Phase Transformations in TiS2 during K Intercalation

被引：111

作者：

Tian, Bingbing ^{[1
,2
,3
]}

Tang, Wei ^{[4
]}

Leng, Kai ^{[2
,3
]}

Chen, Zhongxin ^{[2
,3
]}

Tan, Sherman Jun Rong ^{[2
,3
]}

Peng, Chengxin ^{[2
,3
]}

Ning, Guo-Hong ^{[2
,3
]}

Fu, Wei ^{[2
,3
]}

Su, Chenliang ^{[1
,2
,3
]}

Zheng, Guangyuan Wesley ^{[4
]}

Loh, Kian Ping ^{[1
,2
,3
]}

机构：

[1] Shenzhen Univ, Int Collaborat Lab Mat Optoelect Sci & Technol 2D, Coll Optoelect Engn, Key Lab Optoelect Devices & Syst,Minist Educ & Gu, Shenzhen 518060, Peoples R China

[2] Natl Univ Singapore, Dept Chem, CA2DM, 3 Sci Dr 3, Singapore 117543, Singapore

[3] Natl Univ Singapore, Graphene Res Ctr, 3 Sci Dr 3, Singapore 117543, Singapore

[4] ASTAR, Inst Mat Res & Engn, 2 Fusionopolis Way, Singapore 138634, Singapore

来源：

ACS ENERGY LETTERS | 2017年 / 2卷 / 08期

基金：

中国国家自然科学基金;

关键词：

POTASSIUM-ION BATTERIES; ELECTRODES; STORAGE; SODIUM; ANODES;

D O I：

10.1021/acsenergylett.7b00529

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 electrochemical performances of TiS2 in potassium ion batteries (KIBs) are poor due to the large size of K ions, which induces irreversible structural changes and poor kinetics. To obtain detailed insights into the kinetics of phase changes, we investigated the electrochemical properties, phase transformations, and stability of potassium-intercalated TiS2 (KxTiS2, 0 <= x <= 0.88). In situ XRD reveals staged transitions corresponding to distinct crystalline phases during K ion intercalation, which are distinct from those of Li and Na ions. Electrochemical (cyclic voltammetry and galvanostatic charge/discharge) studies show that the phase transitions among various intercalated stages slow down the kinetics of the discharge/charge in bulk TiS2 hosts. By chemically prepotassiating the bulk TiS2 (K0.25TiS2) to reduce the domain size of the crystal, these phase transitions are bypassed and more facile ion insertion kinetics can be obtained, which leads to improved Coulombic efficiency, rate capability, and cycling stability.

引用

页码：1835 / 1840

页数：6

共 30 条

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