title: Freestanding MoO2/Mo2C imbedded carbon fibers for Li-ion batteries.
abstract: Flexible and freestanding MoO2/Mo2C imbedded carbon fibers (MoO2/Mo2C ICFs) have been successfully synthesized via an integrated procedure including electrospinning, thermo-plastication in air and reduction/carbonization at high temperature. A series of techniques such as SEM, TEM, N2adsorption-desorption analysis, XRD, TGA, IR and XPS have been employed to systemically characterize the MoO2/Mo2C ICFs. In particular, it is observed that the MoO2/Mo2C ICFs derived from phosphomolybdic acid have more highly porous structures than those derived from molybdic acid. Most impressively, the obtained MoO2/Mo2C ICFs are directly used as binder- and current collector-free anode materials for LIBs, which exhibit desirable rate capability and satisfactory cycling performance. The electrochemical investigations illustrated that the MoO2/Mo2C ICFs could deliver an initial discharging capacity of 1422.0 mA h g-1with an original coulombic efficiency of 63.3%, and the subsequent reversible capacity could reach as high as 1103.6 mA h g-1even after 70 cycles at a current density of 0.1 A g-1. Such a capacity is larger than the theoretical capacity of MoO2(838 mA h g-1) and pure carbon fibers (460.5 mA h g-1). More importantly, the MoO2/Mo2C ICFs exhibited an excellent rate performance with a capacity of 445.4 mA h g-1even at a charging current density of 1.6 A g-1. The remarkable enhancement in rate capability and long cycling performance resulted from a synergistic effect between the MoO2nanoparticles and porous carbon fiber matrix. This methodology can be widely extended to fabricate other metal oxide/carbon composites for significant energy storage and conversion applications.
authors.affiliation: College of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang 330031, China. huizhu@ncu.edu.cn.
authors.forename: Hongqin
authors.initials: H
authors.lastname: Li
authors.affiliation: College of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang 330031, China. huizhu@ncu.edu.cn.
authors.forename: Haijun
authors.initials: H
authors.lastname: Ye
authors.affiliation: College of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang 330031, China. huizhu@ncu.edu.cn.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Key Laboratory of Functional Materials and Devices for Special Environments, Xinjiang Technical Institute of Physics & Chemistry, Chinese Academy of Sciences, 40-1 South Beijing Road, Urumqi, Xinjiang 830011, China. yinjiao@ms.xjb.ac.cn.
authors.forename: Chuanyi
authors.identifier: http://orcid.org/0000-0002-7146-115X
authors.initials: C
authors.lastname: Wang
authors.affiliation: Key Laboratory of Functional Materials and Devices for Special Environments, Xinjiang Technical Institute of Physics & Chemistry, Chinese Academy of Sciences, 40-1 South Beijing Road, Urumqi, Xinjiang 830011, China. yinjiao@ms.xjb.ac.cn.
authors.forename: Jiao
authors.initials: J
authors.lastname: Yin
authors.affiliation: College of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang 330031, China. huizhu@ncu.edu.cn and State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, P. R. China.
authors.forename: Hui
authors.identifier: http://orcid.org/0000-0002-3921-9486
authors.initials: H
authors.lastname: Zhu