以TiCl4为钛前驱体，采用沉淀法制备了氮掺杂和纯TiO2. X射线衍射（XRD）和N2吸附－脱附等温线表征结果表明：所制催化剂以锐钛矿相为主，具有介孔结构. X射线光电子能谱（XPS）证实掺杂的氮以系列NOx存在. 由紫外－可见漫反射吸收光谱（UV-Vis）可知：氮掺杂TiO2 ( N-TiO2 )在400～550nm的可见光区出现新的吸收带. 4-氯苯酚(4-CP)降解实验表明，N-TiO2的紫外和可见光催化活性均高于纯TiO2. N-TiO2具有较高紫外光活性的原因可归于催化剂中含有的NOx. NOx在不改变TiO2禁带宽度的情况下，拓展了它的感光范围，激发更多的光生电子和空穴参与反应，并可降低电子和空穴的复合几率，从而提高了催化剂的紫外光活性.
Nitrogendoped and pure TiO2 photocatalysts were synthesized by precipitation method using TiCl4 as titanium precursor. Both X-ray diffraction (XRD) and N2 adsorptiondesorption isotherms show that the asprepared samples consis of anatase phase except for trace brookite phase with mesoporous structure. X-ray photoelectron spectroscopy(XPS) confirms that the incorporated nitrogen element exists as the chemical state of NOx. The UV-Vis diffuse reflection absorption spectra (UV-Vis) reveal that the nitrogendoped TiO2 shows a new absorption region at 400-550nm. The photocatalytic activities of the nitrogendoped TiO2 utilized for the photodegradation of 4-chlorophenol (4-CP) are higher than those of the pure TiO2 under UV and visible light irradiation. The improved photocatalytic activities under UV light irradiation of the nitrogendoped TiO2 are attributed to the presence of NOx. With no influence on the energy gap of TiO2, NOx can extend the optical response of TiO2, excite more photoinduced electronsholes for photocatalysis and reduce the recombination probabilities of carriers.
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