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.