In situ PMMA-templating preparation and excellent catalytic performance of Co3O4/3DOM La0.6Sr0.4CoO3 for toluene combustion

Abstract

Rhombohedrally crystallized three-dimensionally ordered macroporous (3DOM) La0.6Sr0.4CoO3 (LSCO)-supported Co3O4 (x wt% Co3O4/3DOM LSCO; x=0, 2, 5, 8, and 10) were prepared using the in situ poly(methyl methacrylate)-templating strategy. Physicochemical properties of the materials were characterized by means of numerous analytical techniques, and their catalytic activities were evaluated for the combustion of toluene. It is shown that the x wt% Co3O4/3DOM LSCO samples displayed a 3DOM architecture and a high surface area of 29–32m2/g. Among the x wt% Co3O4/3DOM LSCO samples, the 8wt% Co3O4/3DOM LSCO sample possessed the highest adsorbed oxygen species concentration and the best low-temperature reducibility. The 8wt% Co3O4/3DOM LSCO sample showed the best catalytic performance for toluene combustion (the temperatures required for toluene conversions of 10, 50, and 90% were 158, 210, and 227°C at a space velocity of 20,000mL/(gh), respectively). The apparent activation energies (43–58kJ/mol) of the x wt% Co3O4/3DOM LSCO (x=0–10) samples were lower than those (59–67kJ/mol) of the 8wt% Co3O4/bulk LSCO and bulk LSCO samples. It is concluded that the excellent catalytic performance of 8wt% Co3O4/3DOM LSCO was associated with its high oxygen adspecies concentration, good low-temperature reducibility, and strong interaction between Co3O4 and LSCO as well as high-quality 3DOM structure.