Efficient and Robust Heterostructure CeZrO_x/NiO-Ni Inverse Catalyst for Sustainable Photothermal CO₂ Methanation

Photothermal CO₂ methanation offers a route to store renewable energy as synthetic methane, yet conventional Ni catalysts typically require intense light or auxiliary heating and show poor tolerance to intermittency. Here, we report a CeZrO_x/NiO-Ni inverse catalyst via a heterostructure engineering strategy, featuring a protective NiO interlayer. This tailored architecture achieves 83% single-pass CO₂ conversion with >99% CH₄ selectivity under 0.71 W cm^-2 irradiation in a continuous-flow system, without external heating. Notably, it delivers a CH₄ space-time yield of 464 mmol·g_cat ^-1·h^-1 under natural concentrated sunlight and maintains robust performance over repeated light-dark cycles, extended air storage, and 100-g scaled synthesis, demonstrating its potential compatibility with intermittent renewable energy. Mechanistic studies reveal that the sub-nanometer NiO layer on Ni domains enhances LSPR-induced heating and hot-carrier injection while establishing a favorable CeZrO_x/NiO-Ni band alignment for charge separation. This heterointerface further promotes CO₂ activation via *COOH intermediates and electron-mediated pathways, thereby amplifying photothermal synergy under low-intensity illumination. This work highlights the critical role of interfacial engineering in advancing solar-driven energy conversion and provides a catalyst-level design strategy that could help bridge lab-scale innovation and future practical applications.