(Invited) Synthesis Design Strategies of Faceted Cerium Oxide Nanoparticles and its Properties

Abstract

Cerium oxide nanoparticles (CNP or nano-ceria) are widely studied for their use in catalysis, energy, environmental protection, and bio-medical applications. Recently CNP is used as additives for Chemical Mechanical Planarization (CMP) slurries. The chemical performance of ceria in many of these applications depends on the ability of cerium to switch between +3 and +4 oxidation states. Our research involves examination of the synthesis design strategies of CNP with various shape and sizes and their effect on the surface chemistry. In most catalytic applications, highly reduced ceria surfaces play an active role and very similar observation is also noted in increased CMP removal rates. While high resolution TEM (HRTEM) is used to follow the particle morphology evolution, the surface effects are studied using high resolution X-ray photoelectron spectroscopy (XPS) of the Ce 3d spectrum. Atomistic computer simulations were used to help rationalize how the synthetic conditions impact upon the morphology of the nanomaterial. Further we provide understanding of the adsorption Interface of Polyelectrolyte Coating on Redox Active CNP Using Soft Particle Electro kinetics, which is relevant to CMP and biomedical applications. This talk summarizes some of our observations of the impact that synthesis route, storage and environmental conditions have on the properties of CNPs.