Open AccessLocal structures around Co and Mn ions in ZnO‐based varistors
Author(s) -
Moriga T.,
Nakabayashi I.
Publication year - 1999
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s090904959801601x
Subject(s) - varistor , ion , manganese , materials science , phosphor , zinc , optoelectronics , engineering physics , chemistry , physics , metallurgy , organic chemistry , quantum mechanics , voltage
Local structures around Co and Mn ions in ZnO:M L, Co, Mn ( ML=Bi and La ) varistors were analyzed by fluorescent XAFS. It was found that Co ions are occluded in the ZnO matrix, taking a divalent state. As for Mn ions, they considered to take a trivalent state and a 6-fold coordination in the Bi-system. In the La-system, they would exist as a form of LaMnO3. x and the Mn-O distances varied with the content of Mn 4+ ions. We could estimate the content of Mn 4+ ion in LaMnO3+ x from the distances obtained, and about 35% Mn 4÷ ions may exist in the as-fired ZnO:La, Co, Mn varistor.