Low bias photoelectrocatalytic (PEC) performance for organic vapour degradation using TiO2/WO3 nanocomposite

In this study, a novel photoelectrocatalytic (PEC) flat-plate type device used in the gas-phase was fabricated by the technology of screen printing. The TiO2/WO3 nanocomposite (2:8 in mole ratio) was prepared by a simple milling-anneal method and printed onto the device. The obtained device was attempted to investigate the PEC performance by applying low biases for degrading the volatile organic compounds (VOCs). The apparent pseudo-first-order kinetic model was used to describe the degradation process. The results showed that the applied low bias had a distinct enhancement effect on the degradation activity compared to photocatalytic (PC) degradation. The PEC degradation rate under UV-light (365 nm) irradiation by applying only 0.2 V bias was about 12.28 x 10(-3) min(-1), which was 2.42 times of PC degradation rate. Under the blue-light (475 nm) irradiation, the composite still had good degradation efficiency and the rate constant was about 2.6 x 10(-3) min(-1). Furthermore, the explanation was proposed that the degradation activity of TiO2/WO3 composite could show obviously enhancement for gas-phase PEC process by applying bias at a very low level, compared to pure TiO2. (C) 2010 Elsevier B.V. All rights reserved.