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

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 1 T phase content and S-enrichment has been successfully synthesized and firstly verified as an exceptional NRR catalyst with high activity and selectivity. The optimized MoS2.30 catalyst exhibits a high NH3 yield rate (98.30 ± 1.63 μg h–1 mg–1cat.) 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 1 T phase and bridging S22– species on NRR performances. DFT calculations reveal that the high properties empowered by MoS2.30 are on account of the synergistic effect that induces the enhanced NRR activity via the strengthened N2 adsorption and reduced energy barrier (Eb) 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.