Ce0.8Sn0.2O2−–C composite as a co-catalytic support for Pt catalysts toward methanol electrooxidation

Ce 0.8 Sn 0.2 O 2− δ solid solution is fabricated using a simple one-step solvothermal method. The synthesized solid solution mixed with Vulcan XC-72 carbon black (denoted by Ce 0.8 Sn 0.2 O 2− δ –C) is employed as a co-catalytic support for Pt catalysts toward methanol electrooxidation. X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, N 2 adsorption/desorption and temperature programmed reduction (TPR) are used to characterize the properties of Ce 0.8 Sn 0.2 O 2− δ solid solution. The results show that Ce 0.8 Sn 0.2 O 2− δ possesses a high specific surface area, an enhanced conductivity and a high oxygen storage capacity (OSC). Pt catalysts grown around Ce 0.8 Sn 0.2 O 2− δ on carbon black form a special Pt–Ce 0.8 Sn 0.2 O 2− δ –C triple junction structure, and their electrocatalytic properties are investigated in detail by a series of electrochemical methods. As compared with Pt/CeO 2 –C and commercial Pt/C catalysts, Pt/Ce 0.8 Sn 0.2 O 2− δ –C catalyst exhibits superior electrocatalytic activity and long-term stability for methanol electrooxidation in acid media. The origin of the enhanced electroctatlytic properties for Pt/Ce 0.8 Sn 0.2 O 2− δ –C is closely related to the OSC of Ce 0.8 Sn 0.2 O 2− δ and the triple junction structure.