Dual nanoparticles with rich Ni–CeO2 interfaces for efficient photothermal catalytic CO2 reduction by CH4

Abstract

Reducing CO2 by CH4 (CRM) is of great significance for alleviating greenhouse effects and fuel shortages. However, the high energy consumption and low yield of fuel, as well as the deactivation of Ni based catalysts constrained its development. Herein, a novel Ni–CeO2/Al2O3 catalyst for photothermal catalytic CRM merely upon focused light irradiation was reported. Very high yield of H2 and CO (80.2 and 96.3 mmol min−1 g−1) and excellent catalytic durability were achieved. The results of UV-VIS-IR diffuse reflectance spectra and experimental test indicate that high yield of H2 and CO originates from efficient photothermal conversion and the molecular activation effect of light. More importantly, Ni–CeO2/Al2O3 exhibits better carbon deposition resistance than Ni/Al2O3. The structural characterization and experimental evidences reveal that the active lattice oxygen in CeO2 nanoparticles can be transferred to Ni nanoparticles via Ni–CeO2 interface to accelerate carbon oxidation and form oxygen vacancies. The formed oxygen vacancies can re-adsorb and activate CO2 to form new active lattice oxygen.