Oxidation States of Mn Atoms at Clean and Al2O3-Covered LiMn2O4(001) Surfaces

被引：74

作者：

Ouyang, C. Y. ^{[1
,2
]}

Zeng, X. M. ^{[1
]}

Sljivancanin, Z. ^{[2
]}

Baldereschi, A. ^{[2
]}

机构：

[1] Jiangxi Normal Univ, Dept Phys, Nanchang 330022, Peoples R China

[2] PHB Ecublens, Inst Romand Rech Numer Phys Mat, CH-1015 Lausanne, Switzerland

来源：

JOURNAL OF PHYSICAL CHEMISTRY C | 2010年 / 114卷 / 10期

基金：

瑞士国家科学基金会; 美国国家科学基金会;

关键词：

INITIO MOLECULAR-DYNAMICS; SPINEL ELECTRODES; LITHIUM; STABILITY; LIXMN2O4; SYSTEMS;

D O I：

10.1021/jp911746g

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The electronic Structures of bulk and (001) Surfaces of lambda-MnO2 and LiMn2O4 have been Studied with density functional theory. In lambda-MnO2 the Mn oxidation state is +4 both in the bulk and at the (001) surface. In LiMn2O4, however, Mn atoms exhibit mixed Mn3+/Mn4+ oxidation states in the bulk, while Only Mn3+ at the (001) Surface, due to lower coordination with 0 atoms. The technically undesired Mn3+ ions form Lit LixN4Mn2O4 (001) even for very small Li concentrations. Upon covering the LiMn2O4 (001) Surface with Al2O3, the oxidation state Of Surface Mn atoms changes from +3 to +4, which explains the improved performance of coated LiMn2O4 cathodes in Li-ion batteries.

引用

页码：4756 / 4759

页数：4

共 29 条

[1] DENSITY-FUNCTIONAL THEORY AND NIO PHOTOEMISSION SPECTRA [J].

ANISIMOV, VI ;

SOLOVYEV, IV ;

KOROTIN, MA ;

CZYZYK, MT ;

SAWATZKY, GA .

PHYSICAL REVIEW B, 1993, 48 (23) :16929-16934

[2] First-principles calculations of the electronic structure and spectra of strongly correlated systems: The LDA+U method [J].

Anisimov, VI ;

Aryasetiawan, F ;

Lichtenstein, AI .

JOURNAL OF PHYSICS-CONDENSED MATTER, 1997, 9 (04) :767-808

[3] Ab initio study of the structural, electronic, and magnetic properties of MnO(100) and MnO(110) [J].

Bayer, V. ;

Franchini, C. ;

Podloucky, R. .

PHYSICAL REVIEW B, 2007, 75 (03)

[4] Comparison of metal ion dissolutions from lithium ion battery cathodes [J].

Choi, W. ;

Manthiram, A. .

JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 2006, 153 (09) :A1760-A1764

[5] Surface structure of LiMn2O4 electrodes [J].

Eriksson, T ;

Gustafsson, T ;

Thomas, JO .

ELECTROCHEMICAL AND SOLID STATE LETTERS, 2002, 5 (02) :A35-A38

[6] Improving the high-temperature performance of LiMn2O4 spinel electrodes by coating the active mass with MgO via a sonochemical method [J].

Gnanaraj, JS ;

Pol, VG ;

Gedanken, A ;

Aurbach, D .

ELECTROCHEMISTRY COMMUNICATIONS, 2003, 5 (11) :940-945

[7] DESIGN CONSIDERATIONS [J].

GOODENOUGH, JB .

SOLID STATE IONICS, 1994, 69 (3-4) :184-198

[8] Electronic structure, magnetic, and cohesive properties of LixMn2O4:: Theory -: art. no. 174408 [J].

Grechnev, GE ;

Ahuja, R ;

Johansson, B ;

Eriksson, O .

PHYSICAL REVIEW B, 2002, 65 (17) :1-7

[9] IMPROVED CAPACITY RETENTION IN RECHARGEABLE 4V LITHIUM LITHIUM MANGANESE OXIDE (SPINEL) CELLS [J].

GUMMOW, RJ ;

DEKOCK, A ;

THACKERAY, MM .

SOLID STATE IONICS, 1994, 69 (01) :59-67

[10] Surface/Chemically modified LiMn2O4 cathodes for lithium-ion batteries [J].

Kannan, AM ;

Manthiram, A .

ELECTROCHEMICAL AND SOLID STATE LETTERS, 2002, 5 (07) :A167-A169

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