Chloroplast-Mimicking Interfaces on In Situ Derived La-Ni Based Perovskite for Solar-Driven CO₂ Reduction to CH₄

Artificial photosynthesis technology holds great promise for sustainable energy conversion and value-added chemical synthesis, yet integrating efficient light absorption with high product selectivity remains a major challenge. This study constructs an Ni-La₂O₃/La₂NiO₄ catalyst through in situ perovskite derivation that mechanistically and functionally mimics the chloroplast for artificial photosynthesis by coupling photo and photothermal catalysis with the integration of broad-spectrum light harvesting, directional charge transfer, as well as CO₂ adsorption and hydrogenation. Three functional interfaces are formed: La₂O₃-La₂NiO₄ (Z-scheme), Ni-La₂NiO₄ (Schottky junction), and La₂O₃(adsorption)-Ni(activation). The two heterojunctions facilitate electron transfer to metallic Ni nanoparticles, which activates H⁺ to form an NADPH-like surface Ni-H species by enabling the collection of photo and photothermal generated electrons. Meanwhile, the Lewis-basic La₂O₃ captures CO₂ and promotes its activation at the La₂O₃-Ni interface. In CO₂-to-CH₄ conversion, Ni-La₂O₃/La₂NiO₄ demonstrates an exceptional CH₄ production rate of 9.96 µmol h^-1 g^-1 and a selectivity of 92.5% under natural conditions (i.e., AM 1.5 irradiation, ambient temperature, and atmospheric pressure) without external assistance, which outperforms pure La₂NiO₄ by 10.2 and 4.6 times, respectively. This work advances a new strategy for efficient solar-to-fuel conversion.