The facile synthesis of and light-driven water splitting on a hetero-metallic bismuth oxide catalyst

The process of water photo-electrolysis possesses the capability to generate sustainable and renewable hydrogen fuels, consequently addressing the challenge of the irregularity of solar energy. Thus, developing highly-efficient and low-cost electrocatalysts for the use in contemporary renewable energy devices is critical. Herein, we report the fabrication of a novel BaCeFe_x−yBi_xO₆ nanocrystalline material through a one-step solvothermal route using a post-annealing process at 500 °C. The synthesized material was investigated for its light-induced electrochemical HER and OER activities in alkaline media and the results revealed that the as-prepared BaCeFe_x−yBi_xO₆-500 °C exhibited an excellent OER activity with an overpotential of 100 mV to achieve a current density of 10 mA cm⁻², thus outperforming the IrO₂ electrocatalyst. Besides its excellent water oxidation performance, the catalyst also demonstrated an admirable HER activity comparable to that of the Pt/C catalyst, indicating that the higher temperature treatment plays a significant role in achieving the maximum performance of the developed electrocatalyst. This work provides insights into the enhancement of light-induced OER and HER activities of bismuth oxides for a wide range of catalytic applications.