title: Sonochemical synthesis of cerium oxide nanoparticles-effect of additives and quantum size effect.
abstract: Cerium oxide (CeO(2)) nanoparticles were prepared sonochemically, by using cerium nitrate and azodicarbonamide as starting materials, and ethylenediamine or tetraalkylammonium hydroxide as additives. The additives have a strong effect on the particle size and particle size distribution. CeO(2) nanoparticles with small particle size and narrow particle size distribution are obtained with the addition of additives; while highly agglomerated CeO(2) nanoparticles are obtained in the absence of additives. Monodispersed CeO(2) nanoparticles with a mean particle size of ca. 3.3 nm are obtained when tetramethylammonium hydroxide (TMAOH) is used as the additive and the molar ratio of cerium nitrate/azodicarbonamine/TMAOH is 1/1/1. Blue shifts of the absorption peak and the absorption edges of the products are observed in the UV-Vis absorption spectra as a result of the quantum size effect. The samples have been characterized using powder XRD, TEM, DLS, and absorption spectra.
authors.affiliation: Department of Chemistry, Bar-Ilan University, Ramat-Gan 52900, Israel.
authors.forename: Lunxiang
authors.initials: L
authors.lastname: Yin
authors.forename: Yanqin
authors.initials: Y
authors.lastname: Wang
authors.forename: Guangsheng
authors.initials: G
authors.lastname: Pang
authors.forename: Yuri
authors.initials: Y
authors.lastname: Koltypin
authors.forename: Aharon
authors.initials: A
authors.lastname: Gedanken