Heteroatom-doped mesoporous carbon derived from covalent organic framework for the potential application of symmetric supercapacitor device

In the present investigation, covalent organic framework (COF) derived heteroatom-doped mesoporous carbon was prepared for the utility of supercapacitor application. Herein COF is synthesized from cost-effective precursors such as melamine and terephthaldehyde via the condensation process and its formation is confirmed by Fourier-transform infrared spectroscopy (FT-IR). The synthesized COF is then pyrolyzed from 600–1100 °C under inert atmosphere and characterized by electron microscopic, spectroscopic and electrochemical techniques. The carbonized COF at 900 °C (CCOF-900) exhibits uniform porous architecture and highest carbon and nitrogen ratio than other carbonization temperatures. Among the different pyrolysis temperatures, CCOF-900 shows uniform pore size (2.2 nm), more specific surface area (456 m² g⁻¹) and pore volume (0.73 m³ g⁻¹), which are evidenced from BET analysis. Further, it shows the highest graphitization, which is expected to facilitate the electron transfer faster. It exhibits the higher specific capacitance of 1236 F g⁻¹ @ 1 A g⁻¹ and maintains 94 % capacity retention @ 10 A g⁻¹ after 6000 charge-discharge cycles. The fabricated symmetric device also led to the achievement of a high energy density of 48 W h kg⁻¹ and power density of 450 W kg⁻¹. Finally, a red LED light powered by a symmetric supercapacitor system is demonstrated.