Efficient photothermal catalytic methane dry reforming over rich oxygen vacancy catalysts†

The catalysts of Ni nanoparticles supported on ZrO₂, La₂O₃ and La₂Zr₂O₇ were prepared and employed in photothermal catalytic DRM. High yield of H₂ and CO (76.2 and 99.1 mmol g⁻¹ min⁻¹) and excellent durability (50 h) were achieved merely under focused light irradiation. 10Ni/La₂O₃ exhibited better resistance to carbon deposition compared to 10Ni/ZrO₂ and 10Ni/La₂Zr₂O₇. Structural characterization and experimental data indicated that La₂O₃ has abundant oxygen vacancies, which can adsorb and activate CO₂ to produce reactive oxygen species. Oxygen species transfer to nickel nanoparticles through the strong Ni–La₂O₃ interface to accelerate carbon oxidation. The experimental results indicated that light illumination can not only drive DRM reactions through photothermal conversion, but also improve catalytic activity by reducing the activation energy of reaction molecules and stability by increasing the oxygen vacancies.