Enhanced photochromism of heteropolyacid/polyvinylpyrolidone composite film by TiO2 doping

• Published in: Journal of applied polymer science Vol. 132; no. 10
• Main Authors: Lu, Cong, Sun, Yan, Liu, Jialu, Wang, Xiansheng, Liu, Su-Ling, Feng, Wei
• Format: Journal Article
• Language: English
• Published: Hoboken Blackwell Publishing Ltd 10.03.2015; Wiley Subscription Services, Inc
• Subjects: Materials science; photochromic performance; Polymers; polyoxometalates; polyvinylpyrrolidone; TiO2 doping
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.41583

ABSTRACT Novel composite film was synthesized by TiO2 doping into phosphomolybdic acid (PMoA)/polyvinylpyrrolidone (PVP) system. The influence of TiO2 doping on its microstructure and photochromic properties was investigated via atomic force microscopy, transmission electron microscope, Fourier transform infrared spectroscopy (FT‐IR), ultraviolet–visible spectra, and X‐ray photoelectron spectroscopy (XPS). After TiO2 doping, the surface of TiO2/PMoA/PVP composite film changed to rough from smooth, and the particle size significantly increased. The FT‐IR results verified that the basic structure of PMoA and PVP were not destroyed in the composite films. The non‐bonded interaction between the acid and polymer was strengthened by TiO2 doping. Irradiated with UV light, composite films changed from colorless to blue. The TiO2/PMoA/PVP composite film exhibited a strong photochromic effect and faster bleaching reaction than that of PMoA/PVP film. XPS results indicated that the amount of PMoA in photo‐reductive reaction was increased after TiO2 doping, which resulted in the photochromic efficiencies enhanced. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41583.