R. Jiang, H.-Y. Zhu, H.-H. Chen, J. Yao, Y.-Q.
Fu, Z.-Y. Zhang, Y.-M. Xu. Effect of
calcination temperature on physical parameters and photocatalytic activity of mesoporous titania spheres using chitosan/poly(vinyl alcohol) hydrogel beads as a template. Applied Surface Science. Accepted.
Abstract: Mesoporous titania spheres were prepared by modi?ed
sol–gel method using chitosan/poly(vinyl alcohol) hydrogel beads as a template. Effects of calcination temperature on physical parameters
were investigated by X-ray diffraction (XRD), N2 adsorption-desorption,
Fourier transform infrared (FT-IR) spectra, thermogravimetry and differential
thermal analyses (TG-DTA), high-resolution transmission electron microscope
(HRTEM) and scanning electron microscopy (SEM). The photocatalytic
activity of mesoporous titania spheres prepared was also evaluated by
photocatalytic degradation of phenol as a model molecule under UV irradiation. With increasing calcination temperature, average crystallite size and pore size
increased. In contrast, Brunauer-Emmett-Teller (BET) specific
surface areas, porosity and pore volumes steadily decreased. Results of
characterization proved that prepared titania spheres with highly organized
pores were mesoporous structure. The photocatalytic activity of mesoporous
titania spheres calcined at 500°C was more effective than those calcined at
other temperatures, which were attributed to the porous structure, large BET
surface area, crystalline, and smaller crystallite size. This work may provide new insights into the preparation of novel mesoporous
titania spheres and further practical applications in the treatment of
wastewater.