Light element analysis in oxycarbonate superconductors using EELS.
Elemental analysis in an oxycarbonate superconductor ((Cu,N,C)Sr2CaCu2Oy) is conducted using transmission electron microscope-electron energy-loss spectroscopy with detector-gain correction. The gain correction enables highly sensitive elemental analysis and precise measurement of energy-loss near edge structures (ELNESs). It is found that carbon is included as a CO3 group, because the carbon K-edge in the oxycarbonate shows the same ELNES observed from CaCO3. Nitrogen ELNES is similar to that of Sr(NO3)2, so nitrogen is contained as a NO3 group. Although both CO3(2-) and NO3- have similar planar atomic arrangements, the nitrogen ELNES observed is different from that of carbon. EEL spectrum simulation based on DV-Xalpha method is used to interpret the difference.
Kimoto
K
K
Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Ibaraki, Japan. KIMOTO.Koji@nims.go.jp
Anan
Y
Y
Asaka
T
T
Zhigadlo
N D
ND
Muromachi
E
E
Matsui
Y
Y