Accelerating Photocatalytic Activity by Tailoring Cocatalysts on Polycrystalline Tungsten(VI) Oxide Microplates

In this study, the structure-activity relationship of the WO3 photocatalyst and the role of cocatalysts deposited on the WO3 surface were analyzed. Investigation of the phase transformation of WO3 microplates revealed that amorphous WO3 was progressively crystallized into monoclinic WO3 during consecutive thermal treatments. The obtained WO3 microplates were used for the photocatalytic decomposition of organic dyes under simulated solar light irradiation to understand the effect of the crystal structure on the photocatalytic activity. The crystal phase of the WO3 microplates with a monoclinic structure was optimal for the photocatalytic reaction. However, the effects of the crystal phase and the surface area of the WO3 sample were very small, and a deposited metal cocatalyst was essential for achieving photocatalytic activity. The detailed mechanisms and influence of cocatalysts on the WO3 surface were discussed.