W-N3 center supported on blue phosphorus as a promising efficient electrocatalyst with ultra-low limiting potential for nitrogen fixation

Highlights: • The W-N₃@β-P has excellent electrocatalytic activity to reduce N₂ into NH₃. • The center peak of hybridization energy level between the W atom and N atom of absorbed N₂ was located in Fermi level. • W-N₃ catalytic center acts as electron acceptor, while β-P as electron reservoir. • NRR proceeds with an ultra-low limiting potential (−0.02 V) by distal mechanism. The nitrogen reduction reaction (NRR) becomes increasingly important while it is challenging processes in electrochemistry for the challenge to find the high-efficiency and high-selectivity catalysts. Herein, we systematically screened the capacity of a sequence of representative transition metal-N₃ (TM-N₃) centers supported on blue phosphorus (TM-N₃@β-P) as NRR catalysts by using of density functional theory (DFT). Our results show that W-N₃ center supported on blue phosphorus (W-N₃@β-P) exhibits an excellent catalytic performance with an ultra-low limiting potential of −0.02 V, while the competitive hydrogen evolution reaction (HER) can be suppressed on this catalyst. This work thus predicts W-N₃@β-P has potential applications for electrocatalytic NRR.