期刊
ADVANCED MATERIALS
卷 30, 期 27, 页码 -出版社
WILEY-V C H VERLAG GMBH
DOI: 10.1002/adma.201800036
关键词
anode materials; electrochemical property; high capacity; potassium-ion battery; VSe2 ultrathin nanosheet
类别
资金
- National Natural Science Foundation of China [51671003]
- National Key Research and Development Program of China [2016YFB0100201]
- Open Project Foundation of State Key Laboratory of Chemical Resource Engineering
- Young Thousand Talents Program
- Peking University
Potassium-ion batteries (KIBs) are receiving increasing interest in grid-scale energy storage owing to the earth abundant and low cost of potassium resources. However, their development still stays at the infancy stage due to the lack of suitable electrode materials with reversible depotassiation/potassiation behavior, resulting in poor rate performance, low capacity, and cycling stability. Herein, the first example of synthesizing single-crystalline metallic graphene-like VSe2 nanosheets for greatly boosting the performance of KIBs in term of capacity, rate capability, and cycling stability is reported. Benefiting from the unique 2D nanostructure, high electron/K+-ion conductivity, and outstanding pseudocapacitance effects, ultrathin VSe2 nanosheets show a very high reversible capacity of 366 mAh g(-1) at 100 mA g(-1), a high rate capability of 169 mAh g(-1) at 2000 mA g(-1), and a very low decay of 0.025% per cycle over 500 cycles, which are the best in all the reported anode materials in KIBs. The first-principles calculations reveal that VSe2 nanosheets have large adsorption energy and low diffusion barriers for the intercalation of K+-ion. Ex situ X-ray diffraction analysis indicates that VSe2 nanosheets undertake a reversible phase evolution by initially proceeding with the K+-ion insertion within VSe2 layers, followed by the conversion reaction mechanism.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据