Controlling ordered lasso arrangement of Fe and Zn to construct FeS/ZnS/ZIF-8-L with rich heterogeneous interfaces for boosting electrochemical nitrogen fixation

Electrocatalytic nitrogen reduction reaction (ENRR) is considered as a potential pathway for green synthesis of ammonia. However, the kinetic barriers of ENRR remain a tough challenge, which is imperative to design high effective electrocatalysts for accelerated activation of N N. Herein, the FeS/ZnS/ZIF-8-L with rich heterogeneous interfaces was successfully fabricated by governing the ordered lasso arrangement of Fe and Zn nodes in Fe-2MIM/ZIF-8-L precursor, where Fe and Zn were separately fixed in the confined space of ZIF-8-L and Fe-2MIM. Such intertwined Fe-2MIM/ZIF-8-L structure was beneficial to control the location and concentration of FeS and ZnS after sulfidation pyrolysis. The high-efficiency FeS/ZnS/ZIF-8-L exposed more catalytic active sites and possessed optimal electronic structure resulting in the lowered energy barrier of ENRR and the enhanced adsorption and activation of N 2 , which confirmed by experimental and theoretical characterization results. As a result, FeS/ZnS/ZIF-8-L displayed an optimal NH 3 yield rate of 89.52 μg h −1 mg −1 and Faradaic efficiency of 16.78 %, which surpassed most reported heterostructured ENRR catalysts. Our findings shed a new insight to govern the interfaces density of heterostructured electrocatalysts by predesigning the location of two metals in precursor, which can motivate an in-depth exploration to advanced catalysts for various electrocatalytic reactions.