Agglomerated nickel–cobalt layered double hydroxide nanosheets on reduced graphene oxide clusters as efficient asymmetric supercapacitor electrodes. Issue 9 (14th May 2020)

• Record Type: Journal Article
• Authors: Liu, Lu; Liu, Anru; Xu, Yuhan; Yu, Haoming; Yang, Fangqi; Wang, Jun; Zeng, Zheling; Deng, Shuguang
• Is Part Of: Journal of materials research. Volume 35:Issue 9(2020)
• Page Start: 1205
• Page End: 1213
• Publication Date: 2020-05-14
• Subjects: energy storage, -- microstructure, -- 2D materials, -- cluster assembly; Materials -- Research -- Periodicals; 620.1105
• DOI: 10.1557/jmr.2020.39
• Languages: English
• ISSNs: 0884-2914

Abstract

Abstract: Abstract : Recently, layered double hydroxides (LDHs) have attracted intensive research interest as the next-generation supercapacitor electrodes due to their unique two-dimensional (2D) hydrotalcite-like structure. However, the inevitable agglomeration significantly decreases the accessible surface areas and blocks the pseudocapacitive sites, thus severely hinders their electrochemical applications. Herein, we develop a facile one-step growth approach to fabricate porous agglomerate of NiCo-LDH nanosheets and reduced graphene oxide (rGO) nanoflakes. By adjusting feeding molar ratios, the obtained NiCo-LDH/rGO electrode delivers a high specific capacity of 879.5 C/g at a current density of 0.5 A/g and still remains 485 C/g at 20 A/g. Furthermore, the fabricated asymmetric supercapacitor (ASC) has demonstrated a superior energy density of 48.7 W h/kg at a power density of 401 W/kg. After 2000 cycles, the assembled ASC exhibits an improved capacity retention of 81% within a potential window of 1.6 V at 2 A/g.