Ternary compound optical catalyst and preparation method therefor and application thereof

The invention provides a preparation method for a titanium dioxide@graphene-cadmium sulfide ternary compound optical catalyst. The preparation method comprises: synthesizing titanium dioxide@graphene-cadmium sulfide in situ by virtue of a hydrothermal method including firstly inducing graphene to wrap titanium dioxide microspheres; and meanwhile, loading cadmium sulfide quantum dots on graphene nanosheets to form a ternary compound structure. Titanium dioxide and graphene are together used as an electron acceptor and a transfer of cadmium sulfide, so that the electron-hole separation time of cadmium sulfide is prolonged, and the purpose of enhancing the optical catalytic performance of the material is achieved. The method provided by the invention is simple to operate, short in synthetic period and easy to control. No additional noble metals are added as a co-catalyst, and the hydrogen production rate of the material can reach 715 [mu]mol/g/h. The optical catalyst prepared by the method provided by the invention can be repeatedly used.