Augmenting the electrochemical capability of TMDCs thin film electrodes via interface engineering for energy storage applications

Low power density and low energy density associated with traditional devices, such as batteries, and supercapacitors led to the development of hybrid supercapacitors (HSCs). Researchers explore various classes of materials to cope with these limitations. Among them, transition metal dichalcogenides (TMDCs), due to their layered structure, are widely analyzed. Here the sputtering route was adopted to deposit a uniform interfacial layer of zirconium nitride (ZrN) 100 nm, which plays a crucial role in modulating the electrochemical properties of the top sputtered tungsten disulfide (WS₂) layer of 250 nm. The electrochemical measurements resulted the specific capacitance of 858F/g for WS2 and 2036F/g for WS₂/ZrN at scan rate of 3 mV/s. Hybrid device WS₂/ZrN//AC exhibited an energy density of 76 Wh/kg, and a power density of 4325 W/kg. In addition to this, a semiempirical approach is adopted to deconvolute capacitive and diffusive contributions. This hybrid structure can improve charge storage capacity, stability, and cycle life, making it a promising material for next-generation energy storage solutions.