Flexible, sandwich-like CNTs/NiCo 2 O 4 hybrid paper electrodes for all-solid state supercapacitors

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2017, Vol.5 (12), p.5886-5894
• Main Authors: Zheng, Yongjia, Lin, Zhiqiang, Chen, Wenjun, Liang, Binghao, Du, Huiwei, Yang, Rongliang, He, Xianfeng, Tang, Zikang, Gui, Xuchun
• Format: Article
• Language: English
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/C7TA00491E

With the increasing demand for compact storage systems for portable and wearable electronic devices, flexible supercapacitors with high volumetric performance have attracted considerable attention. Here, we report a simple method to fabricate a sandwich-like carbon nanotubes (CNTs)/NiCo 2 O 4 hybrid paper electrode, consisting of a layer of conductive CNT buckypaper coated with honeycomb-like NiCo 2 O 4 nanosheets at both sides. Owing to the high conductivity of the CNT skeleton and vertically aligned structure of NiCo 2 O 4 nanosheets, the free-standing hybrid paper possesses an ultra-high specific capacitance of 1752.3 F g −1 and excellent cycling performance. A flexible all-solid-state symmetrical supercapacitor has been further assembled based on the hybrid paper. The device exhibits excellent volumetric energy and power densities (1.17 mW h cm −3 and 2430 mW cm −3 ) and deformability, even under bending at an angle of 180°. The hybrid paper can serve as a freestanding and flexible electrode for various energy devices.