Single-step process for creating nitrogen and oxygen-enriched carbon using organic polymers for supercapacitor applications

Abstract

The growing concern over sustainable energy motivates and stimulates the production of sophisticated and portable energy storage devices like batteries and supercapacitors. The widespread use of batteries has been hampered because of their low shelf-life and power density, whereas supercapacitors are recognized to have high power density with longer cycle life. In the genre of supercapacitors, heteroatom-doped carbon materials are the most promising participants for energy-related applications. Specifically, nitrogen and oxygen-incorporated carbon materials have gained considerable progress because they can modify the carbon framework's chemical and physical properties, thereby enhancing the electrochemical performance. Nitrogen and oxygen co-doped porous carbon was synthesized through a simple one-pot reaction of the precursors (2,6-diaminopyridine and terephthalaldehyde) with KOH. The optimized material (DAPT-4-600) exhibits a specific capacitance of 339 F g⁻¹ (at 1 A g⁻¹) in 1 M H₂SO₄ and complete capacitance retention after 10,000 cycles. The enhanced electrochemical behavior of DAPT-4-600 can be attributed to its moderate surface area, pore volume, and nitrogen/oxygen functional groups. Also, when assembled in a symmetric device, DAPT-4-600 shows an energy density of 11.11 W h kg⁻¹ at a power density of 250 W kg⁻¹.