自燃烧法合成氮、铁共掺杂TiO_2及其可见光光催化活性

Synthesis of N-Fe-codoped TiO_2 by Auto Combusting Method and Its Visible Light Photocatalytic Activity

以硫酸钛、硝酸铁、尿素为原料,采用自燃烧法制备了氮、铁共掺杂的纳米TiO2粉体。XRD结果显示氮、铁共掺杂的纳米TiO2主要为锐钛矿相。当氮、铁共掺杂时,二氧化钛光谱吸收红移至可见区。XPS结果表明:铁进入TiO2的晶格中形成浅势,氮则取代氧原子形成了N-Ti键,它们的形成降低了二氧化钛的带隙,从而提高了可见光区的光催化能力。当氮、铁对钛的物质的量比分别为0.5%和0.6%时,其在可见光下降解亚甲基蓝的降解率分别是单掺杂和纯TiO2的1.4和3倍。

Nitrogen and iron co-doped TiO2 powders were prepared by auto combusting method using titanium sulphate, ferric nitrate, urea and malic acid as raw materials. The XRD results showed that the anatase is main phase for co-doping nitrogen and iron TiO2. UV-vis spectroscopy of co-doping nitrogen and iron TiO2 indicated that the absorption onset red-shifts to the visible light region. XPS results revealed that the Ti-N bonds and Fe2O3 have formed which could extend the absorption spectra to visible light region and enhance visible light photocatalytic activity. The degradation rate of methylene blue over N0.8F0.6T is about 1.4 to 3.0 times higher than that for other doped samples and undoped TiO2.