Controlled synthesis of nanostructures and their optical properties

Abstract

In light of the achievements in controlling the synthesis of single-material nanocrystals, research trend has clearly shifted towards studying multi-component nanocrystals that promised varied functionalities and scientific interests. The works covered in this thesis are in cognisant of the trend and are designed to help better understand the control and modification of the structural and optical properties of multi-component nanocrystals.

In the first part of the works, we successfully synthesized sandwich CdS|CdSe|CdS and CdSe|CdS|CdSe nanorods, followed by the deposition of gold nanoparticles onto these nanorods. The optical properties of each system were investigated. The second part documented a case study involving gold-deposited CdS/ZnS:Mn2+ doped-and-seeded heterostructured nanocrystals (HNCs) which involved the simultaneous presence of two potential quenchers (Au and Mn2+ dopants) of semiconductor band gap emissions on the same HNC system. It offered a systematic and stepwise modification of structural and optical properties of nanocrystals.