Three-Dimensional Rebar Graphene
Three-Dimensional Rebar Graphene
复制标题
三维钢筋石墨烯。
DOI：
10.1021/acsami.6b12503
复制
发表时间：
2017-03-01
影响因子：
9.5
通讯作者：
Tour, James M.
中科院分区：
文献类型：
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作者：
Sha, Junwei;Salvatierra, Rodrigo V.;Tour, James M.
以多壁碳纳米管（MWCNTs）为增强材料，烧结镍骨架为模板和催化剂，蔗糖为固体碳源，采用粉末冶金模板法制备了自支撑的坚固的三维（3D）钢筋型石墨烯泡沫（GF）.作为不同石墨烯片和碳壳之间的增强和桥梁，MWCNT改善了3D GF的热稳定性、储能模量（290.1 kPa）和电导率（21.82 S cm（-1）），从而产生高孔隙率和结构稳定的3D钢筋GF。3D钢筋GF可以支撑> 3150倍的泡沫重量而没有不可逆的高度变化，并且在加载> 8500倍的泡沫重量后仅显示出类似于25%的不可逆高度变化。3D钢筋GF还显示出作为锂离子电容器（LIC）中的高度多孔电极的稳定性能，其能量密度为32 Wh kg（-1）。在6.50 mA cm（-2）的高电流密度下进行500次循环测试后，LIC显示出78%的能量密度保持率。这些特性表明3D钢筋GF在需要稳定的机械和电化学特性的设备中具有很好的应用前景。
Free-standing robust three-dimensional (3D) rebar graphene foams (GFs) were developed by a powder metallurgy template method with multiwalled carbon nanotubes (MWCNTs) as a reinforcing bar, sintered Ni skeletons as a template and catalyst, and sucrose as a solid carbon source. As a reinforcement and bridge between different graphene sheets and carbon shells, MWCNTs improved the thermostability, storage modulus (290.1 kPa) and conductivity (21.82 S cm (-1)) of 3D GF resulting in a high porosity and structurally stable 3D rebar GF. The 3D rebar GF can support >3150x the foam's weight with no irreversible height change, and shows only a similar to 25% irreversible height change after loading >8500X the foam's weight. The 3D rebar GF also shows stable performance as a highly porous electrode in lithium ion capacitors (LICs) with an energy density of 32 Wh kg (-1). After 500 cycles of testing at a high current density of 6.50 mA cm (-2), the LIC shows 78% energy density retention. These properties indicate promising applications with 3D rebar GFs in devices requiring stable mechanical and electrochemical properties.