Multicomponent TiO₂/Ag/Cu₇S₄@Se Heterostructures Constructed by an Interface Engineering Strategy for Promoting the Electrocatalytic Nitrogen Reduction Reaction Performance

The electrocatalytic nitrogen reduction reaction (ECNRR) is a sustainable and environmentally friendly method for NH₃ synthesis under environmental conditions relative to the Haber–Bosch process; however, its low selectivity (Faradaic efficiency (FE)) and low NH₃ yield impede the progress. Herein, benefiting from the application of the interface engineering strategy, a multicomponent TiO₂/Ag/Cu₇S₄@Se-CC heterogeneous electrocatalyst with a unique structure was successfully fabricated, generating a unique sandwich structure by using a Ag layer as an electric bridge intercalated between TiO₂ and Cu₇S₄, in which the optimized catalyst can accelerate the electron transfer efficiency. Moreover, through the electronic structure adjustment, an electron-deficient region was constructed, which can inhibit the H₂ adsorption but enhance the N₂ adsorption, thereby improving the selectivity and the catalytic activity. Significantly, the FE and NH₃ yield of TiO₂/Ag/Cu₇S₄@Se-CC reached 51.05 ± 0.16% and 39.16 ± 2.31 μg h^–1 cm^–2, in which the FE is among the highest non-precious metal-based NRR electrocatalysts in alkaline electrolytes reported. This study provides insight into the rational design and construction of NRR electrocatalysts for electrocatalytic applications.