Amorphous Vanadium Oxide Matrixes Supporting Hierarchical Porous Fe3O4/Graphene Nanowires as a High-Rate Lithium Storage Anode
Amorphous Vanadium Oxide Matrixes Supporting Hierarchical Porous Fe3O4/Graphene Nanowires as a High-Rate Lithium Storage Anode
复制标题
支持分级多孔 Fe3O4/石墨烯纳米线作为高倍率锂存储阳极的非晶氧化钒基体
DOI：
10.1021/nl5025694
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发表时间：
2014-11-01
期刊：
影响因子：
10.8
通讯作者：
Mai, Liqiang
中科院分区：
文献类型：
--
作者：
An, Qinyou;Lv, Fan;Mai, Liqiang
开发具有高能量密度和高功率密度的电极材料是满足世界范围内能源存储迫切需求的关键。为了实现充放电过程中离子/电子的快速高效传输和结构稳定，采用相分离法制备了以非晶氧化钒为载体的分级多孔Fe 3 O 4/石墨烯纳米线。在不使用任何硬模板的情况下，由FeVO 4中心点1.1H（2）O@石墨烯纳米线沿着Fe 3 O 4的晶化和钒氧化物的非晶化直接原位构建多孔结构。分级多孔Fe 3 O 4/VOx/石墨烯纳米线表现出高的库仑效率和出色的可逆比容量（1146 mAh g（-1））。即使在5 A g（-1）的高电流密度下，多孔纳米线也保持类似于500 mAh g（-1）的可逆容量。此外，通过原位X射线衍射和X射线光电子能谱研究了分级多孔Fe 3 O 4/VOx/石墨烯纳米线的非晶化和Fe与Fe 3 O 4之间的转化反应.我们的工作表明，无定形钒氧化物基体支持分级多孔Fe 3 O 4/石墨烯纳米线是在储能应用中最有吸引力的阳极之一。
Developing electrode materials with both high energy and power densities holds the key for satisfying the urgent demand of energy storage worldwide. In order to realize the fast and efficient transport of ions/electrons and the stable structure during the charge/discharge process, hierarchical porous Fe3O4/graphene nanowires supported by amorphous vanadium oxide matrixes have been rationally synthesized through a facile phase separation process. The porous structure is directly in situ constructed from the FeVO4 center dot 1.1H(2)O@graphene nanowires along with the crystallization of Fe3O4 and the amorphization of vanadium oxide without using any hard templates. The hierarchical porous Fe3O4/VOx/graphene nanowires exhibit a high Coulombic efficiency and outstanding reversible specific capacity (1146 mAh g(-1)). Even at the high current density of 5 A g(-1), the porous nanowires maintain a reversible capacity of similar to 500 mAh g(-1). Moreover, the amorphization and conversion reactions between Fe and Fe3O4 of the hierarchical porous Fe3O4/VOx/graphene nanowires were also investigated by in situ X-ray diffraction and X-ray photoelectron spectroscopy. Our work demonstrates that the amorphous vanadium oxides matrixes supporting hierarchical porous Fe3O4/graphene nanowires are one of the most attractive anodes in energy storage applications.