Synthesis of Nanovoid Bi2WO6 2D Ordered Arrays as Photoanodes for Photoelectrochemical Water Splitting

Abstract

Herein we report a facile and economic method to prepare nanovoid Bi₂WO₆ 2D ordered arrays employing a simple self-assembly procedure. The electrochemical properties and performance of the 2D nanoarray as a photoanode for water splitting are investigated and compared with a conventional photoanode of similar thickness. The 2D array photoanode shows a much higher photocurrent density and photon-to-H₂ conversion efficiency even with a small content of the Bi₂WO₆ material. The enhancement is further studied and explained on the basis of the superiority of light scattering and photogenerated hole diffusion within the 2D array structure. This work provides a facile method to improve the efficiency of solar energy conversion systems by minimizing the charge-carrier diffusion length and reducing the light reflection, as well as reducing the amount of the semiconductor material (often costly and/or rare) present in the photoanode.