Boron–Carbon-Nitride (BCN) Coated Conducting Carbon Cloth for High-Performance Free-Standing Solid-State Supercapacitor

The dynamic growth of free-standing electrodes has played a key role in wearable electronics and portable technologies. To meet this demand, our present research introduces a flexible energy storage solution using Boron–Carbon-Nitride (BCN) coated carbon cloth (CC@BCN) as the free-standing electrode material for supercapacitors. The CC@BCN delivered a high areal capacitance of 2384 mF cm –2 at a current density of 4 mA cm –2 in a two-electrode configuration using 1 M H 2 SO 4 liquid electrolyte. The electrode exhibited a maximum areal energy density of 0.331 mWh cm –2 and a power density of 9.996 mW cm –2, along with excellent cycling stability by retaining 98.3% of its initial capacitance after 10,000 charge–discharge cycles at 10 mA cm –2 . The electrode also shows promising performance as a solid-state supercapacitor using a PVA-H 3 PO 4 gel electrolyte, and the assembled solid-state device achieved a specific capacitance of 202 mF cm –2 at 2 mA cm –2 . Furthermore, it maintains 87.5% of the capacitance retention value after 5000 cycles at 3 mA cm –2 . This approach provides a scalable as well as effective pathway to develop robust electrode materials for wearable devices that could be used in next-generation energy storage devices.