SYNTHESIS OF MESOPOROUS NANOCRYSTALLINE TIO_2 WITH POTATO STARCH ASPORE TEMPLATE AND ITS PHOTOCATALYTIC ACTIVITY

摘要

High porosity of nanocrystalline TiO_2 on mesoporous scale has been synthesized through sol-gel process by using potato starch as pore forming agent. The gel starch template was immersed for 4 days in the colloidal of TiO_2 nanoparticles which were prepared by hydrolyzing titanium (IV) tetraisopropoxide (TTIP) in ethanol at pH 1 for 24 hours. Mesoporous TiO_2 was obtained by template removing through combination of etanol-HCI extraction and calcination at 500°C for 4h. XRD diffractogram reveals nanocrystalline anatase phase of TiO_2 with particle size up to 12.96 nm. The N_2 adsorption-desorption isotherm shows mesoporosity of TiO_2 powder with specific surface area up to 65.65 m~2/g. As the powders were intended to be used as dye substrate for dye-sensitized solar cells, the photocatalytic activity over I_3 formation has been evaluated at 288 nm of UV region. It is resulted that potato starch templated-TiO_2 shows higher activity than those of Degussa P25 and nontemplated-Ti0_2.