Engineered 2D Boron Nitride Flexible Electrodes for Supercapacitors

Supercapacitors present a substantial surge forward in renewable energy storage technology. Their remarkable power density and rapid charge and discharge capabilities outstrip those of traditional batteries, opening up exciting possibilities for storing renewable energy from intermittent solar and wind power sources. So far, high power density devices have been accomplished by combining electric double-layer capacitors (EDLC) with pseudocapacitors such as polyaniline (PANI). We introduce 2D heterojunction hybrid supercapacitors integrating iron-doped boron nitride (Fe-BN) electrodes with PANI. This Fe-BN/PANI hybrid shows excellent stability under mechanical, thermal, and electrochemical stresses and forms a flexible, high-efficiency supercapacitor. The capacitance of the hybrid 2D device is 721 F g –1 at 1 A g –1 current density in a three-electrode setup. A two-electrode symmetric cell assembly prepared using this hybrid system demonstrates energy and power densities of 15.25 Wh kg –1 and 1000 W kg –1 at 2 A g –1 current density. Notably, the symmetric cell retains 81% of its specific capacitance after 10000 charging–discharging cycles at 10 A g –1, highlighting its potential as a durable and efficient electrode material for supercapacitors.