Unveiling the synergistic effect between the metallic phase and bridging S species over MoS2 for highly efficient nitrogen fixation

Abstract

Electrocatalytic nitrogen reduction reaction (NRR) is considered an appealing approach towards sustainable NH₃ production but still undergoes serious challenges with unsatisfactory catalytic performance, which hinders its large-scale application. In this work, the S-rich 1T‐MoS₂ with an ultrahigh 1T phase content and S-enrichment has been successfully synthesized and firstly verified as an exceptional NRR catalyst with high activity and selectivity. The optimized MoS_2.30 catalyst exhibits a high NH₃ yield rate (98.30±1.63 μg h^–1 mg^–1_cat.) and FE (23.10±0.38%), surpassing nearly all the reported MoS₂-based NRR catalysts and the overwhelming majority of advanced NRR catalysts, demonstrating the encouraging role-playing of the synergistic effect between 1T phase and bridging S₂^2– species on NRR performances. DFT calculations reveal that the high properties empowered by MoS_2.30 are on account of the synergistic effect that induces the enhanced NRR activity via the strengthened N₂ adsorption and reduced energy barrier (E_b) as well as the improved NRR selectivity through the optimized competitive adsorption and reduced energy barrier against the hydrogen evolution reaction (HER). This work fabricates a MoS₂-based electrocatalyst for highly efficient NRR and proves an effective strategy to improve the catalytic performance, which is worth being extended to other catalytic reactions.