Announcing the Final Examination of Yifei Fu for the degree of Doctor of Philosophy
Cerium oxide nanoparticles (CeNPs) are a significant class of nanomaterials known for their unique redox properties. Generally, the physical and chemical properties of nanomaterials are strongly affected by their sizes and morphology. To develop a well-controlled synthesis strategy, it is crucial to understand the kinetic and thermodynamic aspects of atomic or molecular assembly in the synthesis system.
In this dissertation, we aim to investigate the formation of CeNPs in solution through wet chemical synthesis by investigating the hydrolysis behavior of cerium ion precursor at various temperatures and different chemical environments. The beginning of this work provides an introduction and summary of some common concepts widely used in understanding the formation of nanoparticles. In chapters two and three, the spontaneous hydrolysis behavior of tetravalent cerium salts, Ce(IV), in aqueous systems was studied in detail to understand the influence of synthesis conditions on the nucleation kinetic and morphology evolution in the course of particle growth. Additionally, combined with computational simulation, we have investigated the impact of acetate molecules on the growth of CeNPs. These results have proven that the formation of surface carboxylic groups alters the preferred growth direction of CeNPs from (100) to (111). This change occurs because acetate ions exhibit a stronger interaction with the (100) surface compared to the (111) surface. Furthermore, in chapter four, we examine the impact of faceted CeNPs on biomolecule conjugation and their performance in gene delivery for the regulation of abnormal diabetic wound healing.
Overall, as cerium oxide has found widespread application in various fields, such as catalysis, chemical-mechanical polishing, solid fuel cell, and bioremediation, the results obtained from this dissertation not only provide valuable insights into the development of a precise and controlled strategy for nanoclusters and faceted nanoparticles synthesis, but also hold significant promise for enhancing the practical applications of cerium oxide nanoparticles.
Committee in Charge:
Sudipta Seal, Chair, Materials Science and Engineering
Jiyu Fang, University of Central Florida, Department of Materials Science and Engineering
Melanie Coathup, University of Central Florida, College of Medicine
Swaminathan Rajaraman, University of Central Florida, Department of Materials Science and Engineering
Yajie Dong, University of Central Florida, Department of Materials Science and Engineering