Executive Summary : | Aqueous electrolyte-based supercapacitors are crucial energy storage technologies due to their high power density, low cost, environmental friendliness, and safety. However, their low energy density limits their widespread use. Water-in-salt electrolytes (WIS) exhibit unusual behavior, pushing the threshold of water dissociation to extend the potential window. However, WIS-based supercapacitors have lower energy density than expected due to a decrease in capacitance values. To address this issue, research is needed to develop WIS electrolyte-based supercapacitors that exhibit high energy density while maintaining high power density. The processing needs to be highly scalable and low-cost to meet commercial demand. This proposal proposes converting metal-organic-framework (MOF) into highly graphitic carbon via millisecond scale current pulse technique. This process results in a highly crystalline graphitic structure, which can be converted to highly porous morphologies through on-site activation and exfoliation. Extended potential windows, high surface area, and open porous-oriented electrodes are expected to display energy and high power density. Current-controlled heteroatom doping and suitable nano-hybridization can increase energy density further. Roll-to-roll processing of electrodes will demonstrate the practical scalability of the current pulse-induced facile technology. Low-cost supercapacitor devices based on current pulse processed electrodes in WIS electrolytes that deliver both high energy and power densities are the major outcome of this proposal. Flash-graphitization of MOF, fast current-induced exfoliation, activation, doping, and hybridization are all unique and possess high technological and scientific metrics. |