Nonequilibrium CO₂ utilisation via vibrational activation in plasma catalysis

With the rapid expansion of renewable electricity, CO₂ conversion into fuels and chemicals is attracting growing interest as a route toward circular carbon utilisation. However, the high chemical stability of CO₂ makes its efficient activation a central challenge. Molecular vibrational excitation can couple with reaction coordinates, thereby reducing the translational energy required to access transition-state regions and enhancing reactivity. Nonthermal plasma can generate vibrationally excited CO₂ under nonequilibrium conditions, offering a practical route to exploit vibrational activation in catalytic reactions. This Feature Article reviews how vibrational energy promotes CO₂ activation and examines the generation and relaxation of vibrationally excited CO₂ in plasma, together with its relevance to catalytic surface reactions. Particular emphasis has been placed on our mechanistic studies of plasma-catalytic CO₂ conversion, in which vibrationally excited CO₂ is proposed to couple with surface reaction coordinates and facilitate elementary steps that are difficult to achieve thermally. These findings provide a basis for designing plasma-catalytic systems through molecular-level control of energy distribution and surface reactivity.