A new heterogeneous photocatalyst based on Wells–Dawson polyoxometalate and nickel coordination compounds: synthesis, structure and property

Abstract

Polyoxometalate (POM) as a promising photocatalyst has gained much attention for the removal of organic pollutants from water. However, the two main drawbacks of low visible-light photocatalytic activity due to wide oxygen-to-metal charge transfer band of POM and high solubility in solution make them difficult to recover and recycle impeding potential applications. We have prepared a new heterogeneous POM photocatalyst, namely [Ni(2,2′-bpy)₃]₃[P₂W₁₈O₆₂] (2,2′-bpy = 2,2′-bipyridine, NiPW), characterized by X-ray single crystal diffraction, elemental analyses, FTIR, XRPD, and UV-DRS. The photocatalyst NiPW exhibits two broad band centered at 513 nm and 770 nm, extending induced light to visible region. As a photocatalyst, NiPW composite not only shows excellent visible light photocatalytic activity for the photodegradation of methyl orange in the presence of H₂O₂, but also can be easily separated by simple centrifugation for its insoluble property and recycled.