Synthesis and VOC degradation ability of a CeO 2 /WO 3 thin-layer visible-light photocatalyst

Abstract The plasma synthesis, characterization, and photocatalytic activity of WO 3 , which consisted of a mixture of gamma WO 3 and epsilon WO 3 (γ/e-WO 3 ), and physically mixed WO 3 and CeO 2 (WO 3 /CeO 2 ) were investigated. Synergistic effects were observed in acetaldehyde photocatalysis experiments using γ/e-WO 3 or WO 3 /CeO 2 . The synergistic effect in the γ/e-WO 3 photocatalyst system is proposed to be the concurrent reduction of oxygen at gamma WO 3 and oxidation of acetaldehyde at epsilon WO 3 . It is hypothesized that acetaldehyde preferentially interacts with epsilon WO 3 over gamma WO 3 because of dipole–dipole interactions between them. In the case of the WO 3 /CeO 2 photocatalyst, the electron scavenging property of CeO 2 aided charge carrier separation. As a result, WO 3 /CeO 2 exhibited excellent photocatalytic activity in volatile organic compound decomposition under visible light at room temperature.