Building layered NixCo2x(OH)(6x) nanosheets decorated three-dimensional Ni frameworks for electrochemical applications
Building layered NixCo2x(OH)(6x) nanosheets decorated three-dimensional Ni frameworks for electrochemical applications
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构建层状 NixCo2x(OH)(6x) 纳米片装饰的三维 Ni 框架用于电化学应用
DOI：
10.1016/j.jpowsour.2016.03.085
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发表时间：
2016
影响因子：
9.2
通讯作者：
Su Yu-Zhi
中科院分区：
文献类型：
--
作者：
Liu Zhao-Qing;Chen Gao-Feng;Zhou Pei-Lin;Li Nan;Su Yu-Zhi
为了在能量存储和转换装置中实现高电化学性能，过渡金属氢氧化物电极材料需要增强其固有的差电导率并充分利用其未开发的活性位点。因此，开发了一种简单有效的策略，使用双三维 Ni 作为结构和导电支撑系统来合成层状 NixCo2x(OH)6x 纳米片。由于高导电性、丰富的互连离子/电子传输路径和强大的结构稳定性，NixCo2x(OH)6x@Ni电极表现出极高的比电容、优异的倍率性能和优异的循环稳定性。此外，由NixCo2x(OH)6x@Ni和活性炭/碳纳米管组装的非对称超级电容器实现了1.5 V的大工作电压窗口、高能量密度（约44.2 Wh kg−1，功率密度为750 W kg−1）和出色的长期循环能力（5000次循环后仍保持100%的初始Csp）。此外，NixCo2x(OH)6x@Ni 作为析氧反应电催化剂，具有较小的起始过电势 (263 mV)、较低的塔菲尔斜率 (78 mV dec−1)、在 336 mV 的低过电势下具有 30 mA cm−2 的大阳极电流密度和突出的电化学耐久性。
To achieve high electrochemical performance in energy storage and conversion devices, transition metal hydroxides electrode materials need enhancing their intrinsic poor conductivity and fully utilizing their unexploited active sites. Accordingly, a simple and effective strategy is developed to synthesize layered NixCo2x(OH)6xnanosheets using dual three-dimensional Ni as structural and conductive support system. Owing to highly electrical conductivity, rich of interconnected ion/electron transport pathways, and robust structure stability, NixCo2x(OH)6x@Ni electrode exhibits remarkably high specific capacitance, excellent rate capability, and superior cycle stability. Moreover, the asymmetric supercapacitor assembled by NixCo2x(OH)6x@Ni and activated carbon/carbon nanotube achieves a large working voltage window of 1.5 V, a high energy density (≈44.2 Wh kg−1at a power density of 750 W kg−1) and outstanding long-term cycle ability (remaining 100% of the initialCspafter 5000 cycles). Furthermore, the NixCo2x(OH)6x@Ni as an oxygen evolution reaction electrocatalyst shows small onset overpotential (263 mV), low Tafel slope (78 mV dec−1), large anodic current density of 30 mA cm−2at a low overpotential of 336 mV and prominent electrochemical durability.