Rozman Nejc, Škrlep Luka, Gaberšček Miran, Sever-Škapin Andrijana
Acta Chim Slov. 2014;61(3):506-16.
Titania nanoparticles were synthesized by employing the hydrothermal method and using TiOSO(4) as a titanium source. By varying pH between 0.5 and 1.0 and adding isopropanol to the hydrothermal reaction mixture, different mixtures of anatase, rutile, and brookite were obtained. The samples were also doped with nitrogen at different N concentrations using, respectively, urea, ammonium nitrate, and tripropylamine as nitrogen sources. The samples were characterized by X-ray powder diffraction, field emission scanning electron microscopy, infrared spectroscopy, UV-Vis diffuse reflectance spectroscopy and according to their specific surface area. Additionally, their photocatalytic activity was measured in a gas-solid reactor system. The results show that low pH favours rutile formation, whereas a higher pH yields mixed phase titania polymorphs. Isopropanol addition also favours rutile formation, and boosted the photocatalytic activity of the resulted particles. Contrary to most data in the literature, rutile turned out to be the more active phase in the present investigation. Nitrogen doping, on the other hand, did not contribute to higher photocatalytic activity, but was rather detrimental to it.
采用水热法并以硫酸氧钛（TiOSO₄）作为钛源合成了二氧化钛纳米颗粒。通过将水热反应混合物的pH值在0.5至1.0之间变化并添加异丙醇，得到了锐钛矿、金红石和板钛矿的不同混合物。还分别使用尿素、硝酸铵和三丙胺作为氮源，以不同的氮浓度对样品进行氮掺杂。通过X射线粉末衍射、场发射扫描电子显微镜、红外光谱、紫外可见漫反射光谱以及根据其比表面积对样品进行了表征。此外，在气固反应器系统中测量了它们的光催化活性。结果表明，低pH值有利于金红石的形成，而较高的pH值会产生混合相的二氧化钛多晶型物。添加异丙醇也有利于金红石的形成，并提高了所得颗粒的光催化活性。与文献中的大多数数据相反，在本研究中，金红石被证明是活性更高的相。另一方面，氮掺杂并没有提高光催化活性，反而对其有不利影响。
