High temperature induced S vacancies in natural molybdenite for robust electrocatalytic nitrogen reduction

Defect engineering is an important strategy to regulate electronic structure of electrocatalysts for electrochemical N-2 fixation, aiming at improving the electron state density and enhancing the adsorption and activation of inert N-2. In this paper, a high-temperature strategy to anneal the natural molybdenite under Ar atmosphere was developed, and the as-obtained molybdenite with S vacancies boosted a high activity for N-2 reduction reaction. In 0.1 M HCl, the catalyst annealed at 800 degrees C exhibits a high Faradic efficiency of 17.9% and a NH3 yield of 23.38 mu g h(-1) mg(cat)(-1). at -0.35 V versus reversible hydrogen electrode, two times higher than that of the pristine molybdenite. The facile one-step annealing method introduces the defects (e.g., S vacancies) in the surface of the natural molybdenite particles to prepare catalysts for generating ammonia by reducing nitrogen at room temperature under ordinary pressure, promoting the development of low-carbon economic prospect. (C) 2021 Elsevier Inc. All rights reserved.

Automated summary

Defect engineering is a crucial strategy to enhance the electronic structure of electrocatalysts for N-2 fixation, aiming at improving the electron state density and promoting the adsorption and activation of inert N-2. The high-temperature annealing method under Ar atmosphere introduces defects (e.g., S vacancies) in the surface of natural molybdenite particles, boosting the catalytic activity for N-2 reduction reaction. The catalyst annealed at 800 degrees C exhibits a high Faradic efficiency and NH3 yield in 0.1 M HCl, showing promising potential for generating ammonia at room temperature under ordinary pressure.