CoNi2S4 Nanoparticle/Carbon Nanotube Sponge Cathode with Ultrahigh Capacitance for Highly Compressible Asymmetric Supercapacitor. Issue 27 (30th May 2018)

• Record Type: Journal Article
• Authors: Cao, Xin; He, Jin; Li, Huan; Kang, Liping; He, Xuexia; Sun, Jie; Jiang, Ruibing; Xu, Hua; Lei, Zhibin; Liu, Zong‐Huai
• Is Part Of: Small. Volume 14:Issue 27(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-05-30
• Subjects: asymmetric supercapacitors -- CNT sponges -- compressible -- CoNi2S4 -- electrodepositing; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.201800998
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: Compared with other flexible energy‐storage devices, the design and construction of the compressible energy‐storage devices face more difficulty because they must accommodate large strain and shape deformations. In the present work, CoNi2 S4 nanoparticles/3D porous carbon nanotube (CNT) sponge cathode with highly compressible property and excellent capacitance is prepared by electrodepositing CoNi2 S4 on CNT sponge, in which CoNi2 S4 nanoparticles with size among 10–15 nm are uniformly anchored on CNT, causing the cathode to show a high compression property and gives high specific capacitance of 1530 F g −1 . Meanwhile, Fe2 O3 /CNT sponge anode with specific capacitance of 460 F g −1 in a prolonged voltage window is also prepared by electrodepositing Fe2 O3 nanosheets on CNT sponge. An asymmetric supercapacitor (CoNi2 S4 /CNT//Fe2 O3 /CNT) is assembled by using CoNi2 S4 /CNT sponge as positive electrode and Fe2 O3 /CNT sponge as negative electrode in 2m KOH solution. It exhibits excellent energy density of up to 50 Wh kg −1 at a power density of 847 W kg −1 and excellent cycling stability at high compression. Even at a strain of 85%, about 75% of the initial capacitance is retained after 10 000 consecutive cycles. The CoNi2 S4 /CNT//Fe2 O3 /CNT device is a promising candidate for flexible energy devices due to its excellent compressibility and high energy density. Abstract : The asymmetric supercapacitor (CoNi2 S4 /carbon nanotube (CNT)//Fe2 O3 /CNT) is assembled by using CoNi2 S4 /CNT sponge as positive electrode and Fe2 O3 /CNT sponge as negative electrode in 2m KOH solution. The assembled device exhibits not only excellent energy density of up to 50 Wh kg −1 at a power density of 847 W kg −1, but also shows the structural stability with nearly full recovery from 80% strain.