Photothermal catalytic dry reforming of methane over Ce-promoted Ni/NiO heterostructure

Abstract

Photothermal catalytic dry reforming of methane (DRM) provides a sustainable carbon conversion route, but the syngas production rates remain unsatisfactory under low-temperature conditions. This study reported a layered double hydroxide-derived Ni–NiO heterojunction catalyst with optimized electronic environments via Ce doping. The Ce-doped Ni–NiO catalyst exhibited excellent photothermal DRM performance, with H₂ and CO production rates of 93.90 and 114.25 mmol g⁻¹ min⁻¹, respectively, and superior 12-h stability. Mechanistic studies revealed that the Ni–NiO heterojunction activated CH₄ and CO₂ to form CH_x* and O* species, while Ce doping promoted the coupling of these intermediates to CH₃O*, enhancing syngas generation. This strategy effectively bonded the intermediate species generated from the reactants, thereby enhancing the conversion of CH₄ and CO₂ into syngas.