In situ poly(methyl methacrylate)-templating generation and excellent catalytic performance of MnOx/3DOM LaMnO3 for the combustion of toluene and methanol

Rhombohedrally crystallized three-dimensionally ordered macroporous (3DOM) LaMnO3 supported MnOx (5, 8, 12, 16 wt% MnOx/3DOM LaMnO3) catalysts were prepared using the in situ tryptophan-assisted 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 and methanol. It is shown that the MnOx/3DOM LaMnO3 samples displayed a 3DOM architecture and a high surface area of 19-31 m(2)/g. The 12 wt% MnOx/3DOM LaMnO3 sample showed the highest oxygen adspecies concentration and the best low-temperature reducibility as well as the highly dispersed MnOx particles on the LaMnO3 surface, giving the highest TOF values of 7.9 x 10(-6) s(-1) for toluene combustion at 160 degrees C and 7.3 x 10(-6) s(-1) for methanol combustion at 80 degrees C. The apparent activation energies of the MnOx/3DOM LaMnO3 catalysts were 61-62 and 48-54 kJ/mol for toluene and methanol combustion, respectively. It is concluded that the excellent catalytic performance of 12 wt% MnOx/3DOM LaMnO3 was associated with its highest oxygen adspecies concentration, best low-temperature reducibility, and strong interaction between MnOx and 3DOM LaMnO3. (C) 2013 Elsevier B.V. All rights reserved.