(Bi19S27I3)(0.6667) nanorods with more negative potentials of conduction band as highly active photocatalysts under visible light

The rational design of photocatalysts with more negative potentials of the conduction band is of vital importance in improving the performance of photocatalysts for reduction reactions. In this work, highly crystalline and uniform (Bi19S27I3)(0.6667) nanorods were firstly synthesized by a one-step hydrothermal process. The formation of the (Bi19S27I3)(0.6667) nanorods consists of nucleation and crystal growth in agglomerates of spherical particles. The obtained (Bi19S27I3)(0.6667) nanorods with a narrow band gap of about 1.80 eV, a wide visible light absorption spectrum, and a more negative conduction band potential are capable of producing high-reducibility electrons, and an efficiently photogenerated carriers separation capability. The results demonstrate that the (Bi19S27I3)(0.6667) nanorods can be as efficient and stable photocatalysts for Cr(VI) photoreduction and RhB degradation reactions. The photocatalytic reduction efficiency of Cr(VI) over the (Bi19S27I3)(0.6667) nanorods was determined to be more than 3 times those of the corresponding BiOI and Bi2S3 photocatalysts under visible light. The detailed formation mechanism of (Bi19S27I3)(0.6667) nanorods and the reaction mechanism of Cr(VI) photoreduction were proposed based on various characterizations.