Hierarchically nanostructured Zn0.76C0.24S@Co(OH)2 for high-performance hybrid supercapacitor

It is a great challenge to achieve both high specific capacity and high energy density of supercapacitors by designing and constructing hybrid electrode materials through a simple but effective process. In this paper, we proposed a hierarchically nanostructured hybrid material combining Zn0.76C0.24S (ZCS) nanoparticles and Co(OH)(2) (CH) nanosheets using a two-step hydrothermal synthesis strategy. Synergistic effects between ZCS nanoparticles and CH nanosheets result in efficient ion transports during the charge-discharge process, thus achieving a good electrochemical performance of the supercapacitor. The synthesized ZCS@CH hybrid exhibits a high specific capacity of 1152.0 C g(-1) at a current density of 0.5 A g(-1) in 2 M KOH electrolyte. Its capacity retention rate is maintained at 70.0% when the current density is changed from 1 A g(-1) to 10 A g(-1). A hybrid supercapacitor (HSC) assembled from ZCS@CH as the cathode and active carbon (AC) as the anode displays a capacitance of 155.7 F g(-1) at 0.5 A g(-1), with a remarkable cycling stability of 91.3% after 12,000cycles. Meanwhile, this HSC shows a high energy density of 62.5 Wh kg(-1) at a power density of 425.0 W kg(-1), proving that the developed ZCS@CH is a promising electrode material for energy storage applications. (C) 2022 Elsevier Inc. All rights reserved.

Automated summary

In this study, a hierarchically nanostructured hybrid material combining Zn0.76C0.24S nanoparticles and Co(OH)2 nanosheets was synthesized using a two-step hydrothermal method. The synergistic effects between ZCS nanoparticles and CH nanosheets enable efficient ion transport and result in a good electrochemical performance of the supercapacitor.