A dual NiCo metal-organic frameworks derived NiCo2S4 core-shell nanorod arrays as high-performance electrodes for asymmetric supercapacitors

The structural stability of electrode materials is the crux of significantly improve the electrochemical per-formance of pseudocapacitor electrodes. Herein, we demonstrate the preparation of NiCo2S4 with core-shell and micro-porous structure on nickel foam as an efficient anode material for asymmetric superca-pacitor (ASC) via hydrothermal and co-sulfurization processes. The NiCo2S4 electrode shows a remarkable specific capacitance of 850.2 C g(-1) at 1 A g(-1), and retains 93.6 % original capacitance after 5000 cycles. Furthermore, the NiCo2S4 electrode also have excellent electrochemical performance when used as an anode of asymmetric NiCo2S4//Active Carbon (AC) supercapacitor, which generates an energy density as 38.1Wh Kg(-1) at 700 W kg(-1) and 84.3% capacity retention after 5000 cycles. This work provide an effi-ciently method to suppress volume expansion during sulfuration reaction by core-shell structure, which potential application in transition metal sulfides electrode materials in electrochemical energy storage and conversion devices. (C) 2021 Elsevier Ltd. All rights reserved.