Tungsten Oxide Composite Photocatalyst

Compared with the common tungsten oxide photocatalyst, the tungsten oxide composite photocatalyst has more excellent material activity on the photocatalytic performance. The photocatalytic activity of tungsten oxide composite photocatalyst mainly depends on its photocatalytic current-carrying particle separation process.

To improve the photogenerated electron-hole separation, is a way to fundamentally improve the photocatalytic activity of tungsten oxide photocatalysts. For most semiconductor photocatalysts, there is an unavoidable high photoionization electron-hole recombination rate. The compounding of one kind of semiconductor with another kind of semiconductor whose energy band is matched can remarkably improve the separation efficiency of photogenerated carriers. Tungsten oxide composite photocatalyst photo-generated carrier separation process there are many, but in general can be attributed to the two main forms. One is for photo-generated carriers to migrate between two semiconductors.

In this way, according to the two different semiconductor energy band structure can be divided into several different migration path. In general, however, there is a common characteristic: the photogenerated electrons with higher reduction ability can migrate to another semiconductor with weaker reducing ability under the action of the electric field gradient generated at different energy bands. Photogenerated holes also migrate from valence bands of semiconductors with higher oxidation capabilities to semiconductors with weaker oxidation capabilities. Without impairing the redox reaction, the photocatalytic performance of the composite photocatalyst can be greatly enhanced by the effective photocarrier separation.

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