Urchin-like Bi 2 S 3 modified TiO 2 for improved photocathodic protection of 304SS

Severe charge recombination and poor light absorbance are the limiting factors for TiO 2 to access efficient photocathodic protection (PCP) towards metals. Engineering the TiO 2 with Bi 2 S 3 to form the heterojunction is proposed to overcome these limitations. Impressively, the optimal Bi 2 S 3-12 h@TiO 2 photoanode coupled with 304SS displays an open circuit potential that negatively shifts to-480 mV vs Ag/AgCl, accompanied by a photoinduced current of 18.5 mu A/cm 2 . Comprehensively, characterizations discover that a tight interface between TiO 2 and Bi 2 S 3 exhibits strong electron interaction. The resulting enhanced PCP performance is attributed to extending the photoresponse range, increasing the carrier density, and improving the photocarrier separation. This work proves and validates the effectiveness of Bi 2 S 3 @TiO 2 in enhancing the PCP performance and provides the instruction to construct a high-performance photoanode.