Nanocrystalline (NC) semiconductor quantum dots (QD) are important building blocks of nanotechnology. They are promising for optoelectronic applications due to fascinating properties e.g easy solution processibility, narrow emission linewidth and high absorption coefficient. In particular their applications in the areas of photodetectors and photovoltaics have attracted the attention of the research community.

In this dissertation an extensive study of the charge transport in II-VI semiconducting QDs and its composites with conductive polymers is performed. The transport properties are investigated using optical and electrical measurements. Different fabrication techniques are used to enhance the interdot tunneling currents in the QD networks. Annealing of QDs has been observed to be a promising technique for enhancing photoresponse. Negative differential resistance phenomenon is observed in the nanocomposites of QDs with the polymers with high peak to valley ratios of current at room temperature. The charge transport is modeled using single particle approach (using a transfer matrix formulation) and many body coherent electron transport models. Carrier relaxation is investigated with time resolved optical spectroscopy. Different phonon modes are observed experimentally in the NC QDs using Raman scattering techniques. The phonon modes are computed using a dielectric continuum model and the correlation of electron phonon scattering rates on the QD sizes is studied.