Accelerating Reverse Water Gas Shift Reaction through Synergistic CO2 and H2 Activation on Ru–Fe–(VO-in-CeO2) Ternary Catalytic Centers

The reverse water gas shift (RWGS) reaction shows promise for converting CO2 emissions to chemical feedstocks using renewable H2. However, achieving high selectivity and activity at low temperatures remains challenging due to the thermodynamically more favorable CO2 methanation reaction. Here we develop a robust Ru0.0025Ce0.7Fe0.3O2−δ solid-solution nanorod catalyst featuring a ternary Fe–Ru–oxygen vacancy (VO) center, overcoming limitations in intermediate adsorption and dissociation on single-component catalysts. Incorporating a trace amount of Ru (0.25 at. %) into Ce0.7Fe0.3O2−δ markedly enhances CO2 and H2 dissociation and H2O formation, while the primary Ce0.7Fe0.3O2−δ solid-solution component facilitates CO desorption, lowering the RWGS onset temperature to ∼200 °C. Experimental and computational analyses verify improved kinetics and stable performance with Ru0.0025Ce0.7Fe0.3O2−δ, yielding a CO production rate of 326 mmol gcat–1 h–1, ∼100% selectivity, and a 21% yield, approaching the thermodynamic limit within a 5 min batch reaction at ∼450 °C surface temperature under 300 W xenon lamp illumination.