Facet-Dependent Activity of Co3O4 Catalyst for C3H8 Combustion

Clarifying the facet-dependent activity of Co3O4 towards C3H8 combustion is of great importance to have a deep understanding of reaction mechanism and develop highly active Co3O4 based catalysts for light hydrocarbon combustion. In this work, four different Co3O4 nanocatalysts which dominantly exposed {100}, {111}, {110} and {112} facets, respectively, were synthesized via hydrothermal method and further tested in C3H8 combustion. The catalytic activity of different crystal planes varied as the order of {111}>{100}>{110}>{112}. The Co3O4 catalyst with {111} facets exhibited the best catalytic performance with T-50 and T-90 as low as 209 and 239 degrees C, respectively. DRIFT and DFT calculations revealed that the facile activation of C-H bond on Co3O4 {111} planes is responsible for the high activity. Moreover, the higher activity of lattice oxygens and easy activation of gas phase oxygen could also contribute to the excellent catalytic performance.