Synthesis and characterization of carbon doped TiO2 photocatalysts supported on stainless steel mesh by sol-gel method

Abstract

This study synthesized pure anatase carbon doped TiO₂ photocatalysts supported on a stainless steel mesh using a sol-gel solution of 8% polyacrylonitrile (PAN)/dimethylformamide (DMF)/TiCl₄. The influence of the pyrolysis temperature and holding time on the morphological characteristics, particle sizes and surface area of the prepared catalyst was investigated. The prepared catalysts were characterized by several analytical methods: high resolution scanning electron microscopy (HRSEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), and X-ray photoelectron spectroscopy (XPS). The XRD patterns showed that the supported TiO₂ nanocrystals are typically anatase, polycrystalline and body-centered tetragonal in structure. The EDS and XPS results complemented one another and confirmed the presence of carbon species in or on the TiO₂ layer, and the XPS data suggested the substitution of titanium in TiO₂ by carbon. Instead of using calcination, PAN pyrolysis was used to control the carbon content, and the mesoporosity was tailored by the applied temperature. The supported TiO₂ nanocrystals prepared by pyrolysis at 300, 350, and 400oC for 3 h on a stainless steel mesh were actual supported carbon doped TiO₂ nanocrystals. Thus, PAN/DMF/TiCl₄ offers a facile, robust sol-gel related route for preparing supported carbon doped TiO₂ nanocomposites.