Abstract
While the synthesis of hollow structures of transition metal oxides is well established, it is extremely challenging to fabricate complex hollow structures for mixed transition metal sulfides. Here we report an anion exchange method to synthesize a complex ternary metal sulfides hollow structure, namely nickel cobalt sulfide ball-in-ball hollow spheres. Uniform nickel cobalt glycerate solid spheres are first synthesized as the precursor and subsequently chemically transformed into nickel cobalt sulfide ball-in-ball hollow spheres. When used as electrode materials for electrochemical capacitors, these nickel cobalt sulfide hollow spheres deliver a specific capacitance of 1,036 F g(-1) at a current density of 1.0 A g(-1). An asymmetric supercapacitor based on these ball-in-ball structures shows long-term cycling performance with a high energy density of 42.3 Wh kg(-1) at a power density of 476 W kg(-1), suggesting their potential application in high-performance electrochemical capacitors.
Highlights
While the synthesis of hollow structures of transition metal oxides is well established, it is extremely challenging to fabricate complex hollow structures for mixed transition metal sulfides
Wang et al.[29] synthesized multishelled Co3O4 hollow microspheres with carbonaceous microspheres as hard templates, which exhibit higher lithium storage capacity and improved cycling performance compared with single-shelled Co3O4 microspheres
Ternary nickel cobalt sulfides have been regarded as a promising class of electrode materials for high-performance energy storage devices, since they offer higher electrochemical activity and higher capacity than mono-metal sulfides[36,37,38,39]
Summary
While the synthesis of hollow structures of transition metal oxides is well established, it is extremely challenging to fabricate complex hollow structures for mixed transition metal sulfides. We report an anion exchange method to synthesize a complex ternary metal sulfides hollow structure, namely nickel cobalt sulfide ball-in-ball hollow spheres. An asymmetric supercapacitor based on these ball-in-ball structures shows long-term cycling performance with a high energy density of 42.3 Wh kg À 1 at a power density of 476 W kg À 1, suggesting their potential application in high-performance electrochemical capacitors Owing to their unique structural features and intriguing properties, hollow micro-/nanostructures with tunable size, shape, composition and interior architecture have attracted growing research interests for various applications, such as energy storage, catalysis, chemical sensors and biomedicine[1,2,3,4,5,6,7,8]. When used as electrode materials for electrochemical capacitors, the NiCo2S4 ball-in-ball hollow spheres deliver excellent pseudocapacitve performance with high specific capacitance and remarkable rate capability
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
