Nickel and Frustrated Lewis Pairs on Ceria as Dual-Active Sites for Enhanced CO2 Reduction at Low Temperatures

The simultaneous and efficient activation of CO₂ and H₂ is critical for enabling rapid CO₂ methanation at low temperatures, which is essential for practical integration with intermittent renewable H₂ sources and significant process energy savings. In this study, we have successfully developed an innovative dual-active site catalyst that consists of Ni nanoparticles and surface-anchored heterologous frustrated Lewis pairs (FLPs) supported on CeO₂–Ov. This catalyst exhibits a remarkable enhancement in the efficiency of low-temperature CO₂ methanation. The FLP-rich Ni/CeO₂–Ov catalyst demonstrates exceptional performance at 350 °C, achieving 91.3% CO₂ conversion and ∼99% CH₄ selectivity. These results not only approach thermodynamic equilibrium limits but also far exceed those of conventional Ni/CeO₂ catalysts. Combined experimental and computational analyses reveal that the superior catalytic activity arises from the FLP structure, where adjacent Ce³⁺···O^2– and OH groups synergistically activate and convert the slurry to CO₂. Moreover, compared to Ni/CeO₂, the Ni nanoparticles in Ni/CeO₂–Ov exhibit enhanced H₂ activation and dissociation, along with a significantly lower energy barrier for hydrogen spillover to CeO₂. The synergistic interaction between FLP sites and Ni active centers dramatically boosts the reaction kinetics. This work provides novel insights into the rational design of highly efficient multisite CO₂ methanation catalysts.