Synthesis of Anatase Mesoporous TiO2 by Using Cyclodextrin as a Pore Forming Template via Hydrothermal Treatment

Abstract

Porous titanium dioxide with an average pore diameter of several nanometers and a narrow pore size distribution was prepared by using cyclodextrin (CD) in a sol-gel reaction of titanium precursor. After the reaction, a hydrothermal treatment was performed, and a WAXD analysis shows that the hydrothermal treatment successfully induces an anatase crystalline structure in TiO2. The combined results from TGA, FT-IR, N-2 adsorption-desorption isotherm, TEM, and SEM analyses show that the CD act as a pore forming template to form TiO2 with a wormhole-type pore and a large specific surface area. Furthermore, the ratio of the CD/Ti precursor affects the porosity and the morphology of the mesoporous TiO2. In contrast, TiO2 prepared without CD does not exhibit a porous structure. The formation of these porous structures is a result of the self-assembly of Ti species around the CD molecules, TiO2 growth, and pore-forming by the removal of CD.