A facile approach for the preparation of biomorphic CuO-ZrO 2 catalyst for catalytic combustion of methane

Abstract

A series of novel biomorphic CuO-ZrO 2 catalysts were prepared using a cotton bio-template and compared with conventional CuO-ZrO 2 catalysts. The physical and chemical properties of the as-obtained catalysts were characterized by techniques including X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), H 2-temperature programmed reduction (H 2-TPR), and O 2-temperature programmed desorption (O 2-TPD). The catalytic combustion of methane was chosen as the probe reaction. The results suggested that the bio-template method prepared porous biomorphic CuO-ZrO 2 catalysts consist of hollow microtubes. Comparing with conventional CuO-ZrO 2 catalysts, biomorphic CuO-ZrO 2 catalysts displayed better reducibility and oxygen mobility, stronger metal-oxides synergistic effect, appropriate particle size distribution, and lower activation energy. The crystalline state of zirconia transformed from a single crystallite phase of t-ZrO 2 into a complex of m-ZrO 2 and t-ZrO 2 after introducing the bio-template. With proper CuO content (20 mol%), the biomorphic CuO-ZrO 2 catalyst displayed preponderant properties. The compensation of surface lattice oxygen from bulk lattice oxygen was more available at high reaction temperatures. © 2011 Elsevier Ltd. All rights reserved.