Ananpattarachai Jirapat, Kajitvichyanukul Puangrat, Seraphin Supapan
Department of Environmental Engineering, King Mongkut's University of Technology Thonburi, Bangkok, Thailand.
J Hazard Mater. 2009 Aug 30;168(1):253-61. doi: 10.1016/j.jhazmat.2009.02.036. Epub 2009 Feb 20.
Nitrogen-doped TiO(2) was developed to enable photocatalytic reactions using the visible range of the solar spectrum. This work reports on the synthesis, characterisation and kinetic study of interstitial N-doped TiO(2) prepared by the sol-gel method using three different types of nitrogen dopants: diethanolamine, triethylamine and urea. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and UV-visible spectroscopy were used to analyse the titania. Different interstitial N-doped TiO(2) properties, such as absorption ability in the UV-visible light region, redshift in adsorption edge, good crystallisation and composition ratio of titania structures (anatase and rutile) could be obtained from different nitrogen dopants. Amongst investigated nitrogen precursors, diethanolamine provided the highest visible light absorption ability of interstitial N-doped TiO(2) with the smallest energy bandgap and the smallest anatase crystal size, resulting in the highest efficiency in 2-chlorophenol degradation. The photocatalytic activity of all N-doped TiO(2) can be arranged in the following order: TiO(2)/diethanolamine>TiO(2)/triethylamine>TiO(2)/urea>un-doped TiO(2). The initial rate of 2-chlorophenol degradation using the interstitial N-doped TiO(2) with diethanolamine was 0.59 mg/L-min and the kinetic constant was 2.34 x 10(-2)min(-1) with a half-life of 98 min. In all cases, hydroquinone was detected as a major intermediate in the degradation of 2-chlorophenol.
开发了氮掺杂二氧化钛,以实现利用太阳光谱可见光范围的光催化反应。本文报道了采用溶胶 - 凝胶法,使用三种不同类型的氮掺杂剂(二乙醇胺、三乙胺和尿素)制备的间隙氮掺杂二氧化钛的合成、表征及动力学研究。利用X射线衍射、扫描电子显微镜、透射电子显微镜、X射线光电子能谱和紫外 - 可见光谱对二氧化钛进行了分析。不同的氮掺杂剂可以得到间隙氮掺杂二氧化钛的不同性质,如紫外 - 可见光区域的吸收能力、吸附边的红移、良好的结晶性以及二氧化钛结构(锐钛矿和金红石)的组成比。在所研究的氮前驱体中,二乙醇胺使间隙氮掺杂二氧化钛具有最高的可见光吸收能力、最小的能带隙和最小的锐钛矿晶体尺寸,从而在2 - 氯苯酚降解中具有最高效率。所有氮掺杂二氧化钛的光催化活性可按以下顺序排列:TiO₂/二乙醇胺>TiO₂/三乙胺>TiO₂/尿素>未掺杂的TiO₂。使用含二乙醇胺的间隙氮掺杂二氧化钛降解2 - 氯苯酚的初始速率为0.59 mg/L·min,动力学常数为2.34×10⁻² min⁻¹,半衰期为98 min。在所有情况下,对苯二酚被检测为2 - 氯苯酚降解的主要中间产物。