Li Intercalation into Graphite: Direct Optical Imaging and Cahn-Hilliard Reaction Dynamics

被引：98

作者：

Guo, Yinsheng ^{[1
]}

Smith, Raymond B. ^{[3
]}

Yu, Zhonghua ^{[1
]}

Efetov, Dmitri K. ^{[2
]}

Wang, Junpu ^{[2
]}

Kim, Philip ^{[2
]}

Bazant, Martin Z. ^{[3
,4
]}

Brus, Louis E. ^{[1
]}

机构：

[1] Columbia Univ, Dept Chem, New York, NY 10027 USA

[2] Columbia Univ, Dept Phys, New York, NY 10027 USA

[3] MIT, Dept Chem Engn, Cambridge, MA 02139 USA

[4] MIT, Dept Math, Cambridge, MA 02139 USA

来源：

JOURNAL OF PHYSICAL CHEMISTRY LETTERS | 2016年 / 7卷 / 11期

基金：

美国国家科学基金会;

关键词：

LITHIUM-ION; NONEQUILIBRIUM THERMODYNAMICS; STAGE TRANSFORMATION; DIELECTRIC FUNCTION; BATTERY ELECTRODES; PHASE; DIFFUSION; KINETICS; TRANSITIONS; MICROSCOPY;

D O I：

10.1021/acs.jpclett.6b00625

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：

Lithium intercalation into graphite is a critical process in energy storage technology. Studies of Li intercalation kinetics have proved challenging due to structural and phase complexity, and sample heterogeneity. Here we report direct time- and space-resolved, all-optical measurement of Li intercalation. We use a single crystal graphite electrode with lithographically defined disc geometry. All-optical, Raman and reflectance measurements distinguish the intrinsic intercalation process from side reactions, and provide new insight into the microscopic intercalation process. The recently proposed Cahn-Hilliard reaction (CHR) theory quantitatively captures the observed phase front spatial patterns and dynamics, using a two-layer free-energy model with novel, generalized Butler-Volmer kinetics. This approach unites Cahn-Hilliard and electrochemical kinetics, using a thermodynamically consistent description of the Li injection reaction at the crystal edge that involves a cooperative opening of graphene planes. The excellent agreement between experiment and theory presented here, with single-crystal resolution, provides strong support for the CHR theory of solid-state reactions.

引用

页码：2151 / 2156

页数：6