以聚乙烯吡咯烷酮(PVP)为辅助剂，采用水热法制备了板钛矿TiO₂纳米颗粒。借助于多种测试仪器对所得样品进行了表征，如X射线衍射仪、拉曼光谱仪、扫描电镜、紫外漫反射光谱仪等。同时，在紫外光照射下，利用亚甲基蓝溶液降解实验评价了所得样品的光催化活性。实验结果表明，所得样品为单一相板钛矿TiO₂纳米颗粒。PVP在板钛矿TiO₂纳米颗粒形成过程中起到了稳定剂和分散剂作用。改变PVP用量，板钛矿TiO₂的颗粒尺寸先减小后增大，禁带宽度值维持在3.2~3.3 eV范围内。PVP的最佳用量为0.2 g，该条件下所得板钛矿TiO₂的纳米颗粒尺寸最小(约为21.0 nm)，光催化活性最高，即在紫外灯照射120 min后，对亚甲基蓝溶液的降解率高达96.4%。
Brookite TiO₂ nanoparticles were synthesized by hydrothermal method in the presence of polyvinylpyrrolidone (PVP) as auxiliary agent. The samples were characterized by X-ray diffractometer, Raman spectrometer, scanning electron microscope, UV diffuse reflectance spectrometer, etc. At the same time, the photocatalytic activity of the samples was evaluated by the photodegradation of methylene blue (MB) solution under UV light. Experimental results show that all the samples are single-phase brookite TiO₂ nanoparticles. PVP plays a stabilizing and dispersing role in the formation of brookite TiO₂ nanoparticles. With the increase of the dosage of PVP, the particle size of brookite TiO₂ samples decreases first and then increases, while the band gap value remains in the range of 3.2~3.3 eV. The optimal dosage of PVP is 0.2 g, and the obtained brookite TiO₂ nanoparticles under this condition show the smallest particle size (about 21.0 nm) and highest photocatalytic activity, that is, the degradation rate of MB solution reaches 96.4% after UV irradiation for 120 min.