Investigations into the Properties of CdSe-Based Nanocrystals via Manipulation of the Size, Shape, and Surface Chemistry
Cadmium selenide (CdSe)-based nanocrystals are widely studied because of their versatile and simple syntheses and their excellent and tunable optoelectronic properties. This leads to their use in a wide variety of optical and photonic applications including solar cells, displays, and biofluorescent imaging. Optoelectronic devices such as solar cells or luminescent solar concentrators offer a vast potential for harvesting renewable energy, however the efficiency, reliability, and cost of these devices need to be improved for large-scale implementation. While much of the research on incorporating chalcogenide-based nanocrystals into solar devices has focused on spherical quantum dots, anisotropic materials can offer properties, such as polarized emission, which aren’t achievable with 0D particles. To fully realize the potential of incorporating these NCs into devices such as luminescent solar concentrators, further studies are needed. This thesis aims to cover a range of questions, including how the composition, size, shape, and surface chemistry of the CdSe-based NCs affect their properties. We discuss the various synthesis routes currently used and the properties arising from the highly-crystalline, monodisperse particles achieved. We then focus further on dot-in-rods, showing how their shape and size influence the photoinduced electron-hole separation and recombination as well as unique properties arising from the anisotropic shape. A novel nanocrystal morphology, who’s unique shape and large absorption cross-section provide the potential for photocatalytic applications, is presented and the mechanisms of formation are explored. Lastly, the optical and electrochemical effect of binding electrochemically active ferrocene ligands to the NC surface to replace the inherently insulating ligands is presented, along with first spectroelectrochemical studies of these organic-inorganic hybrids. These studies aim to elucidate the charge transfer process occurring between the ferrocene groups and the QDs via direct correlation of the applied potential to the absorption.
Gogotsi, Natalie, "Investigations into the Properties of CdSe-Based Nanocrystals via Manipulation of the Size, Shape, and Surface Chemistry" (2020). Dissertations available from ProQuest. AAI27960972.