Structural characteristics and catalytic performance of nanostructured Mn-doped CeO2 solid solutions towards oxidation of benzylamine by molecular O-2

摘要

This work reports a thorough investigation of nanosized Mn-doped ceria (Ce0.7Mn0.3O2-delta, CM) as an efficient catalyst for oxidation of benzylamine under solvent-free conditions. These catalysts were prepared by a coprecipitation method followed by calcination at 773 and 1073 K. Effect of Mn doping was examined by a variety of characterization techniques. XRD results confirmed formation of single-phase Ce-O-Mn solid solution, and TEM studies showed nanosized nature of particles. BET surface area of CeO2 was significantly enhanced after Mn incorporation. Raman, XPS and H-2-TPR results revealed that Mn cations in ceria lattice increase concentration of structural oxygen vacancies and reducibility of ceria. Among various catalysts, the CM calcined at 773 K exhibited a high conversion (similar to 71%), product selectivity (similar to 99.8%), and excellent stability. The better performance has been proved to be due to synergetic interaction between Ce and Mn ions thereby enhanced surface area, improved reducibility, and increased surface adsorbed oxygen species. (C) 2016 Elsevier Ltd. All rights reserved.