Highly stable and selective CoxNiyTiO3 for CO2 methanation: Electron transfer and interface interaction

Abstract

CO2 methanation with Sabatier reaction is an effective way to convert the greenhouse gases into valuable industrial product. In this work, we designed and developed a stable and effective Co modified NiTiO3 catalyst. The best catalyst exhibits high CO2 conversion (86 %) and high methane selectivity (nearly 100 %), which can work continuously for 16?h without significant deactivation at 350 ℃. As evidenced by various characterization methods, like XPS, H2-TPD and CO2-TPR, Co doping is found to influence the electron distribution of the catalyst, change the size of metal particle and the interaction of metal and support, which in turn has positive impact on methanation performance, while NiTiO3 support improves the ability to capture CO2 because of its abundant basic oxide and oxygen vacancies after reduction. Cobalt modification proved to be a potential way to construct Ti-O-Ni interfacial structure, and increase the hydrogen activation sites and carbon dioxide activation site simultaneously. This work may provide useful information for designing and optimizing multi-metal modified catalyst for CO2 methanation.