Recent advances of single-atom catalysts in CO2 conversion

The catalytic transformation of CO2 into valuable fuels/chemicals is a promising and economically profitable process because it offers an alternative toward fossil feedstocks and the benefit of transforming and cycling the CO2 on a scale-up. Cost-effective and high efficiency catalysts are of extremely significance to cut down the utilizing costs of CO2. Numerous studies have been carried out to develop the catalyst design for the conversion processes. Traditional metal nanoparticle-based catalysts still need to promote the active metal utilization efficiency, catalytic activity, and selectivity. Inspirationally, single-atom catalysis (SACs) has aroused significant interest of researchers owing to their maximum atom utilization, unique electronic structure, and strong metal–support interaction, offering promising strategies to facilitate the catalytic efficiency and long-term stability. The well-designed and specific structure of SACs also affords the merits to essential studies for revealing the underlying mechanism and active sites during the CO2 utilization. In this review, we summarize and emphasize the recent progress in the development of advanced SACs for electrocatalytic, photocatalytic, and thermocatalytic conversion of CO2 into versatile products (CO, CH4, CH3OH, HCOOH, and C2+ products). In addition, the general principles of SAC design and the structure–performance relationship that were also systematically and constructively investigated serve as a way to explore the key parameters in deciding the catalytic performance. Moreover, we display the catalytic efficiency of different SACs for CO2 conversion published recently to offer an in-depth assessment of these catalysts. Finally, the main challenges and perspectives in the future applications of SACs toward CO2 conversion are also considered.