MOFs-derived Co9S8-embedded graphene/hollow carbon spheres film with macroporous frameworks for hybrid supercapacitors with superior volumetric energy density. Issue 14 (21st March 2019)

• Record Type: Journal Article
• Authors: Niu, Haoting; Zhang, Yong; Liu, Yu; Luo, Bifu; Xin, Na; Shi, Weidong
• Is Part Of: Journal of materials chemistry. Volume 7:Issue 14(2019)
• Page Start: 8503
• Page End: 8509
• Publication Date: 2019-03-21
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c8ta11983j
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Electrode materials with macroporous structures have desirable structural advantages, which can provide excellent reaction sites for electrons and ions. Abstract : Electrode materials with macroporous structures have desirable structural advantages, which can provide excellent reaction sites for electrons and ions. In this study, a novel macroporous nanostructure is synthesized utilizing N-doped hollow carbon spheres and ZIF-67 derived Co9 S8 embedded in graphene (GH@NC@Co9 S8 ). This macroporous nanostructure can maximize the entire surface area, which provides a favorable transport environment for the electrons and ions of the electrolyte. Furthermore, in situ grown Co9 S8 polyhedra derived from ZIF-67 can improve the reactivity and specific capacity of the composite due to their amorphous phase and hollow three-dimensional structure. The as-prepared GH@NC@Co9 S8 acts as a binder-free electrode for supercapacitors; it shows a high volumetric capacitance of 842.4 F cm −3 at a current density of 1 A g −1 . An asymmetric supercapacitor fabricated with GH@NC@Co9 S8 (positive electrode) and GH@NC (negative electrode) shows a superb volumetric energy density of 28.7 W h L −1 at a high power density of 971.9 W L −1 and long cycle life (95.8% capacity retention after 8000 cycles). This device has great practical value in electrochemical energy storage.