Oxygen vacancy-rich mesoporous W18O49 nanobelts with ultrahigh initial Coulombic efficiency toward high-performance lithium storage. (1st January 2016)

• Record Type: Journal Article
• Authors: Sun, Ying; Wang, Wei; Qin, Jinwen; Zhao, Di; Mao, Baoguang; Xiao, Ying; Cao, Minhua
• Is Part Of: Electrochimica acta. Volume 187(2016)
• Page Start: 329
• Page End: 339
• Publication Date: 2016-01-01
• Subjects: W18O49 -- Mesoporous -- Oxygen Vacancies -- Anode Materials -- Lithium-ion batteries; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2015.11.064
• Languages: English
• ISSNs: 0013-4686

Abstract

ABSTRACT: Developing new anode materials with high initial Coulombic efficiency, specific capacity, and rate performance is still a great challenge for the next generation of rechargeable lithium-ion batteries (LIBs). Herein, we demonstrated the synthesis of mesoporous W18 O49 nanobelts (m-W18 O49 NBs) with rich oxygen vacancies (O-vacancies) by a simple solvothermal method followed by a calcination treatment without any templates and catalysts. When used as an anode material in LIBs, m-W18 O49 NBs electrode exhibits an ultrahigh initial Coulombic efficiency of 96.3% and at the same time it also displays higher specific capacity, better cycling stability and excellent rate capability compared with bulk W18 O49 (b-W18 O49 ) and mesoporous WO3 nanobelts (m-WO3 NBs) electrodes. The excellent lithium storage performance of the m-W18 O49 NBs can be ascribed to three factors: (I) abundant O-vacancies increased electronic conductivity and offered sufficient active sites for conversion reactions; (II) mesoporous structure allowed for easy diffusion of the electrolyte and at the same time it can enhance the m-W18 O49 NBs/electrolyte contact area, shorten the Li + diffusion length, and accommodated the strain induced by the volume change during the electrochemical reaction; (III) one dimensional (1D) nanobelts were more beneficial for electron transport.