title: Influence of Aging and Environment on Nanoparticle Chemistry - Implication to Confinement Effects in Nanoceria.
abstract: The oxidation state switching of cerium in cerium oxide nanoparticles is studied in detail. The influence of synthesis medium, aging time and local environment on the oxidation state switching, between +3 and + 4, is analyzed by tracking the absorption edge using UV-Visible spectroscopy. It is observed that by tuning the local environment, the chemistry of the nanoparticles could be altered. These time dependent, environmentally induced changes likely contribute to inconsistencies in the literature regarding quantum-confinement effects for ceria nanoparticles. The results in this article indicate that there is a need to carry out comprehensive analysis of nanoparticles while considering the influence of synthesis and processing conditions, aging time and local environment.
authors.affiliation: Advanced Materials Processing and Analysis Center, Mechanical, Materials Aerospace Eng, University of Central Florida, Orlando, FL-32816, USA ; EMSL, Pacific Northwest National Laboratory, Richland, WA-99354, USA ; Battelle Science and Technology India, Pune, MH-411057, India.
authors.forename: Satyanarayana Vnt
authors.initials: SV
authors.lastname: Kuchibhatla
authors.forename: A S
authors.initials: AS
authors.lastname: Karakoti
authors.forename: D R
authors.initials: DR
authors.lastname: Baer
authors.forename: S
authors.initials: S
authors.lastname: Samudrala
authors.forename: M H
authors.initials: MH
authors.lastname: Engelhard
authors.forename: J E
authors.initials: JE
authors.lastname: Amonette
authors.forename: S
authors.initials: S
authors.lastname: Thevuthasan
authors.forename: S
authors.initials: S
authors.lastname: Seal