Porous Co-based spinel oxide prepared by soft-template method for ethanol oxidation

Abstract

The porous Co-based spinel composite oxides containing different transition metals (Cu, Fe, Ni, Mn, and Ce) were prepared by soft-template method for ethanol complete oxidation in air. The physicochemical properties of the prepared oxides were characterized by XRD, BET, H2-TPR, and O2-TPD. The results indicate that the transition metal ions can be dissolved into the Co3O4 lattice to form Co-based spinel oxide, which promote surface reactive oxygen species to be formed on the corresponding catalyst. The prepared Co-based spinel oxides have developed pore structure, and the specific surface area is larger than 80 m2·g−1, even up to 132 m2·g−1. The porous structure and high specific surface area can be traced back to the used soft-template reagent, and the pore size distribution and specific surface area can also be affected by the used transition metals. The synergistic effect from porous structure and surface reactive oxygen species can effectively promote ethanol oxidation to final product CO2. The porous Co-based spinel oxide containing Ce exhibits superior ethanol catalytic oxidation activity and high stability, the ethanol catalytic oxidation conversion and oxidation final product CO2 selectivity reached 99.7% and 99.1% at 200 °C, respectively. The results indicated that the porous Co-based spinel oxide catalyst has potential application value in ethanol oxidation elimination from air.