Structural microstructural and electrochemical properties of transition metal dichalcogenide materials for supercapacitor application

Abstract

The prompt growth in population and exhaustion of natural non-renewable resources newlinelike fossil fuels, coal, etc. has inspired the research community to provide a solution to newlineovercome the global energy crisis. This promoted the research in energy storage newlinedevices fields at a faster rate. Among different storage devices, the supercapacitor newline(SC) is finding its edge over others. The reasons for the same includes the SC newlinefeatures like a fast charge/discharging process, high power density, good cycle newlinestability, and low cost. These merits of SC make them suitable for application such as newlinehybrid electric vehicles. The main challenge in the research arena of supercapacitors newlineis to advance their low energy density without comprising their high value of power newlinedensity. A typical supercapacitor is comprised of components such as an electrode, newlineelectrolyte, separator, and current collector. Among all components mentioned above, newlinethe electrode material is the key element as it contributes the maximum in newlinedetermining the overall electrochemical performance of a supercapacitor. newlineBased on the outline of the structure, the SC is classified into two types: symmetric, newlineand asymmetric supercapacitors. For symmetric SC, the electrode used across the newlineseparator is of the same material while for asymmetric the electrodes are of separate newlinematerials. Whereas, based on mechanism of charge storage, the supercapacitors are newlineclassified as electric double-layer capacitors (EDLC), pseudo-capacitors and hybrid newlinesupercapacitors. The hybrid supercapacitors are depicting promising electrochemical newlinev newlineperformance over others due to which the electrode materials for the hybrid newlinesupercapacitor are explored and exercised. newlineFrom the different class of electrode material for hybrid SC, transition metal newlinedichalcogenides (TMDs) has emerged as good potential electrode material. The newlinereasons for their use in SC are their enormous surface area, variable oxidation states, newlinelow electronegativity, and high electronic conductivity (order equal to 10-3 S m-1). Pure newlineTMDs are found to sh