关键词: 水热炭; TiO₂, 溶胶–凝胶法, 甲基橙, 光催化

Abstract:

Using hydrochars as template, TiO₂ photocatalysts were prepared by the sol-gel method. The samples were characterized with X-ray diffraction (XRD), Fourier infrared spectrum (FT-IR), scanning electron microscope (SEM) and BET specific surface area measurement. The photocatalytic activity was investigated by degradation of methyl orange (MO) as target pollutant in the solution. The results showed that HTC-TiO₂ remained anatase type at high calcination temperature due to the higher thermal stability than TiO₂. The TiO2 particles were almost uniformly dispersed on the surface of HTC. HTC-TiO₂ had smaller crystal sizes, bigger specific surface area and the flake structure, which had the same structure character as the hydrochars micro-structure and was beneficial to improve the photocatalytic activity. The degradation rate of MO under 550 W iodine-tungsten lamp illumination for 2 hours was 40.6% in presence of HTC-TiO₂ calcined at 450ºC, which increased by 1.5 times more than those in presence of TiO₂ (16.2%).

Key words: hydrochars, TiO₂, sol-gel method, methyl orange, photocatalysis