Metal Single‐Atom Electrocatalysts Excel from Coordination Configuration via Heteroatoms Tuning

ABSTRACT Supported atomically dispersed metal catalysts (ADMCs) have received enormous attention due to their high atom utilization efficiency, mass activity and excellent selectivity. Single‐atom catalysts (SACs), characterized by a monometal center, have been extensively studied in catalysis‐related fields. It should be emphasized that the catalytically active state is not a zero‐valent isolated metal atom, but a charged metal center stabilized by coordination. In fact, these metal atoms are coordinated with the atoms from the support, involving electron transfer and typically exhibiting a nonzero charge. The synergistic interaction between the metal atom and its surrounding coordination atoms is the primary driver of high catalytic activity. Optimizing the coordination environment of the single‐atom active sites is essential for enhancing the physical and chemical properties of the catalysts, thereby achieving high electrocatalytic activity, selectivity, and stability. Rationally designing and engineering the coordination environment of single metal MNx sites and their local structures is crucial for enhancing intrinsic activity. Heteroatom doping not only provides stable coordination sites of metal atoms but also modulates their electronic structure through the strategic selection of heteroatoms with varying atomic radii and electronegativities. This review aims to provide a comprehensive summary of the recent development of such single‐atom electrocatalysts regulated by heteroatoms for various energy‐conversion reactions. Meanwhile, the challenges and perspectives in the emerging field of heteroatom‐doped single‐atom electrocatalysis are also discussed.