以异丙醇钛(C12H28O4Ti)为主要原料合成氧化钛(TiO2)前驱体溶胶,并结合230℃水热处理得到TiO2溶胶,利用电流体动力学(EHD)技术在掺氟氧化锡导电(FTO)玻璃基片上镀膜,450℃高温煅烧制备具有多级结构锐钛矿TiO2纳米薄膜。以硝酸镉(Cd(NO3)2)及硫化钠(Na2S)分别为镉源和硫源,采用化学浴沉积技术在TiO2薄膜上沉积制备了量子点敏化的异质薄膜。采用X射线衍射(XRD)、电子扫描电镜(SEM)、电子透射电镜(TEM)以及紫外-可见吸收光谱(UV-Vis absorbance spectra)对薄膜结构和性能进行表征。结果表明,纳米TiO2薄膜具有亚微米球簇堆积结构,球簇之间形成尺寸连续分布的微纳通道,便于溶液的浸润和离子的表面吸附。敏化制备异质薄膜中硫化镉以量子点状态存在,晶粒尺寸为3~5nm范围内。UV-Vis吸收光谱证实量子点的量子限域效应,吸收发生蓝移现象。
Nanocrystalline TiO2 solution was prepared by hydro-thermal treatment at 230℃ with titanium(Ⅳ) isopropoxide (C12H28O4Ti) as precursor solution. Anatase TiO2 nanocrystalline films with hierarchical structure were prepared on FTO glass substrates by electrohydrodynamic (EHD) technique and sintered at 450℃. CdS quantum dot sensitized nanocrystalline TiO2 heterostructure films were deposited by chemical bath method using the Cd(NO3)2 solution and Na2S solution as the reactants. The crystal structure, morphology and optical property of the film were investigated. The results indicate that nanocrystalline TiO2 films stack with the submicron spherical clusters, submicron and nanometer channels with wide dimension formed among the clusters which can facilitate the solution facilitation and ions adsorption. Nanocrystalline TiO2 heterostructure films exist with CdS quantum dots with the range of 3-5nm. UV-vis Absorbance spectra verified the blue shift of heterostructure films due to the quantum confinement effects of quantum dots.