Designing of high performance MoS₂@VZnS//AC hybrid battery supercapacitor device for the electrochemical energy storage and glucose detection

Abstract

Due to their high conductive properties and superior specific capacitance, metal sulfides exhibit remarkable electrical conductivity. Transition metal dichalcogenides (TMDs) are regarded ideal options for energy harvesting devices due to their unique 2D arrangement and remarkable electrochemical properties. In this work, the typical exfoliation method (tip sonication method) was used to synthesize the molybdenum disulfide (MoS2). By using the hydrothermal method, the vanadium zinc sulfide is synthesized. The composite was analyzed through SEM, XRD, and XPS techniques to comprehensively investigate its morphological, structural, and compositional characteristics. The MoS2@VZnS electrode achieved a specific capacity (Qs) of 1025 Cg-1 at 3 mVs-1 after being tested in 1 M KOH. In a two-electrode set-up, activated carbon is used as a negative electrode, and MoS2@VZnS is used as a positive electrode for the fabrication of a hybrid supercapacitor. The asymmetric device has demonstrated a Qs of 285.4 Cg-1 at 1.4 Ag-1. The fabricated asymmetric supercapacitor device has manifested an excellent energy density (Ed) of 39.5 Whkg-1 and power density (Pd) of 2462.35 Wkg-1. Furthermore, in the durability test of MoS2@VZnS//AC, it exhibited an impressive capacity retention of 91.32% after enduring 5,000 cycles. Besides this, an investigation was conducted on a glucose electrochemical sensor utilizing MoS2@VZnS, to enhance its performance. The device showed extraordinary performance and large sensitivity against glucose even up to a very high value. The multifunctional MoS2@VZnS nanocomposite electrode material provides new opportunities to design hybrid devices in energy storage devices and biomedical applications.