Effects of iron and cerium in La1−yCeyCo1−xFexO3 perovskites as catalysts for VOC oxidation

Perovskite-type mixed oxides La1−yCeyCo1−xFexO3 with high specific surface area were prepared by reactive grinding. These catalysts were characterized by N2 adsorption, X-ray diffraction, oxygen storage capacity (OSC), H2-temperature-programmed reduction (TPR-H2), O2-, and CH3OH-temperature-programmed desorption (TPD). The catalytic performance of the samples for volatile organic compounds (VOC), CH3OH, CO and CH4 oxidation was evaluated. Cerium allows an enhancement of the reducibility of the B-site cations in perovskite structure during OSC and TPR-H2 and an increase in the amount of β-O2 desorbed during TPD-O2. As opposed to cerium, the addition of iron in the perovskite structure causes a drop in B-site cations reducibility and a decrease of the oxygen mobility in the bulk. As a consequence, the catalytic activity in VOC oxidation is enhanced by introduction of cerium and weakened by iron in the lattice.