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	石墨烯包裹Cu_(2+1)O/Cu复合材料的制备及其储锂性能; Fabrication and Lithium-Storage Performances of Graphene-Wrapped Cu_(2+1)O/Cu Composites
	田雷雷 ; 魏贤勇 ; 庄全超 ; 宗志敏 ; 孙世刚
	2013-09-15
关键词	石墨烯 氧化亚铜 半导体 异质结 锂离子电池 电子输运 graphene cuprous oxide semiconductor heterojunction lithium ion batteries electron transport
英文摘要	半导体的能级结构和金属-半导体异质结的结构及性质对金属-半导体复合材料的导电性能具有重要影响.优化半导体相的能级结构和金属-半导体接触界面的势垒是增强金属-半导体型复合电极材料导电能力,提高复合电极材料储锂性能的重要途径.采用水热反应-原位热还原法制备石墨烯包覆Cu2+1O/Cu复合材料.根据SEM和Xrd研究结果,Cu2+1O(金属过剩型Cu2O)和Cu复合体被均匀包裹在柔性石墨烯层中.充放电结果表明,石墨烯包裹Cu2+1O/Cu复合材料电极具有较高的充放电容量和优异的循环性能,50 MA g-1充放电的首周充电和放电比容量分别为773和438 MA H g-1,60周的容量保持率为84%;同时也具有很好的倍率性能,表明石墨烯包裹Cu2+1O/Cu复合材料具有良好的金属-半导体异质结界面的结构和优异的导电性能.; Materials with hybrid metal-semiconductor nanostructures,such as graphene-metal oxides and carbon nanotube-metal oxides,have been intensively exploited as electrode material for lithium ion batteries in recent years.It was found that the structures and properties of the metal-semiconductor herterojunction and the energy level structures of the semiconductor are essential for the conductance of the metal-semiconductor composite.It is thence believed that the conductance,and thus the lithium-storage performance,of the metal-semiconductor composite can be improved by tuning the structures of the metal-semiconductor herterojunction and the energy level structures of the semiconductor.Metal excess defects can occured in metal oxide crystals due to the anions are absent from their lattice sites or the presence of extra cations at interstitial sites.In the metal excess type metal oxide,the electric transport is mainly by "excess" electrons which are present for maintaining the electrical neutrality,and thus possesses a higher conductance.In this work,graphene-wrapped Cu2+1O/Cu composites were successfully fabricated by using a hydrothermal reaction followed by an in situ thermal reduction.The structures,surface morphologies and the lithium-storage performances of the obtained materials were characterized and investigated by scanning electron microscopy,X-ray diffraction and galvanostatic discharge-charge techniques.In the obtained hybrid material,highly-crystallized Cu2+1O(Cu2O with metal excess defects) successfully formed during the heat treatment processes,Cu2+1O and Cu particles were homogeneously wrapped by flexible graphene sheets with a well defined core-shell structure.Constant current charge-discharge results showed that graphene-wrapped Cu2+1O/Cu composite had a higher reversible capacity and excellent cycling stability,delivered a higher initial charge-discharge capacity of 773 and 438 mA h g-1at 50 mA g-1and superb cycling performance of 368 mA h g-1after 60 cycles,as well as a favorable rate capabilities and high rate cycling performances,indicating the high conductance and the optimized herterojunctions were achieved by the simultaneously introduction of metal excess defects,metallic copper and graphene in graphene-wrapped Cu2+1 O/Cu composites.; 国家自然科学基金创新研究群体科学基金(No.51221462); 江苏省研究生培养创新工程(No.CXZZ12_0943); 江苏高校优势学科建设工程资助~~
语种	zh_CN
内容类型	期刊论文
源URL	[http://dspace.xmu.edu.cn/handle/2288/98430]
专题	材料学院－已发表论文
推荐引用方式 GB/T 7714	田雷雷,魏贤勇,庄全超,等. 石墨烯包裹Cu_(2+1)O/Cu复合材料的制备及其储锂性能, Fabrication and Lithium-Storage Performances of Graphene-Wrapped Cu_(2+1)O/Cu Composites[J],2013.
APA	田雷雷,魏贤勇,庄全超,宗志敏,&孙世刚.(2013).石墨烯包裹Cu_(2+1)O/Cu复合材料的制备及其储锂性能..
MLA	田雷雷,et al."石墨烯包裹Cu_(2+1)O/Cu复合材料的制备及其储锂性能".(2013).

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