Visible‐Light Photochromism of Polyoxometallate H₄PMo₁₁VO₄₀ Composite Film Based on Polyvinylpyrrolidone with a Fast Response

The visible‐light photochromic composite films with a fast response were prepared by entrapping H 4 PMo 11 VO 40 into polyvinylpyrrolidone (PVP) networks. PMo 11 V/PVP composite films’ structure and morphology were characterized by IR spectroscopy, XRD and TEM. The skeleton structure of PMo 11 V and PVP were still remained through IR spectroscopy analysis. The photochromism performance of PMo 11 V/PVP composite films were analyzed by UV‐vis absorption. The photochromic process showed a first‐order kinetics. Meanwhile, the mechanism of photochromism composite films was investigated by XPS. PMo 11 V/PVP composite films with excellent circulation ability of rising‐fading color which has good application potential.