Electrocatalytic performance of Sb-modified Bi₂₅FeO₄₀ for nitrogen fixation

The Haber-Bosch N₂ fixation method suffers from the power-consuming and harsh conditions. In contrast, the electrochemical conversion of N₂ (NRR) at room temperature and atmospheric pressure is considered a promising alternative route. In this study, we synthesized Sb-modified with Bi₂₅FeO₄₀ (BFSO/BFO) by using one-step hydrothermal treatment. The BFSO/BFO catalyst has higher selectivity to NRR than Bi₂₅FeO₄₀ (BFO) under the same applied voltage. Such large interfacial interaction area plays a critical role in transfer electron and enhances the density of current. The resulting BFSO/BFO heterojunction showed significant electrocatalytic activity under controllable voltage, which exhibited favorable average ammonia (NH₃) yield as high as 2.62 μg·h^-1·cm^-2 at -0.2 V versus RHE. Moreover, the stability of the BFSO/BFO composite was evaluated for six cycles and the results were desirable. This study provides a new insight into the design of composite catalysts using BFO, which has high activity and selectivity toward NRR.