Copper ferrite and cobalt oxide two-layer coated macroporous SiC substrate for efficient CO₂-splitting and...

CO₂-splitting and thermochemical energy conversion effectiveness are still challenged by the selectivity of metal/metal oxide-based redox materials and associated chemical reaction constraints. This study proposed an interface/substrate engineering approach for improving CO₂-splitting and thermochemical energy conversion through CuFe₂O₄ and Co₃O₄ two-layer coating SiC. The newly prepared material reactive surface area available for gas-solid reactions is characterized by micro-pores CuFe₂O₄ alloy easing inter-layer oxygen micro mass exchanges across a highly stable SiC-Co₃O₄ layer. Through a thermogravimetry analysis, oxidation of the thermally activated oxygen carriers exhibited remarkably CO₂-splitting capacities with a total CO yield of 1919.33 µmol/g at 1300 °C. The further analysis of the material CO₂-splitting performance at the reactor scale resulted in 919.04 mL (788.94 µmol/g) of CO yield with an instantaneous CO production rate of 22.52 mL/min and chemical energy density of 223.37 kJ/kg at 1000 °C isothermal redox cycles. The reaction kinetic behavior indicated activation energy of 30.65 kJ/mol, which suggested faster CO₂ activation and oxidation kinetic on SiC-Co₃O₄-CuFe₂O₄ O-deficit surfaces. The underlying mechanism for the remarkable thermochemical performances was analyzed by combining experiment and density functional theory (DFT) calculations. The significance of exploiting the synergy between CuFe₂O₄ and Co₃O₄ layers and stoichiometric reaction characteristics provided fundamental insights useful for the theoretical modeling and practical application of the solar thermochemical process.