Recent progress in nickel single-atom catalysts for the electroreduction of CO₂ to CO

The electrocatalytic reduction of carbon dioxide (CO₂) is considered an effective strategy for mitigating the energy crisis and the greenhouse effect. Nickel is widely used in single-atom catalysts (SACs) owing to its special electronic structure. In this minireview, the basic principles of Ni SACs in the electrocatalytic reduction of CO₂ to CO are first described. Subsequently, Ni SACs are divided into three categories depending on different strategies used to improve properties. The synthesis, morphology, performance and theoretical calculations of the catalysts are also described. Finally, an overview of the existing challenges and perspectives of Ni SACs for CO₂ reduction is presented.