Two‐dimensional Sn 2 Ta 2 O 7 nanosheets as efficient visible light‐driven photocatalysts for hydrogen evolution

Two‐dimensional Sn 2 Ta 2 O 7 nanosheets with a thickness of ~ 10 nm were successfully prepared through a novel tantalic acid‐based solid‐state reaction method at reduced temperature. The as‐obtained samples were characterized by powder X‐ray diffraction (XRD), ultraviolet–visible (UV–Vis) diffuse reflectance spectra, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Brunauer–Emmett–Teller (BET) analysis. The photocatalytic performance of Sn 2 Ta 2 O 7 nanosheets was evaluated by photocatalytic water splitting for hydrogen evolution under visible light irradiation ( λ ≥ 400 nm). The Sn 2 Ta 2 O 7 nanosheets with a large surface area of 25.9 m 2 ·g −1 showed higher H 2 production activity, which was about 4.4 times higher than that of bulk Sn 2 Ta 2 O 7 in lactic acid aqueous solutions using Pt as a co‐catalyst. The improved photocatalytic performance mainly benefited from the nanosheet structure, which provided abundant surface active sites and facilitated the photogenerated charge carrier separation efficiently. This work may open up new opportunity to develop novel nanostructured tantalum‐based semiconductors with improved catalytic performance for solar energy conversion.