Fabrication of Heterostructural FeNi3‐Loaded Perovskite Catalysts by Rapid Plasma for Highly Efficient Photothermal Reverse Water Gas Shift Reaction

Metal-semiconductor heterostructured catalysts have attracted great attention because of their unique interfacial characteristics and superior catalytic performance. Exsolution of nanoparticles is one of the effective and simple ways for in-situ growth of metal nanoparticles embedded in oxide surfaces and their favorable dispersion and stability. However, both high-temperature and a reducing atmosphere are required simultaneously in conventional exsolution, which is time-consuming and costly, and particles often agglomerate during the process. In this work, Ca_0.9Ti_0.8Ni_0.1Fe_0.1O_3-δ (CTNF) is exposed to dielectric blocking discharge (DBD) plasma at room temperature to fabricate alloying FeNi₃ nanoparticles from CTNF perovskite. FeNi₃-CTNF has outstanding catalytic activity for photothermal reverse water gas shift reaction (RWGS). At 350 °C under full-spectrum irradiation, the carbon monoxide (CO) yield of FeNi₃-CTNF (10.78 mmol g^-1 h^-1) is 11 times that of pure CaTiO₃(CTO), and the CO selectivity is 98.9%. This superior catalytic activity is attributed to the narrow band gap, photogenerated electron migration to alloy particles, and abundant surface oxygen vacancies. The carbene pathway reaction is also investigated through in-situ Raman spectroscopy. The present work presents a straightforward method for the exsolution of nanoalloys in metal-semiconductor heterostructures for photothermal CO₂ reduction.