title: Facile Preparation of Graphene/SnO₂ Xerogel Hybrids as the Anode Material in Li-Ion Batteries.
abstract: SnO2 has been considered as one of the most promising anode materials for Li-ion batteries due to its theoretical ability to store up to 8.4 Li(+). However, it suffers from poor rate performance and short cycle life due to the low intrinsic electrical conductivity and particle pulverization caused by the large volume change upon lithiation/delithiation. Here, we report a facile synthesis of graphene/SnO2 xerogel hybrids as anode materials using epoxide-initiated gelation method. The synthesized hybrid materials (19% graphene/SnO2 xerogel) exhibit excellent electrochemical performance: high specific capacity, stable cyclability, and good rate capability. Even cycled at a high current density of 1 A/g for 300 cycles, the hybrid electrode can still deliver a specific capacity of about 380 mAh/g, corresponding to more than 60% capacity retention. The incorporation of graphene sheets provides fast electron transfer between the interfaces of the graphene nanosheets and the SnO2 and a short lithium ion diffusion path. The porous structure of graphene/xerogel and the strong interaction between SnO2 and graphene can effectively accommodate the volume change and tightly confine the formed Li2O and Sn nanoparticles, thus preventing the irreversible capacity degradation.
authors.affiliation: Department of Mechanical Engineering, Indiana University-Purdue University Indianapolis , Indianapolis, Indiana 46202, United States.
authors.forename: Zhe-Fei
authors.initials: ZF
authors.lastname: Li
authors.affiliation: Department of Mechanical Engineering, Indiana University-Purdue University Indianapolis , Indianapolis, Indiana 46202, United States.
authors.forename: Qi
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Department of Mechanical Engineering, Indiana University-Purdue University Indianapolis , Indianapolis, Indiana 46202, United States.
authors.forename: Yadong
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Mechanical Engineering, Indiana University-Purdue University Indianapolis , Indianapolis, Indiana 46202, United States.
authors.forename: Fan
authors.initials: F
authors.lastname: Yang
authors.affiliation: Department of Mechanical Engineering, Indiana University-Purdue University Indianapolis , Indianapolis, Indiana 46202, United States.
authors.forename: Le
authors.initials: L
authors.lastname: Xin
authors.affiliation: Department of Mechanical Engineering, Indiana University-Purdue University Indianapolis , Indianapolis, Indiana 46202, United States.
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhou
authors.forename: Hangyu
authors.initials: H
authors.lastname: Zhang
authors.forename: Lia
authors.initials: L
authors.lastname: Stanciu
authors.affiliation: Department of Mechanical Engineering, Indiana University-Purdue University Indianapolis , Indianapolis, Indiana 46202, United States.
authors.forename: Jian
authors.initials: J
authors.lastname: Xie
keywords: Li-ion battery; SnO2; anode; graphene; hybrids; xerogel