Heterojunction Interface Synergistically Enables Efficient Electrochemical Nitrogen Reduction for Ammonia Synthesis

ABSTRACT Highly efficient electrocatalytic nitrogen reduction for ammonia synthesis is considered one of the most promising green and sustainable approaches for ammonia synthesis at present. In this study, by effectively employing two strategies, namely the π – π electron channels of porous π – π stabilized supramolecular nanocage‐based π frameworks and heterojunction interface regulation, the issues of poor conductivity and low N ₂ selectivity of BiO _2‐X are addressed. The performance of composite catalysts obtained by adjusting the heterojunction interface between π‐2 and BiO _2‐X through doping Co with different molar ratios via the liquid‐phase reduction method was tested. Among them, for BiO _2‐X /π‐2 doped with 30% Co, the NH ₃ production rate and faradaic efficiency (FE) at a potential of −0.48 V (vs. RHE) were 30.9 µg·h ⁻¹ ·mg _cat ⁻¹ and 77.9%, respectively. Experiments show that adjusting the heterojunction interface between BiO _2‐X and π‐2 plays a role in improving electrocatalytic nitrogen reduction for ammonia synthesis. Doping Co can increase the oxygen vacancies in BiO _2‐X , activate and regulate the Bi 4p orbitals, and form a bimetal‐N bridge, which is beneficial for improving electrical conductivity.