Publication

Abstract : Cadmium selenide (CdSe) quantum dots in selective size were prepared by using inverse micelle technique without the presence of trioctylphosphine (TOP) and characterized by UV-visible absorption, Fourier transform infrared (FTIR) and photoluminescence (PL) spectroscopic studies. The UV-visible absorption and PL studies showed strong quantum confinement effect and bandgap energy about 2.1eV in CdSe quantum dots. Particle size and electron diffraction analyses in high resolution transmission electron microscopy (HRTEM) confirmed the formation of CdSe crystalline particles in the range of 3.1-3.9nm. These wide bandgap CdSe quantum dots were used for the preparation of CdSe-TiO2 nanocomposites of TiO2 nanoparticles and TiO2 nanowires. HRTEM images of the CdSe-TiO2 nanowires (CdSe-TNW) and the CdSe-TiO2 nanoparticles (CdSe-TNP) composites revealed the uniform, layered distribution of CdSe quantum dots on TiO2 nanoparticles and on TiO2 nanowires in different dimensions. Further, the differences in the dimensional distributions and optical properties of CdSe-TNW and CdSe-TNP nanocomposites were investigated for their applications to TiO2 sensitized solar cells. © 2014 Elsevier Ltd.