3D Nanosheet-Assembled CoSe Quasi-Microspheres as Advanced Electrode Materials for Electrochemical Energy Storage. Issue 12 (9th August 2017)

• Record Type: Journal Article
• Authors: Zhu, Yirong; Chen, Xianhong; Chen, Han; Ji, Xiaobo; Liu, Yong
• Is Part Of: Journal of the Electrochemical Society. Volume 164:Issue 12(2017)
• Page Start: A2341
• Page End: A2347
• Publication Date: 2017-08-09
• Subjects: 3D -- asymmetric supercapacitors -- CoSe -- electrochemistry -- quasi-microspheres; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0621712jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : Metal selenides, as a new class of metal chalcogenide, have recently attracted researcher's attention as superior electrode materials for energy storage. In this work, we have prepared the 3D nanosheet-assembled CoSe quasi-microspheres by a facile hydrothermal synthesis route and utilize them as supercapacitor electrode materials for the first time. The resulting 3D nanosheet-assembled CoSe quasi-microspheres manifest superior capacitive properties with a high specific capacitance of 440 F g −1 at 1 A g −1, excellent capacity retention rate of 85.9, 56.4 and 41.4% at 10, 50 and 100 A g −1, and good cycling stability with 102.3 and 96.3% of initial capacity retention rate at 2 and 10 A g −1 over 2000 and 5000 cycles, respectively. The good electrochemical performances can be ascribed to the unique 3D micro-/nanostructure with superior pore-size distribution, relatively large mesopores and exceptional electrical conductivity. The asymmetric supercapacitor is further assembled by employing 3D nanosheet-assembled CoSe quasi-microspheres as the cathode and activated carbon (AC) as the anode, respectively. The CoSe/AC asymmetric device displays a energy density of 17.6 Wh kg −1 at a power density of 684 W kg −1, and maintains 95.5% of its initial capacity at 3 A g −1 over 2000 cycles.