Catalytic Function of IrOx in the Two-Step Thermochemical CO₂-Splitting Reaction at High Temperatures

Splitting CO 2 into CO and O 2 via a two-step thermochemical cycle by utilizing concentrated solar energy is a promising option for CO 2 reduction. Herein, to enhance the solar to fuel energy conversion efficiency, IrO x as a catalyst is used to increase the fuel production rate of the LaFeO 3 -based two-step thermochemical CO 2 -splitting reaction. Compared with LaFeO 3, 0.6 atom % IrO x as a catalyst that loaded on LaFeO 3 can almost double the maximal CO release rate and increase the maximal O 2 evolution rate 0.5 times; when a small amount of IrO x (2.5 atom %) is doped into the structure of LaFeO 3 through a solution combustion method, the initial CO generation rate can be increased by 5-fold. This work demonstrates that the catalytic function is still necessary in the two-step thermochemical CO 2 -splitting reaction even at high temperatures.