Sodium ion mobility in Na(x)CoO2 (0.6 < x < 0.75) cobaltites studied by 23Na MAS NMR.
Various P2 and P'3-Na(x)CoO(2) phases, with x ranging approximately from 0.6 to 0.75, have been studied by variable-temperature (23)Na magic angle spinning (MAS) NMR. Signal modification versus temperature plots clearly show that Na(+) ions are not totally mobile at room temperature on the NMR time scale. As the temperature increases, the line shape change of the (23)Na MAS NMR signal differs for the P2 and P'3 stackings and is interpreted by the differences of Na(+) ion sites and of sodium diffusion pathways in the two structures.
Carlier
Dany
D
ICMCB, CNRS Universite Bordeaux 1, 87 Av. du Dr. A. Schweitzer, 33608 Pessac Cedex, France. carlier@icmcb-bordeaux.cnrs.fr
Blangero
Maxime
M
Ménétrier
Michel
M
Pollet
Michaël
M
Doumerc
Jean-Pierre
JP
Delmas
Claude
C