Regulation of metal-support interface of Ni/CeO₂ catalyst and the performance of low temperature chemical looping dry reforming of methane

Interface regulation is an effective strategy to improve the interaction between carrier and active metal center, which can improve the catalytic activity and oxygen storage capacity of the catalysts. In this paper, Ni/CeO₂ catalysts supported on CeO₂ with different morphologies (nanorods, nanocubes, nanoctahedrons and nanopolyhedrons) were synthesized. The structure dependence of the catalysts for the low temperature chemical looping dry reforming of methane (CL-DRM) was investigated. The characterization results showed that Ni species were highly dispersed on the surface of CeO₂ carrier, and some Ni ions entered the CeO₂ lattice, resulting in the increase of oxygen vacancies. The Ni/ceria-rods catalyst had the highest reducibility, the most oxygen vacancies and the highest oxygen storage capacity. The irregular CeO₂ nano single crystal of about 10.3 nm in the Ni/ceria-polyhedra led to high specific surface area and high reducibility which exhibited the highest redox activity and redox stability in low-temperature chemical looping dry reforming of methane at 550 ℃. This study provided a new strategy for the design of efficient metal/CeO₂ catalysts, which was expected to promote the application of cerium-based catalysts in chemical looping technology.