Hydrolysis of metal-organic framework towards three-dimensional nickel cobalt-layered double hydroxide for high performance supercapacitors. (October 2020)

• Record Type: Journal Article
• Authors: Xue, Xiaolei; Zhong, Jinyan; Liu, Jianhua; Hou, Zhifeng; Wu, Xueke; Li, Songmei; Yu, Mei
• Is Part Of: Journal of energy storage. Volume 31(2020)
• Publication Date: 2020-10
• Subjects: In-situ hydrolysis -- 3D NiCo layered double hydroxide -- Metal-organic framework -- Supercapacitor; Energy storage -- Periodicals; Energy storage -- Research -- Periodicals; 621.3126
• DOI: 10.1016/j.est.2020.101649
• Languages: English
• ISSNs: 2352-152X

Abstract

Highlights: NiCo-LDH/CFC was synthesized by in-situ hydrolysis conversion of MOF. 3D nanostructure increased electroactive sites. The NiCo-LDH/CFC exhibited excellent electrochemical properties. Hybrid supercapacitors were assembled and delivered a high specific capacitance. Abstract: Layered double hydroxide (LDH) is commonly employed as supercapacitor electrode due to its high theoretical and experimental capacitance, but limited by its easily agglomerated structure. Herein, a three-dimensional nickel cobalt-layered double hydroxide on carbon fiber cloth (NiCo-LDH/CFC) is synthesized via an in-situ hydrolysis of Co-based metal organic framework array (Co-MOF) for supercapacitors. Both the metal sites and overall morphology of Co-MOF are well maintained inner NiCo-LDH/CFC, providing sufficient active sites and rapid diffusion kinetics for charge storage. Consequently, an optimal specific capacitance of 2685 F g −1 (1074 C g −1 ) is achieved for NiCo-LDH/CFC electrode, higher than that of powdered NiCo-LDH (1352 F g −1 or 540.8 C g −1 ). Moreover, a hybrid supercapacitor is assembled with NiCo-LDH/CFC as positive electrode and active carbon as negative electrode. The hybrid device exhibits a high energy density of 64.9 Wh kg −1, a maximum power density of 16.9 kW kg −1, and long cycling stability (82.7% capacitance retention after 3000 cycles). These results indicate the great potential of in-situ hydrolysis of MOFs for high performance energy storage electrode materials.