Electron-Deficient Ru ^δ+ Sites Coupled with Lattice Oxygen at Ru/BaTiO ₃ Interfaces Enable Efficient Photothermal Methane Dry Reforming

Abstract

Solar-driven dry reforming of methane (DRM) represents a promising pathway for syngas production, yet its practical application is challenged by insufficient activity and rapid deactivation. Here, we report a Ru/BaTiO 3 catalyst with interfacial electron-deficient Ru δ+ sites and dynamic lattice oxygens for efficient photothermal DRM. Under light irradiation, the catalyst delivers H 2 and CO production rates of 68.43 and 85.18 mol g Ru –1 h –1, a methane turnover frequency of 1.08 s –1, a light-to-chemical energy efficiency of 14.2%, and stable operation over 100 h. Combined experimental and theoretical studies reveal that interband electronic transition-induced electrons migrate from Ru nanoparticles to BaTiO 3, enriching Ru δ+ sites that drive stepwise C–H bond cleavage in CH 4 . Meanwhile, lattice oxygens from BaTiO 3 oxidize CH* to CHO*, generating oxygen vacancies that convert CO 2 into CO and are refilled by the incorporation of an O*, sustaining a closed redox cycle. This dual mechanism of light-triggered electronic modulation and lattice oxygen participation launches a paradigm for optimizing DRM pathways. The findings highlight the critical role of nonplasmonic metal–support interfaces in solar-driven CH 4 /CO 2 conversion.