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 CO 2 emissions to chemical feedstocks using renewable H 2 . However, achieving high selectivity and activity at low temperatures remains challenging due to the thermodynamically more favorable CO 2 methanation reaction. Here we develop a robust Ru 0.0025 Ce 0.7 Fe 0.3 O 2−δ solid-solution nanorod catalyst featuring a ternary Fe–Ru–oxygen vacancy (V O ) center, overcoming limitations in intermediate adsorption and dissociation on single-component catalysts. Incorporating a trace amount of Ru (0.25 at. %) into Ce 0.7 Fe 0.3 O 2−δ markedly enhances CO 2 and H 2 dissociation and H 2 O formation, while the primary Ce 0.7 Fe 0.3 O 2−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 Ru 0.0025 Ce 0.7 Fe 0.3 O 2−δ, yielding a CO production rate of 326 mmol g cat –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.