Time-dependent Digestive Ripening of Colloidal Gold Nanoparticles Using Thiols and AminesLe, Vy Gold nanoparticleChemistryRipeningTimeLigand RatioChemistryB SGold nanoparticles have great potential for medicine, catalysis, and optics due to their surface chemistry and quantized energy gaps. However, there lacks total, atomistic control over the size and shape of these nanoparticles. To increase the versatility of these nanoparticles, researchers continue to investigate factors that can impact their growth. This study focuses on determining the effects of modifying the ratio of dodecanethiol, octanethiol, and oleylamine with the amount of gold over extended periods of time in comparison with the Brust-Schiffrin synthesis. UV-Vis spectroscopy, XPS, 1H-NMR spectroscopy, and TEM were used to analyze both the size and composition of these nanoparticles. Results indicate that an increased ligand to gold ratio continued to slightly decrease the size of the gold nanoparticle, likely due to thermodynamic stabilization. However, molar ratios less than 2:1 thiol to gold generated triangular, hexagonal, and even rectangular crystals, likely due to a lack of thiols on specific surfaces to allow more kinetically favored gold crystal growth in exposed areas. Systems with oleylamine created large, polydisperse nanoparticles no matter what, indicating the limited viability of amines as a ligand for gold. These synergistic insights on the growth of nanoparticles can help manipulate crystal growth in future studies and applications.Benjamin James Lear, Thesis SupervisorDavid D Boehr, Thesis Honors AdvisorRaymond Edward Schaak, Faculty Readeropen_access2025-04-02T03:03:50Zhttps://honors.libraries.psu.edu/catalog/9573vvl5147