Nanocluster and single-atom catalysts for thermocatalytic conversion of CO and CO2

In this Minireview, we discuss recent advances in understanding nanocluster and single-atom catalysts for CO and CO2 emissions control applications. Through analyzing thermocatalytic CO oxidation and CO2 reduction, two fundamentally and industrially important reactions, we compare representative nanocluster and single-atom catalytic systems from perspectives of intrinsic chemistry and reaction engineering. Generally, nanoclusters and single atoms display different catalytic performances (i.e., activity, selectivity, and stability) for these reactions depending on the synthesis methods, support materials, and reaction conditions. Key observations of activity and selectivity tradeoffs between nanoclusters and single-atom catalysts are highlighted. The dynamic structural responses of these catalytic species under CO oxidation or CO2 reduction reaction conditions are also discussed. Synthetic control and detailed experimental and computational characterization of single-atom and nanocluster catalysts for CO and CO2 conversion have led to exciting progress over the past decade. Still, more efforts are needed to understand and develop catalysts that meet the environmental, energy, and technical requirements to power a sustainable global economy.