Rational design of carbon-supported single and dual atom catalysts for bifunctional oxygen electrocatalysis

Design and engineering of effective bifunctional electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) represents a critical first step in the further development of rechargeable metal-air batteries, a sustainable energy technology. Recently, nanocomposites based on metal species atomically dispersed within carbon scaffolds have emerged as viable alternatives to the conventional precious metal-based electrocatalysts. In this review, we summarize the latest progress by including a brief introduction to the fundamentals of ORR/OER electrochemistry and an overview of the synthetic strategies and bifunctional performances of carbon-based nanocomposite catalysts with single and dual metal sites. We conclude the review with a perspective about the challenges and opportunities for further innovation of carbon-supported nanocomposites for bifunctional oxygen electrocatalysis.