abstract
A new solvent-exchange technique to prepare anatase nanoparticles with exceptional thermal stability and photocatalytic activity is described here. The process of preparation is accomplished by using organic solvents to precipitate hydrous titania particles from a basic aqueous medium containing a titanium peroxo complex. Undoped titanium dioxide formed via a solvent exchange method has unprecedented thermal stability against transformation to the rutile phase, as opposed to TiO2 prepared by the common method of the gelation of an aqueous titanium peroxo complex. On the basis of X-ray thermodiffraction experiments, it has been established that the thermal treatment at 1000 degrees C of the titania prepared by ethanol precipitation contains 100% pure anatase phase. The stabilization of anatase is induced by the high defectiveness of the TiO2 nanostructure, which is evidenced from band-gap energy estimation, PXRD and HRTEM studies. The prepared TiO2 nanoparticles show an outstanding photocatalytic activity comparable to the commercial Aeroxide P25 photocatalyst in the UV-assisted decomposition of methylene blue.
keywords
TITANIUM-DIOXIDE NANOMATERIALS; PHASE-STABILITY; NANOPARTICLES; RUTILE; SOL; TRANSFORMATION; NANOCRYSTALS; FEATURES; OXIDES; FILMS
subject category
Chemistry
authors
Krivtsov, I; Ilkaeva, M; Avdin, V; Amghouz, Z; Khainakov, SA; Garcia, JR; Diaz, E; Ordonez, S
our authors
Marina Ilkaeva
Junior Researcheracknowledgements
We gratefully acknowledge financial support from the Spanish MINECO (MAT2013-40950-R, CTQ2011-29272-C04-02, and Tecnicos de Infraestructuras Cientifico-Tecnologicas grants PTA2011-4903-I to Z.A. and PTA2011-4950-I to S.A.K.), the Government of the Principality of Asturias (Severo Ochoa PhD grant BP-14-029 to M.I.) and FEDER. South Ural State University acknowledges financial support of The Ministry of Education and Science of the Russian Federation Grant no. 16.2674.2014/K.