Rh-loaded High-entropy Oxide for Efficiently Catalyzing the Reverse Water-Gas Shift Reaction

Establishing efficient CO₂ hydrogenation technology based on the reverse water-gas shift (RWGS) reaction can effectively alleviate environmental problems while providing high-value-added products. The development of suitable advanced supports is the key to improving the catalytic activity and selectivity. Herein, we designed and synthesized a new type of spinel-phase high entropy oxides [(FeCrMnAlGa)₃O_4-x, FMG], which exhibited remarkable RWGS performance after loading small-size Rh nanoparticles. The CO yield was as high as 145.5 μmol_CO·g_cat⁻¹· at 380 °C and the CO selectivity was nearly 100%. Moreover, the catalyst retained over 95% of the initial activity after 25 h of continuous catalyzing. Experimental and structural studies reveal that the FMG support has elemental synergy and high-entropy stability, which affect the Rh dispersion and oxygen vacancy generation, in turn achieving superior catalytic performance.