Fabrication of TiO2 hollow microspheres and their applications

• Main Authors: Chih-Kuei Ke, 葛智逵
• Other Authors: Shu-Hua Chien
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/41834344692772579548

碩士 === 國立臺灣大學 === 化學研究所 === 99 === Titania hollow microspheres (THMS) were prepared by a two-step solvothermal process. The solid titania precursor was formed in a solution containing TiOSO4, ethanol, glycerol and ethyl ether at 110oC for 4 h in the first step. In the second solvothermal step, it was found that the morphological integrity of the hollow microspheres could be controlled by varying the concentration of ethanol. We obtained uniform THMS in pure anatase phase, with 1～2 μm diameter and 310 m2/g of surface area. All the samples were characterized by XRD, UV-Vis, N2 sorption isotherms, FESEM and HRTEM. In the present study, we have applied the prepared THMS to use in dye sensitized solar cells(DSSCs) and solar water splitting. In DSSCs, the THMS was used as a scattering layer atop the conventional TiO2 nanoparticle film. The solar energy conversion efficiency was significantly enhanced by nearly 15% as compared to that without THMS layer sensitized with N719 dye under AM 1.5 solar irradiation (100 mW/cm2). The improved light harvesting characteristics were due to dye adsorption capacity of the THMS and its high diffusion reflectance property which attest to the superior light scattering property. In the solar photoelectrocatalytic water splitting, considerably high photoconversion efficiencies of 3.86% was attained by the CdS quantum dots sensitized THMS and of 4.55% was reached by the CdSe quantum dots sensitized THMS that were prepared by SILAR process. By CdS and CdSe cosensitization of THMS, the highest efficiency of 5.13% was achieved. Accordingly, the titania hollow microspheres can be beneficial for application in solar energy conversion.