Fabrication of SiO2 incorporated ordered mesoporous TiO2 composite films as functional Pt supports for photo-electrocatalytic methanol oxidation

Abstract

SiO₂ incorporated ordered mesoporous TiO₂ composite films (TS) have been fabricated on FTO glass through a sol–gel progress, and applied as a Pt catalyst support material for direct methanol fuel cells. In this work, we investigate the effects of a different SiO₂ doping content and calcination temperature on the structure and corresponding properties of the resulting TiO₂–SiO₂ films. Characterization techniques including X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) are used to characterize the synthesized films. Potentiostatic pulse electrodeposition is employed to deposit Pt on the ordered mesoporous TiO₂–SiO₂ films. The results reveal that the films possess a 2D hexagonal mesoporous structure and the Si elements are uniformly dispersed in the TiO₂ matrix. Moreover, an ordered mesoporous Pt/TiO₂–SiO₂ film electrode calcinated at 500 °C with 7.5 wt% of SiO₂ shows enhanced catalytic activity for methanol oxidation, due to the high photoelectric response and the special synergetic effects between Pt and the TiO₂–SiO₂ films under UV illumination.