Applied Chemical Engineering

Polyoxometalate (POM) is an eco-friendly solid acid. It is a polyatomic anion containing transition metal (group Ⅴ or group Ⅵ) oxyanions, which are connected by common oxygen atoms. In addition to the advantages of other photocatalysts, such as non-toxic, no secondary pollution, convenient, fast and efficient, it also has the characteristics of high oxygen rich surface, and because there are a large number of metal centers in its structure, it can show rapid reversible and multi electron redox transformation. Its band gap is narrow, and the spectral response range is wide. It has excellent photocatalytic degradation performance, and has been widely used in photocatalytic degradation of wastewater containing organic pollutants. In this paper, the types of polyoxometalates photocatalysts, the modification methods of polyoxometalates and the application of polyoxometalates and its compounds in the degradation of organic pollutants are reviewed. The prominent problems and corresponding solutions of polyoxometalates photocatalytic degradation technology at present are pointed out, and its future development direction is prospected.

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