Architectural control of metal sulfide nanocrystals and polymer composites

Abstract

New methods for the preparation metal sulfide nanocrystals of different sizes, new shapes and novel compositions (polymer nanocomposites) were explored. In addition, the key elements in the mechanism by which the size and shape of the nanocrystals can be easily varied were investigated. Monodispersed Ag2S, CuxS and CdS nanocrystals were prepared from their corresponding molecular precursors. It was observed that the reactivity of the precursor played a crucial role in controlling the size, shape and crystalline phase of the nanocrystals. Hence, with the tailoring of the precursor's reactivity, together with some carefully controlled parameters, a series of well-defined metal sulfide nanocrystals with different dimensions and morphologies may be obtained. Through a series of controlled experiments and DFT calculations, underlying factors that determine the morphology and crystalline phase of the nanocrystals were unveiled.