Construction of hierarchical nickel cobalt sulfide@manganese oxide nanoarrays@nanosheets <scp>core‐shell</scp> electrodes for high‐performance electrochemical asymmetric supercapacitor
Vinayak G. Parale, Taehee Kim, Amar M. Patil, Varsha D. Phadtare, Haryeong Choi, Rushikesh P. Dhavale, Younghun Kim, Seong Chan Jun, Hyung‐Ho Park
Abstract
Core-shell nanostructured three-dimensional binderless electrode porosity makes them ideal candidates for electrochemical energy storage applications. This article proposes NiCo2S4@MnOx electrodes fabricated using a facile hydrothermal approach and subsequently annealed at 120°C for 12 hours. The resultant [email protected] structure allows rapid ion and electron transport. Coating with pseudocapacitive MnOx on NiCo2S4 nanoarrays improves overall capacitance, and the amorphous MnOx nanosheets promote electrode cycling stability. The proposed NiCo2S4@MnOx electrode achieved excellent specific capacitance of 1640 F·g−1 at 5 mA·cm−2 and cyclic stability ≈ 90%; and the subsequently fabricated asymmetric electrochemical supercapacitor achieved specific capacitance ~96.91 F·g−1, and specific energy (SE) 26.38 Wh·kg−1 at specific power (SP) 466.66 W·kg−1, with impressive electrochemical stability ≈ 80% over 5000 charge/discharge cycles.