Enhanced electrocatalytic nitrogen reduction reaction performance by interfacial engineering of MOF-based sulfides FeNi2S4/NiS hetero-interface

A series of FeNi 2 S 4 /NiS hetero-interface electrocatalysts with unique electronic structures are successfully constructed by interfacial engineering. Particularly, the optimized FeNi 2 S 4 (311)/NiS (101) electrocatalyst is obtained by modulating the different exposed crystal planes, which shows superior nitrogen reduction performance with high NH 3 yield and high Faradaic efficiency. • MOF-based sulfides FeNi 2 S 4 /NiS hetero-interface electrocatalysts are firstly constructed. • FeNi 2 S 4 (311)/NiS(101) shows superior electrocatalytic NRR performance. • The unique surface electronic structure of catalysts is the intrinsic reason for the excellent NRR performance. • DFT calculations further reveal the changes the d-band center and the rate-degerming step. Electrocatalytic Nitrogen Reduction Reaction (ECNRR) is a promising alternative NH 3 production method relative to Haber-Bosch process. However, the ECNRR still suffers from rather low NH 3 yield and selectivity (Faradaic efficiency (FE)) due to the poor catalytic activity of catalysts. Herein, benefiting from interface engineering, FeNi 2 S 4 /NiS hetero-interface electrocatalysts with unique electronic structures are successfully constructed, which the optimized catalyst can enhance the adsorption of N 2 molecules meanwhile inhibit H atoms adsorption. Significantly, the NH 3 yield and FE of FNS/CC-2 are reached to 128.398±1.32 μg h −1 cm −2 and 28.64 ± 0.18% which are higher than most of non-noble metal-based NRR electrocatalysts in alkaline electrolyte reported. Detailed experimental investigation and DFT calculations reveal that the enhanced electrocatalytic performance and selectivity of FeNi 2 S 4 /NiS towards N 2 are attributed to the changes of the D-band center and electronic structure of electrocatalyst surface. The construction strategy of this NRR electrocatalyst provides a new avenue on electrocatalytic research.