Fabrication of WO 3-based composite films and improvement its photochromic properties by copper doping

Abstract

Tungsten-based photochromic composite films were fabricated using peroxopolytungstic acid methanol solution and transparent urethane resin. The composite films showed photochromic properties by UV-vis light irradiation. Photochromic properties of the films were improved with addition of the other elements of Cu. The reaction rate constants k of the films with the Cu/W ratio of 0, 0.1, 0.5, and 1 were 2.68 × 10 -2, 3.33 × 10 -2, 2.57 × 10 -2, and 1.51 × 10 -2 min -1, and the constant of the film with Cu/W of 0.1 was larger than that of the nondoped film. © 2012 The Chemical Society of Japan.