Synthesis of nanocrystalline TiO2 by a salt-leaching assisted sol-gel method and their photoelectrochemical properties.
Porosity-controllable TiO2 nanocrystallines with pure anatase phase have been synthesized through a salt-leaching assisted sol-gel method, where glycerol was used as the dispersant to disperse the inorganic precursor (tetrabutyl titanate, TBT) and the chelating ligand to attenuate the hydrolysis/condensation reaction kinetics, while the salts (NaCI) were used as porosity-induced agents to produce pores in the final titania products when the salts leached out. The porosities and surface areas of obtained titania samples could be adjusted by altering the NaCI concentration in the precursor sol, which was examined by experimental techniques such as XRD, TEM and Brunauer-Emmett-Teller (BET) nitrogen adsorption-desorption. In addition, their photocurrent actions and photocatalytic abilities were also investigated so as to address the relationship between the nanostructures and their photoelectrochemical properties. It was demonstrated that the obtained titania samples exhibited different photocurrent actions and photocatalytic activities due to their different morphologies, particle sizes, surface areas as well as pore architectures. Therefore, the salt-leaching assisted sol-gel method described herein offers a new effective and facile strategy for the preparation of pure anatase TiO2 nanocrystallines with adjustable porosity, as well as provides the titania products with specific photoelectrochemical properties for applications in a variety of areas such as photovoltaic cells, photocatalysis and so on.
Department of Chemistry, University of Science and Technology of China, Hefei 230026, China.
Da
D
Chen
Geng
G
Wang
Hao
H
Zhang
Jinghong
J
Li