▎ 摘　　要

Among various energy storage devices, supercapatteries are notable for delivering significant electrochemical performance in terms of high specific power and specific energy. Herein, a sonochemical approach was utilized to synthesize the cobalt phosphate (Co-3(PO4)(2)) for utilization as an electrode material for supercapattery device. To tune the electrochemical performance via enhancement of ionic conduction, composites of Co-3(PO4)(2) along with reduced graphene oxide (rGO) powder at different wt% were made. The optimum electrochemical performance was delivered by the composite containing 85% Co-3(PO4)(2) and 15% rGO profits a maximum Q(s) of 619.2 C/g at 3 mV/s, and 415.6 C/g (specific capacitance of 593.2 F/g) at 2.0 A/g. In a supercapattery device, the prime electrochemical performer was utilized as the positive and activated carbon as a negative electrode. Our supercapattery device delivered remarkable specific energy of 68.06 Wh/kg and carries a tremendous maximum specific power of 7650 W/kg along with 98.03% of capacity retention observed after the 2000 continuous GCD cycles. The device shows a capacitive contribution of 13.61%, 24.25%, and 39.69% at 10, 50, and 100 mV/s correspondingly calculated through simulation approach. The research demonstrates an aim to tune the electrochemical capability of Co-3(PO4)(2) for potential electrochemical devices. Highlights center dot Cobalt phosphate is synthesized by sonochemical approach. center dot Composition of cobalt phosphate and reduced graphene oxide was optimized. center dot High specific capacity of 415.6 C/g was obtained via composition containing 85% Co-3(PO4)(2) and 15% rGO. center dot Supercapattery formed by coupling this composite with activated carbon. center dot High power density of 7650 W/kg and high energy density of 68.06 Wh/kg. center dot Specific capacity retention of 98.03% after continuous 2000 GCD cycles.