Fabrication and enhanced hydrogen evolution reaction performance of a Cu3BiS3 nanorods/TiO2 heterojunction film.

Highly active and durable hydrogen evolution reaction (HER) catalysts are required for the low-cost and high-yield generation of clean energy from water splitting. Herein, a Cu3BiS3/TiO2 (C@T) heterojunction film is constructed by a facile dip-coating method for the synthesis of Cu3BiS3 nanorods on a TiO2 film. The heterojunction film is used as a catalyst in water splitting which exhibits a higher photoelectrochemical (PEC) performance and electrocatalytic activity than the respective pure Cu3BiS3 nanorods counterpart. Experimental results confirm that the PEC performance of the C@T heterojunction film displays a strong photoresponse of as high as ∼1.5 × 10−4 A cm−2 at an applied potential of −0.5 V vs. Ag/AgCl under visible light irradiation. What's more, the as-prepared C@T film shows the best electrocatalytic performance with an onset overpotential of 150 mV, a low Tafel slope of 42.67 mV dec−1, a large current density of 10.8 mA cm−2 at an overpotential of 220 mV, and a remarkable cycling stability. The enhanced PEC performance is associated with the formation of a heterojunction structure at the interface between TiO2 and Cu3BiS3, which facilitates light absorption and separation of photogenerated charge carriers. The growth of Cu3BiS3 nanorods on a TiO2 film modified the electronic structure and increased the electrochemical area, and thus is responsible for enhanced catalytic activity. Benefitting from its scalable preparation and properties, the Cu3BiS3 nanorods/TiO2 heterojunction film is indeed a promising catalyst for hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]