Control Growth And Properties Of Nanostructured Sulfide Semiconductors

Nanostructured Sulfide Semiconductors are very important wide-band-gap inorganic semiconductor materials. Therefore, much attention has been paid to the short-wave photoelectric semiconductor materials because of their excellent properties. Investigation on controlled growth of nanomaterials so as to realize the application tailored design and the synthesis of nanomaterials with specific morphologies and sizes is the tackling issue in the current research on nanomaterials. This present thesis aims to investigate in depth the growth mechanisms and the rules for the morphology evolution of applied sulfide semiconductor nanostructures; explore the novel physical properties correlated with novel structures. The research is mainly focused on controlled growth of nanomaterials, the growth dynamic rules and the correlation between morphology evolution and experimental parameters.The main contents and originality of the thesis are as follows:1. Controlled growth and property of typical Dilute Magnetic Semiconductor Manganic sulfide were researched. Many novel Manganic sulfide nanostuctures including flower-like ZnO, three-legged MnS, stick MnS and pyramid MnS has been successfully synthesized via solvothermal method. The effect of various experimental parameters including the sort of sulfide, the temperature at the reaction, reactive time, the ratio of reactant and the sort of solvent were studied on the properties. These nanostructures morphology growth processes and interactional evolution also have been studied. The growth mechanism of the MnS nanostructures is attributed to Ostwald ripening process. The optical properties of the products were also recorded by means of photoluminescence (PL) spectroscopy. Electron paramagnetic resonance measurement revealed the paramagnetic nature of the MnS crystals. That is significant for the investigation of novel physical properties originated from special structures. The optical properties and magnetic nature of the MnS nanoflower are the best than others.2. ZnS hollow microspheres were prepared via a facile template-free chemical vapor deposition (GVD) route. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometer (EDX). The optical properties of the products were also recorded by means of photoluminescence (PL) spectroscopy. The growth mechanism of the ZnS microstructures is attributed to Kirkendall process. The quantity of S is deemed as a critical parameter in modulating the shell thickness and PL intensity of ZnS microstructure. A higher S content increase the shell thickness, and cause the luminescence quenching. The growth mechanism of the ZnS microstructures is attributed to Kirkendall process. Hollow sphere structure was synthesized by a new template-free method.