Oxygen Bridges between NiO Nanosheets and Graphene for Improvement of Lithium Storage

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	Oxygen Bridges between NiO Nanosheets and Graphene for Improvement of Lithium Storage
	G. M. Zhou; D. W. Wang; L. C. Yin; N. Li; F. Li; H. M. Cheng
	2012
发表期刊	Acs Nano
ISSN	1936-0851
卷号	6 期号:4 页码:3214-3223
摘要	Graphene has been widely used to dramatically improve the capacity, rate capability, and cycling performance of nearly any electrode material for batteries. However, the binding between graphene and these electrode materials has not been dearly elucidated. Here we report oxygen bridges between graphene with oxygen functional groups and NiO from analysis by X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy and confirm the conformation of oxygen bridges by the first-principles calculations. We found that NiO nanosheets (NiO NSs) are bonded strongly to graphene through oxygen bridges. The oxygen bridges mainly originate from the pinning of hydroxyl/epoxy groups from graphene on the Ni atoms of NiO NSs. The calculated adsorption energies (137 and 1.84 eV for graphene with hydroxyl and epoxy) of a Ni adatom on oxygenated graphene by binding with oxygen are comparable with that on graphene (126 eV). However, the calculated diffusion barriers of the Ni adatom on the oxygenated graphene surface (223 and 1.69 eV for graphene with hydroxyl and epoxy) are much larger than that on the graphene (0.19 eV). Therefore, the NiO NS is anchored strongly on the graphene through a C-O-Ni bridge, which allows a high reversible capacity and excellent rate performance. The easy binding/difficult dissociating characteristic of Ni adatoms on the oxygenated graphene facilitates fast electron hopping from graphene to NiO and thus the reversible lithiation and delithiation of NiO. We believe that the understanding of this oxygen bridge between graphene and NiO will lead to the development of other high-performance electrode materials.
部门归属	[zhou, guangmin; yin, li-chang; li, na; li, feng; cheng, hui-ming] chinese acad sci, inst met res, shenyang natl lab mat sci, shenyang 110016, peoples r china. [wang, da-wei] univ queensland, australian inst bioengn & nanotethnol, arc ctr excellence funct nanomat, brisbane, qld 4072, australia.;li, f (reprint author), chinese acad sci, inst met res, shenyang natl lab mat sci, 72 wenhua rd, shenyang 110016, peoples r china.;fli@imr.ac.cn
关键词	Graphene Nio Nanosheets Oxygen Bridge Oxygen Functional Groups Density Functional Theory Lithium Ion Batteries Li-ion Batteries Negative-electrode Materials Augmented-wave Method Minimum Energy Paths Elastic Band Method Anode Material Nanostructured Materials Reversible Capacity Cyclic Performance Saddle-points
URL	查看原文
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/60524
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	G. M. Zhou,D. W. Wang,L. C. Yin,et al. Oxygen Bridges between NiO Nanosheets and Graphene for Improvement of Lithium Storage[J]. Acs Nano,2012,6(4):3214-3223.
APA	G. M. Zhou,D. W. Wang,L. C. Yin,N. Li,F. Li,&H. M. Cheng.(2012).Oxygen Bridges between NiO Nanosheets and Graphene for Improvement of Lithium Storage.Acs Nano,6(4),3214-3223.
MLA	G. M. Zhou,et al."Oxygen Bridges between NiO Nanosheets and Graphene for Improvement of Lithium Storage".Acs Nano 6.4(2012):3214-3223.