Abstract
Europium doped Bi4Ge3O12 nanocrystals were successfully obtained by solid state reaction between precursor oxides at 800 oC. The XRD and XPS measurements shows an increasing of the lattice constant in the case of Eu:BGO nanocrystals, due to the electropositive character of Eu(III) ions compared with the host cations, which induces an ionic character for Eu-O bound and a more covalent one for the Ge-O bounds. The photoluminescence of Eu:BGO due to 5D0ā 7F2 transition have a lower splitting compared with Eu:BGO monocrystals suggesting a lower crystal field in the sintered nanocrystals, due to a mixing between the crystalline and amorphous phases.
Keywords
Powders-solid state reaction, Grain size, Spectroscopy, Mixing.
Citation
S. POLOSAN, E. MATEI, C. LOGOFATU, Synthesis of Eu-doped bismuth germanate nano-ceramic powder, Optoelectronics and Advanced Materials - Rapid Communications, 4, 10, October 2010, pp.1503-1508 (2010).
Submitted at: July 24, 2010
Accepted at: Oct. 14, 2010