Highly Dispersed Cu ⁺ ‐CeO ₂ for Enhanced Solar‐ driven Dry Reforming of Methane over Ni‐based Catalysts

ABSTRACT Solar‐driven dry reforming of methane (DRM) represents a sustainable route to convert greenhouse gases into syngas, which enables efficient solar energy storage and cascaded utilization. However, this process is often limited by insufficient reactivity and low light‐to‐fuel efficiency. Herein, by anchoring highly dispersed electron‐deficient Cu ⁺ species on defective CeO ₂ (Cu ⁺ ‐CeO ₂ ) via a high‐temperature H ₂ induction strategy (750°C), we designed an efficient Ni‐based catalyst for solar‐driven dry reforming of methane. The as‐obtained Ni‐Cu(750)/CeO ₂ catalyst enhanced syngas production rate with a high light‐to‐fuel efficiency of 42.8% at 618°C, which significantly surpassed most state‐of‐the‐art photothermal DRM catalysts even under milder conditions. Mechanism studies revealed that high‐temperature H ₂ treatment promoted the formation of Cu ⁺ ‐O _v ‐Ce ³⁺ structures, which collectively modulated the electronic state to generate electron‐enriched Ni active sites. The synergy between electron‐rich Ni and Cu ⁺ ‐O _v ‐Ce ³⁺ enhanced visible‐light absorption and improved photothermal conversion. In situ DRIFTS studies demonstrated that Cu ⁺ ‐O _v ‐Ce ³⁺ structures selectively promoted the rapid decomposition and desorption of the HCOO ^* intermediate into CO, ensuring efficient active site cycling to achieve superior activity and stability in the photothermal DRM process. This work offers a generalized electronic structure engineering strategy for solar‐driven greenhouse gases utilization.