Sulfur-deficient Bi2S3−x synergistically coupling Ti3C2Tx-MXene for boosting electrocatalytic N2 reduction

Electrocatalytic nitrogen reduction reaction (NRR) is an appealing route for the sustainable NH 3 synthesis, while developing efficient and durable NRR catalysts remains at the heart of achieving high-efficiency N 2 -to-NH 3 electrocatalysis. Herein, we rationally combine vacancy and interface engineering to design sulfur-deficient Bi 2 S 3 nanoparticles decorated Ti 3 C 2 T x -MXene as an effective NRR catalyst. The developed Bi 2 S 3 nanoparticles decorated Ti 3 C 2 T x -MXene (Bi 2 S 3− x /Ti 3 C 2 T x ) naturally contained abundant S-vacancies and exhibited a dramatically boosted NRR activity with an NH 3 yield of 68.3 µg·h −1 mg −1 (−0.6 V) and a Faradaic efficiency of 22.5% (−0.4 V), far superior to pure Bi 2 S 3 and Ti 3 C 2 T x , and surpassing almost all ever reported Bi- and MXene-based NRR catalysts. Theoretical investigations unveiled that the exceptional NRR activity of Bi 2 S 3− x /Ti 3 C 2 T x stemmed from its dual-active-center system involving both S-vacancies and interfacial-Bi sites, which could synergistically promote N 2 adsorption and *N 2 H formation to result in an energetic-favorable NRR process.