氮掺杂纳米TiO_2光催化氧化NO_2效率的研究(英文)

Study on Photo-Catalytic Efficiency of Nitrogen-Doped Nano-TiO_2

通过机械化学方法对纳米TiO2进行掺氮改性后,研究了煅烧温度和煅烧时间对纳米TiO2在模拟日光条件下光催化氧化NO2性能的影响。结果表明,当煅烧温度为500℃时,光催化效率随煅烧时间的延长而增加;但当煅烧温度为600和700℃时,光催化效率随煅烧时间的延长而降低,这主要是由于煅烧温度的增加使得纳米TiO2由锐钛矿型转变为金红石型。当煅烧温度为500℃时,煅烧时间从3h延长到5h,光催化效率从51.5%提高到67.0%,这是P25光催化效率的135%。

Nitrogen-doped nano-TiO2 was prepared via a mechanochemical process. The effects of different calcination temperatures and time on the photo-catalytic efficiency of nitrogen-doped nano-TiO2 were investigated under simulated sunlight irradiation condition for photo-oxidization reaction of nitrogen dioxide. The experimental results show that the photo-catalytic efficiency increased with the increase of calcination time at the calcination temperature of 500 °C, and decreased with the increase of time at the calcination temperature of 600 or 700 °C. This was attributed to the fact that anatase was transformed to rutile at higher calcination temperature. When the calcination time was from 3 to 5 h at 500 °C, the photo-catalytic efficiency increased from 51.5% to 67.0%, which was 135% of that of P25.