A Low-Cost, Self-Standing NiCo2O4@CNT/CNT Multilayer Electrode for Flexible Asymmetric Solid-State Supercapacitors

作者：Wu, Peng; Cheng, Shuang^*; Yao, Minghai; Yang, Lufeng; Zhu, Yuanyuan; Liu, Peipei; Xing, Ou; Zhou, Jun; Wang, Mengkun; Luo, Haowei; Liu, Meilin^*

来源：Advanced Functional Materials, 2017, 27(34): 1702160.

DOI：10.1002/adfm.201702160

• supercapacitors
• all-solid-state supercapacitors
• asymmetric supercapacitors
• flexible and self-standing films
• NiCo2O4@CNT composites

The demand for a new generation of flexible, portable, and high-capacity power sources increases rapidly with the development of advanced wearable electronic devices. Here we report a simple process for large-scale fabrication of self-standing composite film electrodes composed of NiCo2O4@carbon nanotube (CNT) for supercapacitors. Among all composite electrodes prepared, the one fired in air displays the best electrochemical behavior, achieving a specific capacitance of 1,590 F g(-1) at 0.5 A g(-1) while maintaining excellent stability. The NiCo2O4@CNT/CNT film electrodes are fabricated via stacking NiCo2O4@CNT and CNT alternately through vacuum filtration. Lightweight, flexible, and self-standing film electrodes (approximate to 24.3 mu m thick) exhibit high volumetric capacitance of 873 F cm(-3) (with an areal mass of 2.5 mg cm(-2)) at 0.5 A g(-1). An all-solid-state asymmetric supercapacitor consists of a composite film electrode and a treated carbon cloth electrode has not only high energy density (approximate to 27.6 Wh kg(-1)) at 0.55 kW kg(-1) (including the weight of the two electrodes) but also excellent cycling stability (retaining approximate to 95% of the initial capacitance after 5000 cycles), demonstrating the potential for practical application in wearable devices.

• 出版日期2017-9-13
• 单位华南理工大学