Two-dimensional transition metal dichalcogenides for electrocatalytic nitrogen fixation to ammonia: Advances, challenges and perspectives. A mini review

Abstract

Ammonia (NH3), a significant source of hydrogen and one of the principal constituents of fertilizer, has always been a compound of great interest and importance. However, the standard Haber–Bosch process for the synthesis of ammonia requires high temperature and high pressure, so researchers have recently focused on producing ammonia from nitrogen via a green and pollution-free method by employing the electrocatalytic nitrogen reduction reaction (NRR) under mild conditions. However, compared with industrial-scale nitrogen fixation, the yield of electrocatalytically produced ammonia is currently too low, so new catalysts with better performance are sought. Two-dimensional transition metal dichalcogenides (TMDCs) are promising catalysts for nitrogen reduction, owing to their unique electronic structure, large specific surface area, and low cost. In this paper, the NRR mechanisms are discussed and recent progress in using TMDCs in artificial nitrogen fixation is critically reviewed. We also consider strategies that could improve the performance of TMDCs for nitrogen fixation, with an emphasis on interface engineering and defect engineering. Finally, the existing limitations are discussed and the prospects for obtaining catalysts with better selectivity and higher catalytic performance are considered.

Keywords

• Two-dimensional transition metal dichalcogenides
• Electrocatalytic nitrogen fixation
• Electrochemistry