Abstract

Green and economical CO₂ utilization is significant for CO₂ emission reduction and energy development. Here, the 1D Mo₂C nanowires with dominant (101) crystal surfaces were modified by the deposition of atomic functional components Rh and K. While unmodified β­Mo2C could only convert CO₂ to methanol, the designed catalyst of K₀.₂Rh₀.₂/β-Mo₂C exhibited up to 72.1% of ethanol selectivity at 150 °C. It was observed that the atomically dispersed Rh could form the bifunctional active centres with the active carrier β­Mo2C with the synergistic effects to achieve highly specific controlled C–C coupling.

By promoting the CO₂ adsorption and activation, the introduction of an alkali metal (K) mainly regulated the balanced performance of the two active centres, which in turn improved the hydrogenation selectivity. Overall, the controlled modification of β­Mo₂C provides a new design strategy for the highly efficient, low-temperature hydrogenation of CO₂ to ethanol with single-atom catalysts, which provides an excellent example for the rational design of the complex catalysts.

Graphical abstract

Controlled C–C coupling to ethanol: The single-atom catalyst (SAC) with synergistic bifunctional effects has been developed to achieve the controlled C–C coupling to ethanol from CO₂ hydrogenation. A third component (K) was effectively incorporated to regulate the balanced kinetics of the two functions, thus, giving superior ethanol selectivity at the mild conditions.