title: Graphene quantum dots coated VO2 arrays for highly durable electrodes for Li and Na ion batteries.
abstract: Nanoscale surface engineering is playing important role in enhancing the performance of battery electrode. VO2 is one of high-capacity but less-stable materials and has been used mostly in the form of powders for Li-ion battery cathode with mediocre performance. In this work, we design a new type of binder-free cathode by bottom-up growth of biface VO2 arrays directly on a graphene network for both high-performance Li-ion and Na-ion battery cathodes. More importantly, graphene quantum dots (GQDs) are coated onto the VO2 surfaces as a highly efficient surface "sensitizer" and protection to further boost the electrochemical properties. The integrated electrodes deliver a Na storage capacity of 306 mAh/g at 100 mA/g, and a capacity of more than 110 mAh/g after 1500 cycles at 18 A/g. Our result on Na-ion battery may pave the way to next generation postlithium batteries.
authors.affiliation: School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.
authors.forename: Dongliang
authors.initials: D
authors.lastname: Chao
authors.forename: Changrong
authors.initials: C
authors.lastname: Zhu
authors.forename: Xinhui
authors.initials: X
authors.lastname: Xia
authors.forename: Jilei
authors.initials: J
authors.lastname: Liu
authors.forename: Xiao
authors.initials: X
authors.lastname: Zhang
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
authors.forename: Pei
authors.initials: P
authors.lastname: Liang
authors.forename: Jianyi
authors.initials: J
authors.lastname: Lin
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.forename: Ze Xiang
authors.initials: ZX
authors.lastname: Shen
authors.forename: Hong Jin
authors.initials: HJ
authors.lastname: Fan
keywords: Vanadium oxides; graphene quantum dots; lithium ion battery; nanoarray electrodes; sodium ion battery