Laser-Induced Anatase-to-Rutile Transition in TiO2 Nanoparticles: Promotion and Inhibition Effects by Fe and Al Doping and Achievement of Micropatterning

摘要

A study of the anatase to rutile transition (ART) induced by laser irradiation in TiO2 nanoparticles synthesized by a modified Pechini method has been carried out in this work, with special attention focused on the effects of doping with Al or Fe on the phase transition. Either promotion or inhibition of ART can be achieved by Fe or Al doping, respectively, as demonstrated by X-ray diffraction, Raman spectroscopy, photoluminescence, X-ray absorption, and transmission,electron microscopy results presented in this work. The influence of dopants (Al, Fe) in the kinetics of the ART, the key role played in this process by the surface of the nanoparticles and the presence of oxygen vacancies, and the formation of rutile nucleation points at twinned regions have been discussed in this work. Finally, advantage has been taken of the ART controlled by laser irradiation, and an original laser-induced micropatterning based on spatial phase-controlled titania polymorphs has been developed, which assures significant progress in challenging microdevice design based on titania polymorphs.