Highly efficient photocatalytic overall water splitting on plasmonic Cu₆Sn₅/polyaniline nanocomposites

A plasmonic Cu₆Sn₅/polyaniline (Cu₆Sn₅/PANI) nanocomposite was synthesized by chemical reduction and hydrothermal methods. The best photocatalytic overall water splitting performance was achieved by the Cu₆Sn₅/PANI_3wt% composite, which contains 3 wt% PANI, which is approximately three times more than that of pure Cu₆Sn₅. Meanwhile, Cu₆Sn₅/PANI_3wt% exhibited excellent photocatalytic stability for water splitting during the stability investigation. The dramatic promotion of the photocatalytic activity performance can be ascribed to the cocatalyst PANI. The existence of PANI can remarkably promote the separation and transfer efficiency of the photoinduced electron-hole pairs, and therefore enhance the photocatalytic activity. Our results also verify that the photogenerated charge comes from plasmonic Cu₆Sn₅ with the surface plasmon resonance (SPR) effect, which is different from traditional semiconductor-based photocatalysts. This work sheds some light on plasmonic photocatalyst development and provides an alternative pathway for photocatalytic reactions.