Enhancing the charge transfer and redox characteristics in energy storage devices with a layered ZnNbS@graphene nanocomposite electrode material for biomedical application

Abstract

Hybrid supercapacitors, a type of device that integrates the functionalities of both supercapacitors and batteries, exhibit significantly enhanced power and energy densities. Two-dimensional materials particularly graphene with remarkable characteristics such as conductivity, sensitivity, and storage capacity, have garnered significant attention in the realm of energy storage. Herein, a composite electrode of zinc niobium sulfide (ZnNbS) and graphene (Gr) is designed and measured the electrochemical and biomedical applications. The composite electrode ZnNbS@Gr (75/25 ratio) showed a high value of specific capacity of 1573.01 Cg−1, much better than pristine ZnNbS (854.32Cg−1) because of the improvement in charge transfer and redox characteristics. Further, a hybrid supercapacitor device (ZnNbS@graphene//AC) is designed and achieves a specific capacity (179.2 C/g) at 1.5 A/g. The energy density is establish 42.1 WhKg−1, whereas the power density is 2500 WKg−1. This device is measured up to 5000 charging and discharging cycles, obtained a high value of capacity recantation of 96 %. Besides, this device is used to accurately detect the glucose to a small amount of 0.01 mM. The conclusions of our investigation provide a remarkable beginning for the advancement of high-capacity energy storage systems and biomedical applications.