Advances in spin regulation of M-N-C single-atom catalysts and their applications in electrocatalysis

Abstract

To enhance the efficiency of green energy harvesting and pollutant degradation, significant efforts are focused on identifying highly effective catalysts. Metal-nitrogen-carbon single-atom catalysts (M-N-C SACs) have emerged as pivotal in catalysis due to their unique geometric structures, electronic states, and catalytic capabilities. Notably, the incorporation of magnetic elements at the active centers of these single-atom catalysts has garnered attention for their role in efficient electrochemical conversions. The orientation of spin states critically influences the adsorption and formation of reactants and intermediates, making the precise control of spin alignment and magnetic moments essential for reducing energy barriers and overcoming spin-related limitations, thereby enhancing catalytic activity. Thus, understanding the catalytic role of spin and modulating spin density at M-N-C single-atom centers holds profound fundamental and technological significance. In this review, we elucidate the fundamental mechanisms governing spin states and its influence in electrocatalysis. We then discuss various strategies for adjusting the spin states of active centers in the M-N-C SACs and the associated characterization techniques. Finally, we outline challenges and future perspectives of spin regulation for high-performance catalysts. This review provides deep insights into the micro-mechanisms of catalytic phenomena and offers a roadmap for designing spin-regulated catalysts for advanced energy applications.