Advancements in Electrocatalytic Nitrogen Reduction Reaction: A Review on the Role of Catalyst Electronic Structure and Design Strategies

Ammonia, an essential chemical for fertilizer production and a promising energy carrier, is mainly produced through the traditional, energy-intensive Haber–Bosch process. Recently, there has been significant attention directed toward electrocatalytic nitrogen reduction reaction (NRR) for ammonia synthesis, attributed to its energy-saving and environmentally friendly characteristics. The research community has focused on designing environmentally friendly nanocatalysts for electrocatalytic NRR to achieve reduced energy consumption. To attain superior catalytic performance and selectivity, it is imperative to systematically design electrocatalysts that optimize processes such as mass transport, chemisorption, and physisorption, as well as proton- and electron-transfer mechanisms. Herein, building upon the mechanisms of the electrocatalytic NRR, we comprehensively outline catalysts from an electronic structure perspective to achieve highly selective electrocatalytic NRR. This review initially introduces the role of catalyst electronic structure in NRR and the mechanisms of electrocatalytic NRR. Subsequently, it summarizes and discusses recent advances in the rational design and development of electronic structures for electrocatalytic NRR, focusing on vacancies, alloys, and dopants. Finally, it addresses the challenges and future prospects of catalyst electronic structure design in electrocatalytic NRR research with the goal of developing more reliable and efficient NRR electrocatalysts.