CN103480398A - Micronano-structured and graphene based composite visible light catalytic material and preparing method thereof - Google Patents

Abstract

The invention relates to the technical field of photocatalysis, in particular to a micro-nano structured graphene-based composite visible light catalytic material and a preparation method thereof. The steps are as follows: dissolve graphene oxide in water, and ultrasonically treat it to obtain a graphene oxide dispersion; ultrasonically disperse silver nitrate and zinc oxide in deionized water to obtain a mixed solution, and add it dropwise to graphene oxide to disperse under stirring conditions. solution to obtain a mixed precursor; slowly add the configured phosphate solution dropwise to the mixed precursor of graphene oxide, silver nitrate and zinc oxide and continue to stir, and transfer the gray-green product obtained by the reaction into a hydrothermal reaction In the kettle, hydrothermal reaction is carried out at a certain temperature, after being cooled to room temperature, centrifuged, washed with deionized water and absolute ethanol respectively, and vacuum-dried to obtain the composite material. The invention has the advantages of simple preparation process, sufficient required raw materials and superior product performance, and exhibits strong degradation activity to the organic dye rhodamine B under excitation of visible light.

Description

A kind of micro-nano structure graphene-based composite visible light catalytic material and preparation method thereof

technical field

    The invention relates to the technical field of photocatalysis, in particular to a graphene-based composite visible light catalytic material with a micro-nano structure and a preparation method thereof, specifically to a rapid preparation of graphene/silver phosphate/zinc oxide with a micro-nano structure by a hydrothermal method The invention discloses a method for compounding visible light catalytic materials, belonging to the fields of composite materials, photocatalytic technology and water pollution control.

Background technique

Zinc oxide is a semiconductor material with unique photoelectric properties. It has the advantages of high activity, no pollution, large reserves, and low price, making it widely concerned in the field of photocatalysis. However, due to the large band gap of zinc oxide (3.7 eV), only It can use about 4% of the entire visible spectrum to stimulate the generation of electron-hole pairs; and its energy band structure can easily recombine the generated carrier pairs, resulting in a further reduction in its photocatalytic efficiency. Among the many attempts to increase the range and prolong the lifetime of carriers, it is an effective method to combine narrow bandgap semiconductor materials with zinc oxide to form heterostructure semiconductor materials.

Silver phosphate is a narrow bandgap semiconductor material (2.4 eV), which has strong visible light response characteristics and efficient catalytic degradation performance of pollutants; at the same time, the energy band structure of silver phosphate and zinc oxide can be well matched, so the zinc oxide Nanoparticles are compounded on silver phosphate particles to form a semiconductor photocatalytic material with a heterojunction structure, which can not only broaden the visible light response range of zinc oxide, but also make the electrons in the conduction band of zinc oxide It can be quickly transferred to the conduction band of silver phosphate (conduction band: ZnO>Ag ₃ PO ₄ ), and the holes in silver phosphate are quickly transferred to the valence band of zinc oxide (valence band: Ag ₃ PO ₄ > ZnO), avoiding the photogenerated The rapid recombination of carriers also prevents the reduction reaction between electrons and silver ions in silver phosphate to decompose silver phosphate, which improves the catalytic efficiency of the photocatalyst and enhances the cycle stability of the material.

Graphene is a new material with a single-layer sheet structure composed of carbon atoms. The thickness of a single-layer carbon source not only makes it suitable for the growth of functional nanomaterials, but also has good electronic conductivity. It has been recognized as a catalyst. As an ideal carrier material, graphene oxide is used as a precursor material in the experiment, and the nucleation and growth of silver phosphate are controlled during the reaction process, so that the final zinc oxide/silver phosphate/graphene composite photocatalytic material has a uniform morphology and relatively The small size, high light transmittance and high specific surface area of graphene make the prepared composite photocatalytic material have good dispersibility and adsorption in solution; its high electrical conductivity further accelerates the separation of photogenerated electron pairs , prolong the life of the active components, and enhance the catalytic activity of the composite photocatalytic material. According to the data verification, using commercial zinc oxide, graphene oxide, silver nitrate and phosphate as raw materials, the hydrothermal method is used to rapidly synthesize micro-nano structure The graphene/zinc oxide/silver phosphate composite visible light catalytic material and its use in photocatalytic degradation of organic pollutants and purification of water resources have not been reported.

Contents of the invention

The object of the present invention is to provide a method for preparing a graphene/zinc oxide/silver phosphate composite visible photocatalytic material with a micro-nano structure with a controllable morphology, which is simple in process, environmentally friendly and low in cost. The composite photocatalytic material prepared has strong Visible light response characteristics and excellent photocatalytic degradation performance of pollutants.

The technical solution adopted to realize the present invention is: using graphene oxide as a precursor material, uniformly compound micron-structured rod-shaped zinc oxide and silver phosphate particles on nanoscale graphene sheets by hydrothermal method, and its specific preparation The method steps are as follows:

(1) Graphene oxide is dissolved in deionized water and ultrasonically dispersed to obtain a graphene oxide dispersion with a concentration of 0.02-0.2 wt%.

(2) Dissolve silver nitrate and zinc oxide in deionized water, and obtain a mixed precursor solution A of silver nitrate and zinc oxide after ultrasonic treatment. The concentration of silver nitrate in mixed precursor solution A is 0.09 mol/L, and the concentration of zinc oxide The concentration is 0.2-0.8 wt%; the mixed precursor solution A is added dropwise to the above graphene oxide dispersion under the condition of magnetic stirring, the volume ratio of the mixed precursor solution A to the graphene oxide dispersion is 1:1, mix The solution was continuously stirred at room temperature for 6-12h to obtain a mixed precursor solution B;

(3) Dissolve phosphate in deionized water to obtain a phosphate solution with a concentration of 0.15 mol/L;

(4) Slowly add the phosphate solution prepared in step (3) dropwise to the mixed precursor solution B prepared in step (2) under the condition of magnetic stirring, and the volume ratio of the phosphate solution to the mixed precursor solution B is 1 : 5, until gray-green turbidity occurs in the reaction system, the mixed solution continues to stir for 30-60min and then transferred to a polytetrafluoroethylene inner container, and the inner container is sealed in a stainless steel hydrothermal reaction kettle, under the condition of 160-200°C React for 20-30 h. After the reaction, the reaction kettle is naturally cooled to room temperature. After centrifugation, the obtained product is washed with deionized water and absolute ethanol, and then vacuum-dried.

Phosphate described in step 3 is disodium hydrogen phosphate, sodium dihydrogen phosphate or sodium phosphate.

The mixed solution in step 2 is continuously stirred at room temperature for 6-12 hours, which means continuing to stir at a speed of 100 rpm for 6-12 hours.

In step 4, continue to stir the mixed solution for 30min-60min, then transfer it to the middle finger of the polytetrafluoroethylene liner and continue stirring at a speed of 200 rpm for 30min-60min.

Compared with the prior art, the present invention has the following advantages:

a) Zinc oxide and silver phosphate have a matching energy band structure, and they combine to form a heterojunction semiconductor material, which can promote the separation of electron-hole pairs generated by excitation, and can also improve the cycle stability of the material.

b) The prepared photocatalytic material has a wider visible light response range and light energy utilization rate.

c) Using graphene oxide as a precursor, the active attachment points on the surface of graphene oxide can effectively control the particle size and distribution of zinc oxide and silver phosphate particles on the graphene substrate.

d) The large specific surface area and high conductivity of graphene make the composite photocatalytic material have good dispersion, adsorption and low recombination of electron-hole pairs, so that the material has efficient catalytic oxidation ability under the action of visible light.

e) The preparation process is simple, the cost is low, energy saving and environmental protection, and the performance of the material is superior.

Description of drawings

Figure 1 is a scanning electron microscope image of a graphene-based composite visible light catalytic material with a micro-nano structure;

Fig. 2 is the X-ray diffraction pattern of micro-nano structured graphene-based composite visible light catalytic material;

Fig. 3 is the ultraviolet-visible diffuse reflectance spectrogram of micro-nano structured graphene-based composite visible photocatalytic material;

Fig. 4 is a graph showing the photocatalytic degradation curve of rhodamine B by the graphene-based composite visible light catalytic material with micro-nano structure under visible light.

Detailed ways

The content of the present invention will be further clarified below in conjunction with specific examples, but these examples do not limit the protection scope of the present invention.

Example 1

Disperse 10 mg of graphene oxide in 50 ml of deionized water and sonicate for 5 hours to obtain a graphene oxide dispersion, weigh 1.529 g of silver nitrate and 200 mg of ZnO and dissolve them in 50 ml of deionized water for 30 minutes to obtain a mixed precursor solution A, Add the mixed precursor solution A dropwise to the above graphene oxide dispersion under magnetic stirring, and continue to stir at a speed of 100 rpm at room temperature for 6 hours to obtain the mixed precursor solution B; weigh 0.426 g Na ₂ HPO ₄ Dissolve in 20 ml of deionized water to obtain a disodium hydrogen phosphate solution. Add the prepared disodium hydrogen phosphate solution dropwise to the mixed precursor solution B under agitation until gray-green turbidity appears in the reaction system, and the addition is completed The final mixed solution was transferred to a polytetrafluoroethylene liner after continuing to stir at a speed of 200 rpm for 30 minutes, and the liner was sealed in a stainless steel hydrothermal reactor, and reacted for 30 h at 160 ° C. After the reaction, The reaction kettle was naturally cooled to room temperature, and the obtained product was centrifuged and washed with deionized water and absolute ethanol respectively, and then vacuum-dried.

Example 2

Disperse 20 mg of graphene oxide in 50 ml of deionized water and sonicate for 5 hours to obtain a graphene oxide dispersion, weigh 1.529 g of silver nitrate and 300 mg of ZnO and dissolve them in 50 ml of deionized water for 30 minutes to obtain a mixed precursor solution A, Add the mixed precursor solution A dropwise to the above graphene oxide dispersion under magnetic stirring, and continue to stir at a speed of 100 rpm at room temperature for 8 hours to obtain the mixed precursor solution B; weigh 0.426 g Na ₂ HPO ₄ Dissolve in 20 ml of deionized water to obtain a disodium hydrogen phosphate solution. Add the prepared disodium hydrogen phosphate solution dropwise to the mixed precursor solution B under agitation until gray-green turbidity appears in the reaction system, and the addition is completed After the mixed solution was continued to stir at a speed of 200 rpm for 40 minutes, it was transferred to a polytetrafluoroethylene inner container, and the inner container was sealed in a stainless steel hydrothermal reactor, and reacted for 24 h at 180 ° C. After the reaction was completed, The reaction kettle was naturally cooled to room temperature, and the obtained product was centrifuged and washed with deionized water and absolute ethanol respectively, and then vacuum-dried.

Example 3

Disperse 50 mg of graphene oxide in 50 ml of deionized water and sonicate for 5 hours to obtain a graphene oxide dispersion, weigh 1.529 g of silver nitrate and 400 mg of ZnO and dissolve them in 50 ml of deionized water for 30 minutes to obtain a mixed precursor solution A, Add the mixed precursor solution A dropwise to the above graphene oxide dispersion under magnetic stirring, and continue to stir at a speed of 100 rpm at room temperature for 10 hours to obtain the mixed precursor solution B; weigh 0.426 g Na ₂ HPO ₄ Dissolve in 20 ml of deionized water to obtain a disodium hydrogen phosphate solution. Add the prepared disodium hydrogen phosphate solution dropwise to the mixed precursor solution B under agitation until gray-green turbidity appears in the reaction system, and the addition is completed The final mixed solution was transferred to a polytetrafluoroethylene liner after continuing to stir at a speed of 200 rpm for 50 minutes, and the liner was sealed in a stainless steel hydrothermal reactor, and reacted for 20 h at 200 ° C. After the reaction was completed, The reaction kettle was naturally cooled to room temperature, and the obtained product was centrifuged and washed with deionized water and absolute ethanol respectively, and then vacuum-dried.

Example 4

Disperse 100 mg of graphene oxide in 50 ml of deionized water and sonicate for 5 hours to obtain a graphene oxide dispersion, weigh 1.529 g of silver nitrate and 800 mg of ZnO and dissolve them in 50 ml of deionized water for 30 minutes to obtain a mixed precursor solution A, Add the mixed precursor solution A dropwise to the above graphene oxide dispersion under magnetic stirring, and continue to stir at a speed of 100 rpm at room temperature for 12 hours to obtain the mixed precursor solution B; weigh 0.426 g Na ₂ HPO ₄ Dissolve in 20 ml of deionized water to obtain a disodium hydrogen phosphate solution. Add the prepared disodium hydrogen phosphate solution dropwise to the mixed precursor solution B under agitation until gray-green turbidity appears in the reaction system, and the addition is completed The final mixed solution was transferred to a polytetrafluoroethylene liner after continuing to stir at a speed of 200 rpm for 60 minutes, and the liner was sealed in a stainless steel hydrothermal reactor, and reacted for 20 h at 200 ° C. After the reaction was completed, The reaction kettle was naturally cooled to room temperature, and the obtained product was centrifuged and washed with deionized water and absolute ethanol respectively, and then vacuum-dried.

Example 5

Disperse 10 mg of graphene oxide in 50 ml of deionized water and sonicate for 5 hours to obtain a graphene oxide dispersion, weigh 1.529 g of silver nitrate and 200 mg of ZnO and dissolve them in 50 ml of deionized water for 30 minutes to obtain a mixed precursor solution A, Add the mixed precursor solution A dropwise to the above graphene oxide dispersion under magnetic stirring, and continue stirring at a speed of 100 rpm at room temperature for 6 hours to obtain the mixed precursor solution B; weigh 0.36 g NaH ₂ PO ₄ Dissolve in 20 ml deionized water to obtain a sodium dihydrogen phosphate solution. Add the prepared sodium dihydrogen phosphate solution dropwise to the mixed precursor solution B under stirring until the reaction system appears gray-green turbid, and the addition is complete After the mixed solution was continued to stir at a speed of 200 rpm for 30 minutes, it was transferred to a polytetrafluoroethylene liner, and the liner was sealed in a stainless steel hydrothermal reactor, and reacted for 30 h at 160°C. The reaction kettle was naturally cooled to room temperature, and the obtained product was centrifuged and washed with deionized water and absolute ethanol respectively, and then vacuum-dried.

Example 6

Disperse 20 mg of graphene oxide in 50 ml of deionized water and sonicate for 5 hours to obtain a graphene oxide dispersion, weigh 1.529 g of silver nitrate and 300 mg of ZnO and dissolve them in 50 ml of deionized water for 30 minutes to obtain a mixed precursor solution A, Add the mixed precursor solution A dropwise to the above graphene oxide dispersion under magnetic stirring, and continue to stir at a speed of 100 rpm at room temperature for 8 hours to obtain the mixed precursor solution B; weigh 0.36 g NaH ₂ PO ₄ Dissolve in 20 ml deionized water to obtain a sodium dihydrogen phosphate solution. Add the prepared sodium dihydrogen phosphate solution dropwise to the mixed precursor solution B under stirring until the reaction system appears gray-green turbid, and the addition is complete The final mixed solution was transferred to a polytetrafluoroethylene liner after continuing to stir at a speed of 200 rpm for 40 minutes, and the liner was sealed in a stainless steel hydrothermal reactor, and reacted for 24 h at 180 ° C. After the reaction, The reaction kettle was naturally cooled to room temperature, and the obtained product was centrifuged and washed with deionized water and absolute ethanol respectively, and then vacuum-dried.

Example 7

Disperse 50 mg of graphene oxide in 50 ml of deionized water and sonicate for 5 hours to obtain a graphene oxide dispersion, weigh 1.529 g of silver nitrate and 400 mg of ZnO and dissolve them in 50 ml of deionized water for 30 minutes to obtain a mixed precursor solution A, Add the mixed precursor solution A dropwise to the above graphene oxide dispersion under magnetic stirring, and continue to stir at a speed of 100 rpm at room temperature for 10 hours to obtain the mixed precursor solution B; weigh 0.36 g NaH ₂ PO ₄ Dissolve in 20 ml deionized water to obtain a sodium dihydrogen phosphate solution. Add the prepared sodium dihydrogen phosphate solution dropwise to the mixed precursor solution B under stirring until the reaction system appears gray-green turbid, and the addition is complete The final mixed solution was transferred to a polytetrafluoroethylene liner after continuing to stir at a speed of 200 rpm for 50 minutes, and the liner was sealed in a stainless steel hydrothermal reactor, and reacted for 20 h at 200 ° C. After the reaction was completed, The reactor was naturally cooled to room temperature, and the obtained product was centrifuged, washed with deionized water and absolute ethanol, and dried in vacuum.

Example 8

Disperse 100 mg of graphene oxide in 50 ml of deionized water and sonicate for 5 hours to obtain a graphene oxide dispersion, weigh 1.529 g of silver nitrate and 800 mg of ZnO and dissolve them in 50 ml of deionized water for 30 minutes to obtain a mixed precursor solution A, Add the mixed precursor solution A dropwise to the above graphene oxide dispersion under magnetic stirring, and continue to stir at a speed of 100 rpm at room temperature for 12 hours to obtain the mixed precursor solution B; weigh 0.36 g NaH ₂ PO ₄ Dissolve in 20 ml deionized water to obtain a sodium dihydrogen phosphate solution. Add the prepared sodium dihydrogen phosphate solution dropwise to the mixed precursor solution B under stirring until the reaction system appears gray-green turbid, and the addition is complete The final mixed solution was transferred to a polytetrafluoroethylene liner after continuing to stir at a speed of 200 rpm for 60 minutes, and the liner was sealed in a stainless steel hydrothermal reactor, and reacted for 20 h at 200°C. The reaction kettle was naturally cooled to room temperature, and the obtained product was centrifuged and washed with deionized water and absolute ethanol respectively, and then vacuum-dried.

Example 9

Disperse 10 mg of graphene oxide in 50 ml of deionized water and sonicate for 5 hours to obtain a graphene oxide dispersion. Weigh 1.529 g of silver nitrate and 200 mg of ZnO, dissolve them in 50 ml of deionized water and sonicate for 30 minutes to obtain a mixed precursor solution A, and add the mixed precursor solution A dropwise to the above graphene oxide dispersion under magnetic stirring, Continue stirring at a speed of 100 rpm at room temperature for 6 hours to obtain a mixed precursor solution B; weigh 0.49 g Na ₃ PO ₄ and dissolve it in 20 ml deionized water to obtain a sodium phosphate solution. The solution was added dropwise to the mixed precursor solution B until gray-green turbidity appeared in the reaction system. After the dropwise addition, the mixed solution continued to stir at a speed of 200 rpm for 30 minutes and then transferred to a polytetrafluoroethylene liner. The liner was sealed in a stainless steel hydrothermal reactor, and reacted at 160 °C for 30 h. After the reaction, the reactor was naturally cooled to room temperature. After the obtained product was centrifuged, it was washed with deionized water and absolute ethanol, and then vacuum-dried. .

Example 10

Disperse 20 mg of graphene oxide in 50 ml of deionized water and sonicate for 5 hours to obtain a graphene oxide dispersion. Weigh 1.529 g of silver nitrate and 300 mg of ZnO, dissolve them in 50 ml of deionized water and sonicate for 30 minutes to obtain a mixed precursor solution A, and add the mixed precursor solution A dropwise to the above graphene oxide dispersion under magnetic stirring, Continue stirring at a speed of 100 rpm at room temperature for 8 hours to obtain a mixed precursor solution B; weigh 0.49 g Na ₃ PO ₄ and dissolve it in 20 ml deionized water to obtain a sodium phosphate solution. The solution was added dropwise to the mixed precursor solution B until gray-green turbidity appeared in the reaction system. After the dropwise addition, the mixed solution continued to stir at a speed of 200 rpm for 40 minutes and then transferred to a polytetrafluoroethylene liner. The liner was sealed in a stainless steel hydrothermal reactor, and reacted at 180 °C for 24 hours. After the reaction, the reactor was naturally cooled to room temperature. After centrifugation, the obtained product was washed with deionized water and absolute ethanol, and then vacuum-dried. .

Example 11

Disperse 50 mg of graphene oxide in 50 ml of deionized water and sonicate for 5 hours to obtain a graphene oxide dispersion. Weigh 1.529 g of silver nitrate and 400 mg of ZnO, dissolve them in 50 ml of deionized water and ultrasonicate for 30 minutes to obtain a mixed precursor solution A, and add the mixed precursor solution A dropwise to the above graphene oxide dispersion under magnetic stirring, Continue stirring at a speed of 100 rpm at room temperature for 10 hours to obtain a mixed precursor solution B; weigh 0.49 g Na ₃ PO ₄ and dissolve it in 20 ml deionized water to obtain a sodium phosphate solution. The solution was added dropwise to the mixed precursor solution B until gray-green turbidity appeared in the reaction system. After the dropwise addition, the mixed solution continued to stir at a speed of 200 rpm for 50 minutes and then transferred to a polytetrafluoroethylene liner. The liner was sealed in a stainless steel hydrothermal reactor, and reacted for 20 h at 200 °C. After the reaction, the reactor was naturally cooled to room temperature. After the obtained product was centrifuged, it was washed with deionized water and absolute ethanol, and then vacuum-dried. .

Example 12

Disperse 100 mg of graphene oxide in 50 ml of deionized water and sonicate for 5 hours to obtain a graphene oxide dispersion. Weigh 1.529 g of silver nitrate and 800 mg of ZnO, dissolve them in 50 ml of deionized water and sonicate for 30 minutes to obtain a mixed precursor solution A, and add the mixed precursor solution A dropwise to the above graphene oxide dispersion under magnetic stirring, Continue stirring at a speed of 100 rpm at room temperature for 10 hours to obtain a mixed precursor solution B; weigh 0.49 g Na ₃ PO ₄ and dissolve it in 20 ml deionized water to obtain a sodium phosphate solution. The solution was added dropwise to the mixed precursor solution B until gray-green turbidity appeared in the reaction system. After the dropwise addition, the mixed solution continued to stir at a speed of 200 rpm for 60 minutes and then transferred to a polytetrafluoroethylene liner. The liner was sealed in a stainless steel hydrothermal reactor, and reacted at 200 °C for 20 h. After the reaction, the reactor was naturally cooled to room temperature. After the obtained product was centrifuged, it was washed with deionized water and absolute ethanol, and then vacuum-dried. .

Figure 1 is the scanning electron microscope image of the prepared micro-nano structured graphene-based composite visible photocatalytic material. From the figure, we can see that the fine Ag ₃ PO ₄ particles gather around the zinc oxide rods, and the flake shape can also be seen in the figure. Graphene sheet; Figure 2 is the X-ray diffraction pattern of the prepared micro-nanostructure graphene-based composite visible light catalytic material, and all the diffraction peaks in the diffraction pattern correspond to the silver phosphate and zinc oxide of the response well, because The amount of graphene oxide added to the reactant is small, so the content of graphene obtained after reduction is also low. In addition, the diffraction peak intensity of graphene is relatively weak compared to the crystallized silver phosphate and zinc oxide diffraction peaks, so in X-ray No diffraction peaks derived from graphene can be observed in the diffraction pattern; Figure 3 is the UV-visible diffuse reflectance spectrum of the prepared micro-nano structured graphene-based composite visible photocatalytic material, from which we can see that the composite The material has good absorption in the whole ultraviolet-visible region (200-800 nm), and the absorbance exceeds 0.8.

Ultrasonic dispersion of 50 mg of micro-nano-structured graphene-based composite visible light catalytic material in 100 ml of 25 mg/L rhodamine B solution was followed by ultrasonication for 10 minutes, and the evenly mixed dispersion was transferred to a quartz bottle in a xenon light catalytic reactor After stirring for 30 minutes in the dark to reach adsorption equilibrium, turn on the xenon lamp light source, use a syringe to extract 4 mL of the irradiated mixed dispersion every 10 minutes and transfer it to a marked centrifuge tube, turn off the xenon lamp light source after 1 hour of visible light irradiation, All the samples in the centrifuge tubes were centrifuged, and the supernatant obtained after centrifugation was further transferred to a quartz cuvette, and the absorbance at different photocatalytic times was measured on a UV-visible spectrophotometer, so as to obtain the Photocatalytic degradation curve of rhodamine B by micro-nano structured graphene-based composite visible light catalytic materials under visible light irradiation.

Fig. 4 is the photocatalytic degradation curve of rhodamine B under the visible light condition (200-800 nm) of the micro-nano structured graphene-based composite visible photocatalytic material prepared in Example 1, as can be seen from Fig. 4, the The degradation rate of rhodamine B of the composite material is close to 80% after 30 minutes of visible light irradiation, and 100% after 40 minutes of visible light irradiation. The photocatalytic degradation curve shows that the graphene/silver phosphate/zinc oxide composite with micro-nano structure The photocatalytic material has an efficient photocatalytic degradation effect on the organic dye Rhodamine B under visible light irradiation. the

Claims (5)

1. the graphene-based composite visible light catalysis material of micro-nano structure, it is characterized in that: described composite visible light catalysis material is formed by zinc oxide, silver orthophosphate and three kinds of Material claddings of Graphene; This composite visible light catalysis material all has absorption preferably in the ultraviolet-visible district of 200-800 nm, absorbance surpasses 0.8; Described composite visible light catalysis material has efficient photocatalytic degradation effect to the organic dyestuff rhodamine B under the UV, visible light optical excitation of 200-800 nm: the 30 minutes degradation rates of rhodamine B solution to 25 mg/L reach 100% over 80%, 40 minute degradation rate.

2. the preparation method of the graphene-based composite visible light catalysis material of a kind of micro-nano structure as claimed in claim 1, is characterized in that comprising the steps:

(1) graphene oxide is dissolved in to deionized water for ultrasonic and disperses, the graphene oxide dispersion liquid that to obtain concentration be 0.02-0.2 wt%;

(2) silver nitrate and zinc oxide are dissolved in deionized water, obtain the mixing precursor solution A of silver nitrate and zinc oxide after ultrasonic processing, the concentration of mixing silver nitrate in precursor solution A is 0.09 mol/L, and the oxidation zinc concentration is 0.2-0.8 wt%; To mix precursor solution A is added drop-wise in above-mentioned graphene oxide dispersion liquid under the magnetic agitation condition, the volume ratio of mixing precursor solution A and graphene oxide dispersion liquid is 1:1, mixed solution at room temperature continues to stir 6-12h, obtains mixing precursor solution B;

(3) phosphate is dissolved in deionized water, obtains the phosphate solution that concentration is 0.15 mol/L;

(4) in the mixing precursor solution B that the phosphate solution prepared by step (3) under the condition of magnetic agitation dropwise slowly adds step (2) to prepare, phosphate solution is 1:5 with the volume ratio of mixing precursor solution B, until occur the celadon muddiness in reaction system, mixed solution is transferred in polytetrafluoroethylliner liner after continuing to stir 30-60min, and inner bag is sealed in the stainless steel hydrothermal reaction kettle, reaction 20-30 h under 160-200 ° of C condition, after reaction finishes, reactor naturally cools to room temperature, wash respectively the final vacuum drying with deionized water and absolute ethyl alcohol after resulting product centrifugation.

3. the preparation method of the graphene-based composite visible light catalysis material of a kind of micro-nano structure as claimed in claim 1, is characterized in that described mixed solution in step (2) at room temperature continues to stir 6-12h and refers to that the speed with 100 rev/mins continues to stir 6-12h.

4. the preparation method of the graphene-based composite visible light catalysis material of a kind of micro-nano structure as claimed in claim 1, is characterized in that the phosphate described in step (3) is sodium hydrogen phosphate, sodium dihydrogen phosphate or sodium phosphate.

5. the preparation method of the graphene-based composite visible light catalysis material of a kind of micro-nano structure as claimed in claim 1, is characterized in that transferring to the polytetrafluoroethylliner liner middle finger after mixed solution continuation stirring 30min-60min in step (4) stirs 30min-60min with the speed continuation of 200 rev/mins.

Images