SYNTHESIS AND OPTICAL PROPERTIES OF THIOGLYCOL-CAPPED CdSe QUANTUM DOTS EMBEDDED IN TiO2 FILMS FOR SOLAR CELL APPLICATIONS

CdSe quantum dots have been prepared via a colloidal route using Mercaptoethanol (Thioglycol) (HOCH2CH2SH) as a capping agent. The stability of the particles in solution and embedded in TiO2 matrices has been followed by optical absorption and photoluminescence. Both the size and the size distribution of the particles are well controlled by ratio mole and temperature, thus allowing a tunable emission. Room temperature photoluminescence (PL) studies are reported, the band is assigned to recombination through defect states, whose energy depends on the nanocrystallite size and so depend the optical band gap on the nanocrystallite. X-ray, UV-Vis spectroscopies, and TEM have been used to characterize colloidal CdSe. With CdSe nanoparticles as seeds on TiO2 film, a highly efficient of CdSe/TiO2 thin films photoanode was prepared by dip coating deposition technique.