CO₂ reutilization processes contribute to the mitigation of CO₂ as a potent greenhouse gas (GHG) through reusing and converting it into economically valuable chemical products including methanol, dimethyl ether, and methane. Solar thermochemical conversion and photochemical and electrochemical CO₂ reduction processes are emerging technologies in which solar energy is utilized to provide the energy required for the endothermic dissociation of CO₂. Owing to the surface-dependent nature of these technologies, their performance is significantly reliant on the solid reactant/catalyst accessible surface area. Solid porous structures either entirely made from the catalyst or used as a support for coating the catalyst/solid reactants can increase the number of active reaction sites and, thus, the kinetics of CO₂ reutilization reactions. This paper reviews the principles and application of porous materials for CO₂ reutilization pathways in solar thermochemical, photochemical, and electrochemical reduction technologies. Then, the state of the development of each technology is critically reviewed and evaluated with the focus on the use of porous materials. Finally, the research needs and challenges are presented to further advance the implementation of porous materials in the CO₂ reutilization processes and the commercialization of the aforementioned technologies.

A representative volume of LCMA coated porous SiC showing a maximum of 23% shrinkage when subject to high-temperature CO ₂ conversion redox reactions. This results in significant structural changes including a reduction in specific surface area.