Crystal and defect structures of La2/3 xLi3xTiO3 (x ~ 0.1) produced by a melt process.
The crystal and defect structures of coarse-grained crystals of La(2/3-x)Li(3x)TiO3 grown from the melt by the Tammann-Stöber method were studied by transmission electron microscopy and powder X-ray diffraction. The as-grown crystals of La(2/3-x)Li(3x)TiO3 have a Li-poor composition of La(0.57)Li(0.29)TiO3 and a diagonal-type unit cell of 2(1/2)a(p) x 2(1/2)a(p) x 2a(p) with the tetragonal symmetry [space group: P4/nbm (#125)] due to both the La-cation ordering and the tilting of TiO6 octahedra. The secondary La2Ti2O7 phase precipitates in the form of plates in the La(2/3-x)Li(3x)TiO3 phase with the orientation relationships of 001(p)//[100](La2Ti2O7) and {110}(p)//(001)(La2Ti2O7), which may cause detrimental effects to ionic conductivity.
Department of Materials Science and Engineering, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan. k.kishida@materials.mbox.media.kyoto-u.ac.jp
Kyosuke
K
Kishida
Mai
M
Miyata
Naoyuki
N
Wada
Norihiko L
NL
Okamoto
Katsushi
K
Tanaka
Haruyuki
H
Inui
Hiroshi
H
Koyama
Takeshi
T
Hattori
Yasutoshi
Y
Iriyama
Zempachi
Z
Ogumi
D003460:Crystallization; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D018020:Lithium Compounds / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission / Q000379:methods*; D014961:X-Ray Diffraction
D028581:Lanthanoid Series Elements; D018020:Lithium Compounds