CO₂ photoreduction to CO/CH₄ over Bi₂W_0.5Mo_0.5O₆ solid solution nanotubes under visible light

Abstract

In this work, Bi₂W_0.5Mo_0.5O₆ solid solution nanotubes have been synthesized through a structure-directing hard template approach, which demonstrated greatly enhanced CO₂ photoreduction to CO/CH₄. The crystalline phase, components and morphologies of the as-prepared composites were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The present design of Bi₂W_0.5Mo_0.5O₆ solid solution nanotubes leads to remarkably enhanced photocatalytic activities with a peak CO/CH₄ production rate of 6.55/3.75 mmol g^-1 h^-1 under visible light irradiation at room temperature, which was about 7 times that on pure Bi₂WO₆ and Bi₂MoO₆ nanotubes, respectively. Hollow nanotubular structures and synergistic electronic effects of various elements contribute to the enhanced visible light photocatalytic activity of Bi₂W_0.5Mo_0.5O₆ solid solution nanotubes.