Funct. Mater. 2014; 21 (2): 152-157.
Role of shallow electronic traps formed by oxygen vacancies in formation of luminescent properties of CeO2-x nanocrystals
Institute for Scintillation Materials, STC "Institute for Single Crystals", National Academy of Sciences of Ukraine, 60 Lenin Ave., 61001 Kharkiv, Ukraine
In the paper methods of thermoluminescence (TSL) and time-resolved spectroscopy were used for investigation of shallow electron traps near edge of 4f0 band in CeO2 and nonstoichiometric CeO2-x nanocrystals. It was shown that presence of the electronic traps located about 0.2 eV lower than the bottom of 4f0 band leads to sufficient modification of O2p-Ce4f excitation relaxation processes due to excitation retrapping. Strong dependence of TSL signal on the stoichiometry of nanocrystal allows to suppose that electronic defects are associated with oxygen vacancies and are formed by F+ centers.
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