Three-dimensional Mn–Cu–Ce ternary mixed oxide networks prepared by polymer-assisted deposition for HCHO catalytic oxidation

Abstract

Mn–Cu–Ce ternary mixed oxide networks with a three-dimensional (3D) structure were successfully fabricated by a polymer-assisted deposition method. Ethylenediaminetetraacetic acid (EDTA) and a water-soluble polymer, polyethylenimine (PEI), were utilized as binding ligands. PEI and EDTA could not only work as the initial network structure but also sequester the metals to provide a homogeneous solution. The ternary mixed oxide networks with oxide nanoparticles highly dispersed in the framework were obtained after drying and heat treatment. Characterization of the catalysts indicates the formation of a ceria-based solid solution that functions as the oxygen supply center for active oxygen transmission. Moreover, excess Cu and Mn oxides highly dispersed over the ceria-based solid solution could form a mixed oxide structure and serve as active centers of catalytic oxidation with a strong capacity to activate the HCHO molecules. Because of their 3D network structure, abundant active oxygen, and good oxygen transmission and storage ability, these ternary mixed oxide networks exhibit high, stable catalytic activity for HCHO oxidation for 120 h with 100% oxidation conversion at 170 °C. These ternary mixed oxide networks will have good potential to be applied in various catalytic reactions. The polymer-assisted deposition approach could be further employed to develop a remarkably broad range of composite metal oxide materials for technical applications.