Redox-active anomalous electrochemical performance of mesoporous nickel manganese sulfide nanomaterial as an anode material for supercapattery devices

In this work, we are reporting nickel manganese sulfide hierarchical redox-active nanostructured material synthesized using a facile one-step hydrothermal technique to investigate its potential for supercapattery devices. The surface morphology, crystallinity, elemental analysis/composition surface area, porosity, and homogeneity were investigated through X-ray diffraction (XRD), Energy dispersive X-ray (EDX) spectra, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Brunauer–Emmett–Teller (BET). The electrochemical characterizations were performed in a three-electrode standard cell whereas the electrolyte used was 1 M potassium hydroxide. These characterizations predict that sample S-0.4 is exhibiting superior performance over all other electrodes and therefore it was paired with activated carbon for the assembling of supercapattery (Ni–Mn–S//AC). This supercapattery was probed electrochemically with CV, GCD, EIS, and stability tests which reveals superb performance by delivering a high value of capacity (420.10 C/g) with a maximum energy density of 75.96 Wh/kg. The device was able to deliver the power density of 2865 W/kg, along with an outstanding cyclic life by sustaining 85% of capacity even after 5000 GCD cycles. Our analysis for this electrode material suggests that our synthesized material can be applied for future high-performance supercapattery devices.