Ni-doping-induced oxygen vacancy in Pt-CeO2 catalyst for toluene oxidation: Enhanced catalytic activity, water-resistance, and SO2-tolerance

It is a challenge to enhance the catalytic activity of the oxidation of volatile organic compounds (VOCs) and the poison-tolerance capacity in the practical application. Here, we report the construction of Pt/Ni-CeO2 catalyst via Ni doping, which exhibited the excellent toluene catalytic performance, as well as remarkably improved water-resistance and SO2-tolerance. The electron energy loss spectroscopy and density functional theory calculations demonstrated that the doped Ni species induced the generation of abundant oxygen vacancies from bulk to the surface, improving the redox property, activation of oxygen species, and adsorption capacity of toluene molecules. Moreover, the Pt-NiO interfacial structure was formed by the thermal-driven Ni species to the adjacent Pt species, which could modify the electronic and chemical properties of Pt, thus restraining the adsorption of water and SO2 molecules. This investigation provides new insights into the activation of oxygen species via oxygen vacancies, and anti-poison activity via surface modification engineering for catalyst development in practical applications.