A highly efficient solar-driven CO₂ reforming of methane on Ni/MgAlO_x-LDH loaded Ni foam reactors with heat recovery: Experimental measurements and numerical simulations

By converting two greenhouse gases into fuels, CO₂ reforming of CH₄ via free and clean solar energy is a promising solution to the energy shortage and global warming problems simultaneously. However, serious challenges such as limited light-to-fuel efficiency, severe catalyst aggregation, and deactivation still exist for reactors employing traditional catalyst powders. Here, Ni/MgAlO_x-LDH catalysts loaded Ni foam reactor with heat recovery is proposed for highly efficient and stable CO₂ reforming under direct concentrated solar irradiation. The temperature nonuniformity is reduced by 84.3% compared to powdered systems, which benefits from the high thermal conductivity of nickel foams. Overheating is also prevented, which leads to much less carbon deposition and relieved active sites aggregation. Ultrahigh light-to-fuel efficiency of 36.51% is achieved, which is much higher than that of traditional powdered systems (23.87%). Numerical simulation results have an excellent agreement with experiments and demonstrate that heat recovery can greatly improve CRM rates by 23.8%. This work opens new routes to achieve highly efficient, stable, and scalable solar-driven CO₂ reforming via Ni/MgAlO_x-LDH catalysts loaded Ni foam reactors with heat recovery.