Activating VS2 basal planes for enhanced NRR electrocatalysis: the synergistic role of S-vacancies and B dopants

Abstract

The nitrogen reduction reaction (NRR) is a pivotal step in electrochemical N₂ fixation to NH₃. VS₂ holds great promise as a NRR electrocatalyst, but its high activity requires the sufficient activation of inert basal planes. Herein, we demonstrate the first successful activation of VS₂ basal planes toward the NRR by introducing S-vacancies (Vs) and B-dopants. The theoretical calculations unravel that the synergistic role of V_S and B-dopants enables the most effective activation of VS₂ basal planes by creating unique B-adjacent-unsaturated-V active sites that can significantly promote the NRR while suppressing hydrogen evolution. The synthesized B-doped VS₂ nanoflowers with enriched surface Vs delivered an NH₃ yield of 55.7 μg h⁻¹ mg⁻¹ (−0.4 V) and a faradaic efficiency (FE) of 16.4% (−0.2 V) and represent the best V-based catalysts to date. Our theoretical and experimental findings may facilitate the exploration and understanding of advanced transition-metal disulfide catalysts for the NRR.