TiO[sub 2]-Phosphotungstic Acid Photocatalysis Systems with an Energy Storage Ability

Abstract

Phosphotungstic acid (PWA) was utilized as the reductive energy storage substance instead of conventional for the fabrication of an energy storage photocatalyst, which retains its reducing ability even after light irradiation. In the case where a PWA film was electrochemically charged at −0.8 V vs. Ag/AgCl for 1 h in 3 wt% aqueous NaCl, it showed longer self-discharge time than a film of the same thickness. Photoelectrochemical properties of the PWA and films coated with porous were also studied. The PWA and films could be charged under UV light for 1 h in 3 wt% aqueous NaCl. Although the amount of charge accumulated in the film was smaller than that in the film, the self-discharge time of the former was longer. Slower self-discharging process by which may be advantageous for some applications, of the former is responsible for these results. The film showed relatively good durability after several cycles. © 2003 The Electrochemical Society. All rights reserved.