Synthesis of Highly Efficient CuCeZr Catalyst Derived from UiO-66 Precursor for CO Oxidation

Abstract

CuCeZr samples derived from UiO-66 precursor were achieved. The effect of treatment temperature (500–800 °C) and prepared methods (impregnation method and one pot method) on the structure and CO catalytic performance of CuCeZr samples was investigated. The samples were measured by N2 sorption isotherms, X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma optical emission spectroscopy (ICP-OES) and H2-temperature program reduction (H2-TPR). It was found that calcination temperature and prepared way intensely influenced physicochemical parameters, oxygen vacancy and low-temperature reduction ability of CuCeZr catalysts. CuCeZr catalyst prepared by impregnation method at 700 °C (CuCeZr700-i) exhibited highest catalytic performance for CO oxidation (T100 = 140 °C). High dispersed easily reducible surface species, low valence Cu species, surface lattice oxygen and oxygen vacancy were thought to improve catalytic performance. In addition, CuCeZr700-i presented a good cycle performance, water resistance, and poor stability. The structure of catalyst after reaction was characterized. It was found that the long reaction time led to the decrease of low-temperature easily reducible surface copper species, thereby resulting in slight decrease of reaction stability.