Cu sulfides as a template for Ag/Cu sulfide catalysts for electrochemical CO ₂ . With the introduction of Ag, nanosheet show increased C2+ product generation. The catalysts undergo a morphology evolution as CO ₂ reduction proceeds.

Single‐atom catalysts (SACs) based on transition metals represent a promising strategy for maximizing the utilization efficiency of metal atoms and engineering specific active sites for energy‐related applications, especially for catalysis. However, there remain many unresolved challenges such as maintaining single‐atom stability at high loadings and understanding how supports affect local electronic environments during catalysis. This review focuses on transition metal dichalcogenides (TMDs) as supports that anchor single metal atoms via defect and phase engineering while demonstrating high catalytic activity. The mechanisms of single‐atom immobilization on TMD surfaces were first elaborated, followed by discussing the corresponding synthetic strategies for achieving precise control. Using examples primarily from hydrogen evolution reaction, oxygen evolution reaction, nitrogen reduction reaction, and oxygen reduction reaction, this work outlines the major design strategies, synthesis, characterizations, catalytic applications, and remaining challenges. This review aims to advance the development of highly efficient, stable, and scalable TMD‐based SACs for sustainable energy conversion applications.