Study on Sol-hydrothermal Synthesis of TiO_2 Nanoparticles and their Photoelectric Properties Sensitized by Dye

TiO2 nanopaticle was synthesised by sol-hydrothermal using titanium isopropoxide as the precursor.The effects of synthesis conditions on grain size,crystallinity and phase transformation between phase-pure rutile and phase-pure anatase,were analyzed by TEM and XRD.It was revealed that crystal-type,crystallinity and crystal-size(from 10-20nm to 120nm) of TiO2 nanoparticles could be controlled by the pre-thermal treatment,hydrothermal temperature and concentration of the precursor.A paste,made from the nanoparticles and water,and by a doctor-blade technology which could control the thickness of the film were utilized to make a Dye-Sensitized Solar Cell(DSSC),which achieved a photoelectric conversion efficiency of 7.33%,as a result of the phase-pure anatase,appropriate grain size and favorable crystallinity of the TiO2 nanoparticles.It exceeded those DSSC's efficiencies made from the commercial paste or P25 paste.