Hydrothermal synthesis of Cu2S/NiS/Ni3S4 as high performance supercapacitor application
Arkapriya Das, Anirban Maitra, Ankita Mondal, Anurima De, Parna Maity, Bhanu Bhusan Khatua
Abstract
The depletion of natural energy resources on a global scale necessitates the development of specialized devices for storage and conversion of electrical energy. Transition metal sulfides are one of the potential candidates for supercapacitor and electrocatalyst applications. Herein, we present the preparation of Cu 2 S/NiS/Ni 3 S 4 by a single-step and green hydrothermal synthesis approach, which is both cost-effective and environment friendly in nature. The XRD result confirms the formation of a mixed phase comprehending cubic Ni 3 S 4 and rhombohedral NiS along with Cu 2 S. The BET measurement provides a surface area of 13.186 m 2 g −1 which further boosts the electrochemical activity. The pivotal reason for its excellent electrochemical properties is its synergistically enhanced behaviour that helps in faster electron transfer , efficient reactions in electrode-electrolyte interface and obtaining wide potential window of 1.4 V. It exhibits a specific capacity of 363.05 mAh g −1 at 0.5 A g −1 , and an impressive retention capacitance of 94.8 % over 8000 cycles. The as-designed asymmetric hybrid supercapacitor device delivers a specific capacity of 55.07 mAh g −1 at 1 A g −1 , followed by an ample energy density of 41.52 Wh kg −1 at 1 A g −1 and a notable high power density of 15,017 W kg −1 at 20 A g −1 .