Manganese-doped CeO_2 nanocubes as highly efficient catalysts for styrene epoxidation with TBHP

摘要

CeO2-based nanocubes doped with different contents of manganese were fabricated via hydrothermal method and were used as catalysts in the selective oxidation of styrene with tert-butyl hydroperoxide (TBHP). Several characterization instruments and methods were employed to study the structure, surface, composition, and reducibility of these nanocubes. It was found that Mn was doped into ceria lattice to form Ce-based solid solutions, leading to an enrichment of oxygen defects, an enhancement of specific surface area and reducibility of CeO2 nanocubes. It was also found that the amount of Mn is a vital factor affected the concentration of oxygen vacancies and surface Mn3+ percentage, determining the catalytic activity in the epoxidation of styrene. Ce0.96Mn0.04O2 showed the highest catalytic activity and excellent stability, which was chiefly owing to the highest content of surface Mn3+ ions and the enrichment of oxygen vacancies.