Effect of structural properties of mesoporous Co 3 O 4 catalysts on methane combustion

Highly ordered 2D and 3D-Co 3 O 4 catalysts were prepared using SBA-15 and KIT-6 as templates. Nano-Co 3 O 4 catalyst was obtained by calcination of cobalt nitrate as a comparison. The BET surface area of nano- Co 3 O 4 , 2D-Co 3 O 4 and 3D-Co 3 O 4 catalysts was 16.2, 63.9 and 75.1 m 2 /g, respectively. All the catalysts were tested for the total combustion of methane and their catalytic performance was in order of 3D-Co 3 O 4 ( T 90 =355 °C)>2D-Co 3 O 4 ( T 90 =383 °C)>nano-Co 3 O 4 ( T 90 =455 °C). It was also found that the order of the areal specific reaction rates for the combustion of methane follow the same order of total activity. The characterization result demonstrated that enhanced catalytic performance of methane of the 2D-Co 3 O 4 and 3D-Co 3 O 4 catalysts was due to their pronounced reducibility and abundant active Co 3+ species which was caused by the preferential exposure of {220} crystal planes in 3D-Co 3 O 4 and 2D-Co 3 O 4 catalysts compared to the nano-Co 3 O 4 .