Structural and Electronic Modulations of Se-Vacancy-Rich MoSe Triggered by Cr Doping toward Robust Nitrogen Reduction Reaction.

The electrocatalytic nitrogen reduction reaction (NRR) is proposed as an alternative to the Haber-Bosch process, but the development of efficient NRR electrocatalysts remains a challenging task. MoSe has superior conductivity compared to MoS, making it promising in the NRR field. Unfortunately, the scarcity of active sites and competitive hydrogen evolution reaction (HER) hinder its broader applications. Here, Se-vacancy-rich MoSe is designed through Cr doping, allowing for targeted regulations of architectural and electronic structure by leveraging the dual effects of doping and V. Further mechanistic studies innovatively find that the Cr-induced multi-vacancy (18.75% concentration) exerts inverse contributions to NRR on 2H- and 1T-MoSe, reflecting boosted and depressed effects, respectively. Consequently, suitable doping effectively facilitates NRR and eases the competition from HER, realizing excellent NH yield (51.53 ± 2.45 µg h mg ) and Faradaic efficiency (63.37%) in MSC-1. This work paves the opportunity for MoSe-based electrocatalysts toward boosted NRR.