ZIF-67 derived lamellar nanoarray spinel as effective catalyst for toluene combustion

Active sites exposed to the surface of solid catalysts play a significant role in heterogeneous catalysis. In order to aggrandize the exposure of active sites by enhancing catalyst specific surface area, a hierarchically structured nanoarray that nickel–cobalt spinel oxide regularly arranged on the hollow polyhedral structure surface in vertical orientation was successfully designed. Moreover, the effect of nickel ions concentration on the surface defects of the catalyst was studied, and Ni-Co-2:1 sample possesses optimal catalytic activity, achieving 90% toluene conversion at 257 °C.