Flexible and high energy density asymmetrical supercapacitors based on core/shell conducting polymer nanowires/manganese dioxide nanoflakes
Flexible and high energy density asymmetrical supercapacitors based on core/shell conducting polymer nanowires/manganese dioxide nanoflakes
复制标题
基于核/壳导电聚合物纳米线/二氧化锰纳米片的柔性高能量密度不对称超级电容器
DOI：
10.1016/j.nanoen.2017.03.045
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发表时间：
2017-05-01
期刊：
影响因子：
17.6
通讯作者：
Zhai, Tianyou
中科院分区：
文献类型：
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作者：
He, Weidong;Wang, Chenggang;Zhai, Tianyou
以聚吡咯（PPy）纳米线为核缓冲层，K-Birnessite型二氧化锰（MnO 2）为壳层，通过一种简单、方便、环境友好的方法成功构建了多级多孔聚吡咯纳米线/氧化锰纳米片（MnO 2 NFs@PPy NWs）核/壳纳米结构。核/壳纳米结构有效地增加了活性表面积，减小了离子传输距离，有利于离子的高效传输。MnO 2 NFs@PPy纳米线核/壳结构不仅表现出高的比电容（2A g（-1）时为276 F g（-1）），而且由于结合了MnO 2和PPy的优点而产生的协同效应，在极端充放电条件下的电容保持率（20 A g（-1）时为200 F g（-1））为72.5%。使用这种分级纳米结构作为正极，我们进一步证明了超柔性非对称超级电容器（AFSC）（MnO2@PPy//AC）具有优异的循环稳定性（在3 A g（-1）下6000次循环后90.3%），机械柔韧性，大电压操作窗口（1.8-2.0 V vs. SCE）和所有充电/放电条件下的高能量密度（功率密度为901.7 W kg（-1）时为25.8 W h kg（-1），功率密度为9000 W kg（-1）时为17.1 W h kg（-1））。
Hierarchically porous polypyrrole nanowires/manganese oxides nanoflakes (MnO2 NFs@PPy NWs) core/shell nanostructures were successfully constructed through a simple, convenient and environmentally friendly method by using PPy nanowires as the core buffer and K-Birnessite type MnO2 as the shell. The core/shell nanostructures effectively increase active surface areas and decrease the ion transmission distance, which is conducive to the efficient transfer of ions. The MnO2 NFs@PPy NWs core/shell nanostructures exhibited not only high specific capacitance (276 F g(-1) at 2 A g(-1)) but also excellent capacitance retained ratio of 72.5% under extreme charge/discharge conditions (200 F g(-1) at 20 A g(-1)) due to the synergistic effect by combining the merits of MnO2 and PPy. Using such hierarchical nanostructure as the positive electrode, we further demonstrate that ultra-flexible asymmetrical supercapacitors (AFSCs) (MnO2@PPy//AC) possess excellent cycling stability (90.3% after 6000 cycles at 3 A g (-1)), mechanical flexibility, large voltage operation window (1.8-2.0 V vs. SCE) and high energy densities at all charge/discharge conditions (25.8 W h kg(-1) at the power density of 901.7 W kg(-1), and 17.1 W h kg(-1) at the power density of 9000 W kg(-1), respectively).