Laser‐Constructed RuO ₂ /Fe ₂ O ₃ Composites for Efficient Photothermal Catalytic CO ₂ Methanation Reaction

Abstract Photothermal catalytic methanation of carbon dioxide (CO ₂ ) is a promising and sustainable method for carbon resource utilization. The efficiency of this process hinges on enhancing the photothermal conversion capacity and precisely designing the catalytically active sites. Here, a laser synthesis strategy is proposed to construct the RuO ₂ /Fe ₂ O ₃ heterostructure by laser etching to build a grooved Fe ₂ O ₃ substrate and depositing RuO ₂ nanoparticles. RuO ₂ /Fe ₂ O ₃ combines the wide‐spectrum absorption capacity of Fe ₂ O ₃ substrates (reaching 209.2 °C under light irradiation with a light intensity of 1.83 W cm ⁻² ) and the catalytic activity of RuO ₂ , enabling CO ₂ to have the ability of selective hydrogenation. Combined with the catalyst characterization and the catalytic experimental results, RuO ₂ /Fe ₂ O ₃ is confirmed to be a photothermal catalyst with excellent catalytic performance and stability for CO ₂ methanation (CH ₄ selectivity and yield are 96% and 795 µmol cm ⁻² h ⁻¹ , respectively). This work provides a versatile platform for designing multi‐functional catalytic systems by laser‐assisted strategy, opening new avenues for solar‐driven CO ₂ valorization.