, and the sheet diameter of the graphene oxide is less than 300 nm.
FIG. 4 is a Raman spectrum of the graphene-coated hexagonal plate-shaped ZnO prepared in example 1, in which a D peak and a G peak of the graphene can be clearly seen, and an intensity ratio I of the D peak to the G peakD/IG＝0.91<1, the defect of the graphene is less, the structure is more complete, and sp with a larger area is shown2And (3) components.
Photocatalytic experiment
Fig. 5 is a graph of the concentration percentage of methyl blue in a photocatalytic methyl blue experiment as a function of time, and we performed a photocatalytic experiment test on the hexagonal plate-shaped ZnO prepared in example 1, the graphene-coated hexagonal plate-shaped ZnO, and the graphene/hexagonal plate-shaped ZnO mixture powder prepared in a comparative example. As can be seen from the figure, the catalytic efficiency of the graphene-coated hexagonal platelet-shaped zinc oxide (ZnO @ Gr) was greatly improved compared to the prepared hexagonal platelet-shaped ZnO. At 50 minutes, the ZnO catalyst degraded only 61%, while the graphene-coated hexagonal platelet-shaped ZnO degraded methyl blue almost completely. The composition of the graphene and the ZnO plays an important role in improving the photocatalytic efficiency. The photocatalytic efficiency of the graphene/hexagonal flaky ZnO mixture powder (unmodified ZnO/Gr) which is not prepared by ZnO surface amination in 50 minutes is 41.3 percent, which is far lower than ZnO @ Gr prepared by ZnO surface amination, even lower than hexagonal flaky ZnO which is not compounded with graphene. This shows that not only the composite effect of ZnO and graphene is poor in the unmodified ZnO/Gr, but also the existence of graphene in the powder absorbs much light energy, and the effect of ZnO and light is reduced, so that the photocatalytic efficiency is even lower than that of hexagonal sheet ZnO. In addition, due to the existence of graphene, ZnO @ Gr and unmodified ZnO/Gr both show stronger adsorption capacity to methyl blue.
Mechanism for improving photocatalytic performance
As can be seen from FIG. 5, ZnO @ Gr has a strong adsorption effect on methyl blue in the photocatalysis process, so that the ZnO @ Gr can have a better contact effect with the methyl blue, and when light acts on a catalyst, a photoexcited carrier can more easily act on the methyl blue to degrade the methyl blue. And when the methyl blue adsorbed on the catalyst is degraded, the catalyst continuously adsorbs the methyl blue in the solution, so that the catalyst is continuously in an adsorption-desorption equilibrium state.
FIG. 6 is a sample UV-visible diffuse reflectance spectrum calculated (α h v)2The-hv curve can show that the band gaps of the ZnO and the ZnO @ Gr prepared in the embodiment 1 are respectively 3.26 eV and 3.22eV, and the cladding of the visible graphene reduces the band gap of the ZnO, so that the excitation wavelength of photo-generated electrons is reduced, the ZnO can generate photo-excited carriers more easily, and the photocatalytic rate of the ZnO is further improved. As can be seen from the ultraviolet visible diffuse reflection spectrum, compared with ZnO, the light absorption of ZnO @ Gr has obvious red shift and the absorptivity of the ZnO @ Gr is increased in visible and near ultraviolet bands, so that the light sensing range of the compound is widened, and the light utilization rate of the catalyst can be improved.
Fig. 7 is a photoluminescence spectrum of ZnO and ZnO @ Gr prepared in example 1, wherein near-ultraviolet light with a wavelength of 398nm is generated by photo-excited recombination of electrons and holes, and when the recombination probability of the photo-generated electron-hole pairs is higher, the generated luminescence intensity is higher, and the recombination of the photo-generated electrons and holes reduces the number of high-energy electrons and holes, which is not beneficial to catalysis of the catalyst on methyl blue. The photoluminescence intensity graph shows that the photoluminescence intensity of the hexagonal-prism-shaped ZnO coated by the graphene is greatly reduced, which shows that the probability of recombination of photogenerated electrons and holes in the compound is greatly reduced, and the photogenerated carriers are effectively separated. The graphene can be used for bearing the receiving and transmitting functions of electrons, light-excited electrons generated on the surface of ZnO are transferred to the graphene, and the graphene has a good conduction function on the electrons, so that the electrons can be rapidly transmitted, and the electrons and holes can be effectively separated.
Claims (3)
1. The preparation method of the graphene-coated ZnO photocatalyst is characterized in that the ZnO surface is positively charged and then is compounded with oxygen-containing functional groups with negative charge on graphene oxide to obtain the graphene oxide-coated ZnO photocatalyst; ZnO in the ZnO photocatalyst coated by the graphene is in a hexagonal sheet structure;
the preparation method of the graphene-coated ZnO photocatalyst comprises the following steps:
amination is carried out on the surface of ZnO, so that the surface of ZnO is positively charged, and the ZnO and oxygen-containing functional groups with negative charge on graphene oxide generate electrostatic interaction for compounding, and a graphene oxide coated ZnO compound is obtained; the compounding is that 5-10 mL of 0.5-1.5 mg/mL graphene oxide aqueous solution and 1.0-2.0 g aminated zinc oxide are added into deionized water for ultrasonic treatment, and the mixture is heated and stirred at 55-65 ℃ for reaction for 6-10 hours; the amination comprises: adding ZnO into 3-aminopropyl-trimethoxy silane and absolute ethyl alcohol according to the volume ratio of 1: (10-20), carrying out ultrasonic treatment on the mixed solution, heating and stirring the mixed solution at 55-65 ℃, reacting for 8-12 hours, then carrying out centrifugal washing on the mixed solution by using absolute ethyl alcohol, and drying the washed solution to obtain aminated zinc oxide;
heating the obtained graphene oxide coated ZnO compound to 500-800 ℃ in reducing gas, and annealing for 2-3 hours to obtain a graphene coated ZnO photocatalyst; the number of the graphene layers coated outside the ZnO is less than 5, and the particle size of the ZnO is 400 nm-1 mu m.
2. The method according to claim 1, wherein the ZnO preparation comprises: mixing N-methylpyrrolidone and deionized water according to the weight ratio of (4-9): 6 mixing to prepare a mixed solvent; mixing 3.5-5.5 g of zinc acetate with 200mL of mixed solvent and stirring for 4-5 hours at 90-98 ℃; and after the reaction is finished, centrifugally washing and drying the product to obtain the ZnO.
3. The production method according to claim 1, wherein the reducing gas is a mixed hydrogen-nitrogen gas or a mixed hydrogen-argon gas, and the molar mass of the hydrogen gas is 9 to 11% of the total molar mass of the reducing gas.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103706349A (en) * | 2014-01-21 | 2014-04-09 | 中国计量学院 | Nano ZnO microsphere/graphene photocatalyst and preparation method thereof |
| CN104098088A (en) * | 2014-06-17 | 2014-10-15 | 华南理工大学 | Preparation method for nano-zinc oxide modified graphene hybrid material |
| CN104262700A (en) * | 2014-09-10 | 2015-01-07 | 中国化工集团曙光橡胶工业研究设计院有限公司 | Preparation method of silicon dioxide graft graphene oxide/rubber composite material |
-
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103706349A (en) * | 2014-01-21 | 2014-04-09 | 中国计量学院 | Nano ZnO microsphere/graphene photocatalyst and preparation method thereof |
| CN104098088A (en) * | 2014-06-17 | 2014-10-15 | 华南理工大学 | Preparation method for nano-zinc oxide modified graphene hybrid material |
| CN104262700A (en) * | 2014-09-10 | 2015-01-07 | 中国化工集团曙光橡胶工业研究设计院有限公司 | Preparation method of silicon dioxide graft graphene oxide/rubber composite material |
Non-Patent Citations (3)
| Title |
|---|
| Bo Weng et al..Toward the enhanced photoactivity and photostability of ZnO nanospheres via intimate surface coating with reduced graphene oxide.《Journal of Materials Chemistry A》.2014, * |
| Catalytically engineered reduced graphene oxide/ZnO hybrid nanocomposites for the adsorption,photoactivity and selective oil pick-up from aqueous media;K. B. Babitha et al.;《RSC Advances》;20150521;第50223-50233页 * |
| Toward the enhanced photoactivity and photostability of ZnO nanospheres via intimate surface coating with reduced graphene oxide;Bo Weng et al.;《Journal of Materials Chemistry A》;20140403;第9388页左栏第4部分结论和Scheme 1，Supporting Information，第9384页Fig 3，第9381-9382页第2.2.3节 * |
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