CO and C3H8 oxidation activity of Pd/ZnO nanowires/cordierite catalyst

•The potential of using ZnO nanowires as monolith catalyst carrier was investigated.•ZnO nanowire structures have greater effective porosity and more open surface area.•CO and C3H8 oxidation activities of Pd/ZnO nanowires/cordierite were examined.•ZnO nanowires are promising materials for the use as a catalyst wash-coat.

Using nanowires grown on monolith cordierite as catalyst wash-coat is a new concept. ZnO nanowires array has different pore-region diffusion of reactants in the catalyst media because it can have greater effective porosity and average diffusion length scale than traditional catalyst carrier. Also, thickness of ZnO nanowires array is less than conventional wash coat. ZnO nanowires were grown on monolith cordierite channels, and Pd was impregnated on the nanowires. The catalyst structure was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and atomic absorption spectrometry (AAS). The activity performance of Pd/ZnO nanowires catalyst for C3H8 and CO was examined under lean, stoichiometric and rich conditions. T50 was achieved under stoichiometric condition of gas mixture for C3H8 and CO at 400 °C and 235 °C, respectively.