Recent developments of single atom alloy catalysts for electrocatalytic hydrogenation reactions

Abstract

This review discusses the recent developments of single-atom alloy (SAA) catalysts toward CO2, CO, N2, and NO3– hydrogenation reactions in the electrocatalysis context, a natural expansion from the thermal catalysis origin where the concept of SAA was born and validated. Electrocatalytic hydrogenations of CO2, CO, NO3–, and N2 into value-added chemicals offer an attractive general route to mitigate greenhouse gas emissions using renewable energy without H2 feed stream. These reactions typically involve multiple electron-transfer-coupled elementary reaction steps that are of broad relevance to many electrocatalytic applications, making them well-positioned for translational fundamental studies relevant to other emerging electrochemical reactions. While there has been exciting progress in SAA research for various thermal catalytic reactions in the last decade, the design, application, and characterization of SAA catalysts in electrocatalysis remain nascent with intriguing uncertainties and ample opportunities. We highlight the recent research findings in this growing area, where the SAAs, owing to their unique doped metal properties and atomically precise bimetallic synergies, promote selective reaction pathways by tuning binding energies and distributions of adsorbates/intermediates. We also provide our perspective on this growing research area's potential challenges and opportunities.