The stark effects on group II-VI semiconductor nanoparticles (NP) during synthesis in solution and on NP embedded in a glass matrix and in nanostructructed thin films

The main purpose in the thesis is to change the dimensions of the various compositions of quantum dots and investigate their optical and electro-optical properties. This investigation was divided into three main parts: 1) preliminary studies starting with thin films, preparation of the sample and design set up, taking of absorption spectra measurement. Changes in optical absorption and electro-absorption properties were observed in multilayer of CdTe nanoparticles thin film especially when the amount of sample, annealing time, temperature and coating method (layer by layer technique with spincoater) were changed. 2) The preparation of CdTe nanoparticles embedded in glass matrix sandwiched between ITO glasses was also investigated depending on the heat treatment time and temperature to control the size and to optimize the optical and electro-optical properties of the nanoparticles. 3)Synthesis and characterization water soluable CdTe quantum dots with different size. Mercaptopropionic acid was used as an capping agent which is important for reducing toxidity and controlling the size of the nanoparticles. UV-Vis absorption, electro-absorption and raman spectra were carried out to characterize the optical properties of these nanoparticles. Investigations and development were made during the synthesis and production by varying the heat-treatment time, temperature, pH of the solution and capping agent. Effects of electro modulation on the nanoparticles nano structured thin films, glass matrix and solution were studied and the results analysed with spectroscopic techniques.