A kind of graphene-coated zno photocatalyst and preparation method thereof

Abstract

The invention relates to a graphene cladded ZnO (Zinc Oxide) photocatalyst and a preparation method of the ZnO photocatalyst. The surface of ZnO is enabled to have electropositivity; afterwards, the ZnO is compounded with an oxygen-containing functional group with electronegativity on graphene oxide, so as to obtain a graphene oxide cladding ZnO photocatalyst. According to the graphene cladded ZnO compound photocatalyst prepared by the preparation method, as used graphene is relatively large in flake diameter and relatively small in layer quantity; the ZnO is mostly compounded with the graphene with planes; the stress between the graphene and the ZnO is decreased; the structure of the graphene can be greatly maintained not to be destroyed. Meanwhile, the ZnO is compounded with the graphene oxide through electrostatic force self-assembly, so that the graphene can be used for cladding the surface of the ZnO; thus, the contact area between the graphene and the ZnO is increased and the agglomeration of the graphene is reduced; the action between the graphene and the ZnO is enhanced; the separation and the transmission of a photon-generated carrier generated by a ZnO catalyst are more facilitated; the photocatalysis effect can be obviously improved by the structure.

Description

technical field [0001] 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 technique [0002] Organic dyes and wastewater pollutants are major sources of pollution in industries such as textiles, paper, and plastics. ZnO is an important photocatalyst with a wide band gap (3.37eV) and a large exciton binding energy (60meV), and has a strong sensitivity to light, which is beneficial to the photocatalytic degradation of organic matter in wastewater. . [0003] The excited electrons and holes generated by photoexcitation of ZnO are easily recombined and converted into light energy quickly, resulting in a decrease in catalytic performance. Therefore, researchers have adopted many methods to suppress the recombination of photogenerated electron-hole pairs and broaden the photoresponse area, such as controlling the morphology of ZnO, doping with other metal ion...

AI Technical Summary

Problems solved by technology

[0004] Although there are many reports on ZnO / graphene composite photocatalysts and their preparation methods, there are still many problems, such as the poor composite effect of ZnO and graphene, a lot of free graphene exists in the composite, and graphene agglomeration is serious. , the graphene structure is severely damaged, which is not conducive to the improvement of photocatalytic activity.

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