Ultrathin Metal-Organic Framework Nanosheet-Derived Ultrathin Co3O4 Nanomeshes with Robust Oxygen-Evolving Performance and Asymmetric Supercapacitors
Ultrathin Metal-Organic Framework Nanosheet-Derived Ultrathin Co3O4 Nanomeshes with Robust Oxygen-Evolving Performance and Asymmetric Supercapacitors
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超薄金属有机框架纳米片衍生的超薄 Co3O4 纳米网，具有强大的析氧性能和不对称超级电容器
DOI：
10.1021/acsami.8b04026
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发表时间：
2018
影响因子：
9.5
通讯作者：
An Changhua
中科院分区：
文献类型：
--
作者：
Wei Guijuan;Zhou Zhen;Zhao Xixia;Zhang Weiqing;An Changhua
超薄金属有机骨架（MOF）纳米片具有二维（2D）特征和MOF的固有优势，吸引了广泛的研究兴趣。直接制备MOF纳米片至今仍是一个挑战。在这里，我们已经开发了一种新的自下而上的方法来合成沸石咪唑骨架-67（ZIF-67）纳米片，它可以在热处理后原位转化为Co 3 O 4纳米网。有趣的是，所获得的Co 3 O 4纳米网富含氧缺陷，为法拉第反应提供了丰富的活性位点。该修饰电极具有较大的比电容（1216.4F g-1at 1A g-1）和较高的倍率性能（925.5F g-1at 20 A g-1）。此外，由Co 3 O 4//活性炭制成的非对称超级电容器在790.7 W kg-1下显示出46.5 Wh kg-1的能量密度。此外，2D Co 3 O 4纳米网显示出优异的析氧反应性能，在起始电位处具有230 mV的过电位和74.0 mV dec-1的小Tafel斜率。本发明的方法为制备在能量催化和转换中具有各种应用的其他2D纳米金属氧化物纳米结构提供了一种简便的途径。
Ultrathin metal–organic framework (MOF) nanosheets possessing inherent advantages of both two-dimensional (2D) features and MOFs are attracting intensive research interest. The direct manufacture of MOF nanosheets is still a challenge up to now. Here, we have developed a novel bottom-up approach to synthesize zeolitic imidazolate framework-67 (ZIF-67) nanosheets, which can be in situ converted into Co3O4ultrathin nanomeshes after thermal treatment. Interestingly, the obtained Co3O4nanomeshes are rich in oxygen defects, providing fruitful active sites for the faradaic reaction. The modified electrode exhibits a large specific capacitance (1216.4 F g–1at 1 A g–1), as well as a high rate capability (925.5 F g–1at 20 A g–1). Moreover, an asymmetric supercapacitor made of Co3O4//activated carbon shows an energy density of 46.5 Wh kg–1at 790.7 W kg–1. Furthermore, the 2D Co3O4ultrathin nanomeshes show an outstanding performance for the oxygen evolution reaction with an overpotential of 230 mV at the onset potential and a small Tafel slope of 74.0 mV dec–1. The present method presents a facile avenue to the preparation of other 2D ultrathin metal oxide nanostructures with various applications in energy catalysis and conversion.