Electrocatalytic reduction of nitrogen to ammonia on metal nanoclusters: insights and trends from d- and p-block metals

Abstract

The electrocatalytic reduction of nitrogen (NRR) to ammonia on metal nanoclusters represents a transformative approach to sustainable ammonia synthesis, offering a greener alternative to the highly energy-intensive Haber–Bosch process, which is a significant contributor to global CO₂ emissions. By harnessing renewable electricity under ambient conditions, electrocatalytic NRR could dramatically lower the carbon footprint and enable decentralized, on-demand ammonia production. However, the inherent stability of N₂ presents a major obstacle to its efficient activation. Metal nanoclusters, with their distinctive electronic and structural characteristics, have emerged as highly promising catalysts to overcome this challenge. This study systematically investigates the NRR catalytic performance of a broad spectrum of d-block and p-block metal nanoclusters. Through the use of Genetic Algorithms (GA) for global minimum structure optimization and comprehensive mechanistic pathway analysis, we uncover key trends in N₂ activation, NRR reaction pathways, selectivity, and efficiency across various nanoclusters. Our findings provide critical insights into the design of advanced NRR electrocatalysts, paving the way for more sustainable and efficient technologies for ammonia production.