ALKANE CHALCOGENOLATE - PROTECTED METAL NANOPARTICLES: SYNTHESIS, FORMATIONS, CHARACTERIZATIONS, AND INTERFACE INVESTIGATIONS
Organo selenolate - protected gold (Au) nanoparticles (NPs) have shown high potential for nanoelectronic applications, where electrochemical studies are crucial for understanding the charge transfer mechanism between the metal core and ligand, specifically the anchoring element (Se). Complete interfacial characterization of the NPs is essential prior to electrochemical studies to confirm uniform composition. This dissertation focuses on the successful synthesis of such homogenous NPs and interfacial characterizations between the Au core and the ligand.Previous mechanistic studies into the renowned Brust - Schiffrin method (BSM), i.e., one - and two - phase syntheses, performed on thiolate - stabilized Au NPs identified that NP homogeneity was dependent on the precursor species prior to the formation of NPs. The research herein produced a number of key findings: the effect of encapsulated water and the amount of phase-transfer agent in the two - phase BSM were significant factors for producing higher quality NPs when comparing dialkyl disulfides and dialkyl diselenides as ligands precursors; the one - phase BSM was found to be a better route than the two - phase BSM for the production of homogenous NPs, since it produced only one intermediary species. Moreover, the effects of the ligand and alkyl chain lengths with different chalcogen anchoring elements, i.e., S, Se, and Te, on the resultant NPs were characterized by a variety of analytical techniques.Additionally, the prospective utilization of alkyl selenocyanates as the ligand precursors for synthesis of alkane selenolate - protected Au NPs is demonstrated in this dissertation. Although the successful formation of Au NPs was achieved, the existence of cyano species on the surface of the metal core was experimentally challenging to determine.The main conclusions drawn from this research are the ability to synthesize homogenous alkane selenolate - protected Au NPs by having a deeper understanding of the chemical structures of the precursor species in the NPs synthesis. In brief summary, this research includes fundamental investigations on the interfacial behavior between the Au core and alkane selenolate ligand that are essential for electrochemical and charge transfer studies that further the potential for application in the nanoelectronics field.
Showing items related by title, author, creator and subject.
Mechanistic insight into the Brust-Schiffrin two-phase method for organochalcogenate-protected metal nanoparticles Li, Ying. (Georgetown University, 2011)
Synthesis and Characterizations of Gold Chalcogenolate-Protected Nanoclusters and Nonoparticles: Structural Analysis by 77SE and 125TE NMR XIE, YUANJIE (Georgetown University, 2015)The objective of this thesis is to study the synthesis and characterizations of gold nanoparticles (Au NPs) and nanoclusters (Au NCs) with different anchoring elements, S, Se, and Te. 77Se and 125Te both are nuclear magnetic ...
Synnott, Stephanee Lynn (Georgetown University, 2014)Three projects were explored for this dissertation 1) Metal Catalyzed Transfer Hydrogenation, 2) Non-Metal Catalyzed Transfer Hydrogenation and 3) On-Water Reactivity. For the first project, Noyori's Ru catalyst1, which ...