Silicon-Doped LiFePO4 Single Crystals: Growth, Conductivity Behavior, and Diffusivity

被引：66

作者：

Amin, Ruhul ^{[1
]}

Lin, Chengtian ^{[1
]}

Peng, Jubo ^{[1
]}

Weichert, Katja ^{[1
]}

Acartuerk, Tolga ^{[1
]}

Starke, Ulrich ^{[1
]}

Maier, Joachim ^{[1
]}

机构：

[1] Max Planck Inst Solid State Res, D-70569 Stuttgart, Germany

来源：

ADVANCED FUNCTIONAL MATERIALS | 2009年 / 19卷 / 11期

关键词：

CHEMICAL DIFFUSION; TRANSPORT; LITHIUM; PERFORMANCE; EXISTENCE;

D O I：

10.1002/adfm.200801604

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Single crystals of silicon doped LiFePO4 with a silicon content of 1% are grown successfully by the floating zone technique and charcterized by single- crystal and powder X-ray diffraction secondary ion mass spectroscopy, and chemical analysis. Electron paramagnetic resonance demonstrates the presence of only Fe2+; no traces of Fe3+ are found. Impedance spectroscopy as well as step-function polarization/depolarization (DC) measurements are carried out using the cells Ti/LiFe(Si)PO4/Ti and LiAl/Lil/LiFe(Si)PO4/ Lil/LiAl. The electronic and ionic conductivites as well as the Li-diffusivity of the sample in the mayor crystallographic directions ([h00], [0k0], and [001]) are determined. Within experimental error the transport properties along the b- and c-axes are found to be the same but differ significantly from the a-axis, which exhibits lower values. Compared to undoped LiFePO4, Si-doping leads to an increase of the ionic conductivity while the electronic conductivity decreases, which is in agreement with a donor effect. The activation energies of conductivites and diffusivities are interpreted in terms of defect chemistry and relevant Brouwer diagrams are given.

引用

页码：1697 / 1704

页数：8

共 30 条

[1] Ionic and electronic transport in single crystalline LiFePO4 grown by optical floating zone technique [J].

Amin, R. ;

Maier, J. ;

Balaya, P. ;

Chen, D. P. ;

Lin, C. T. .

SOLID STATE IONICS, 2008, 179 (27-32) :1683-1687

[2] Effect of annealing on transport properties of LiFePO4:: Towards a defect chemical model [J].

Amin, R. ;

Maier, J. .

SOLID STATE IONICS, 2008, 178 (35-36) :1831-1836

[3]

Amin R, 2008, PHYS CHEM CHEM PHYS, V10, P3524, DOI 10.1039/b801795f

[4] Aluminium-doped LiFePO4 single crystals [J].

Amin, Ruhul ;

Lin, Chengtian ;

Maier, Joachim .

PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 2008, 10 (24) :3519-3523

[5] Anisotropy of electronic and ionic transport in LiFePO4 single crystals [J].

Amin, Ruhul ;

Balaya, Palani ;

Maier, Joachim .

ELECTROCHEMICAL AND SOLID STATE LETTERS, 2007, 10 (01) :A13-A16

[6]

[Anonymous], P 7 M INT COMM EL TH

[7]

[Anonymous], 2004, Physical Chemistry of Ionic Materials

[8]

Arroyo-de Dompablo M. E., 2006, SOLID STATE IONICS, V177, P2625

[9] Floating zone growth of lithium iron (II) phosphate single crystals [J].

Chen, DP ;

Maljuk, A ;

Lin, CT .

JOURNAL OF CRYSTAL GROWTH, 2005, 284 (1-2) :86-90

[10]

CHUNG SY, 2003, ELECTROCHEM SOLID A, V278, P6

← 1 2 3 →