Cost effective synthesis of sulfur and nitrogen co-doped graphene aerogel and application in binder free supercapacitor

• Published in: Journal of applied physics 2024-07, Vol.136 (3)
• Main Authors: Muhiuddin, Mohammad, Khan, Aliullah Zaifullah, Devi, Naorem Aruna, Bharadishettar, Naveen, Meti, Sunil, Siddique, Abu Bakar, Bhat K., Udaya, Akhtar, Waseem, Rahman, Mohammad Rizwanur
• Format: Article
• Language: English
• Subjects: Aerogels; Ammonium sulfate; Cost effectiveness; Electrical resistivity; Equipment costs; Ethylenediamine; Graphene; Low temperature; Nitrogen; Pressure; Raw materials; Reducing agents; Sulfur; Supercapacitors; Synthesis
• ISSN: 0021-8979; 1089-7550
• DOI: 10.1063/5.0202270

Incorporating heteroatoms into graphene lattice results in enhanced electrical conductivity and electrochemically active sites and has significant importance in developing high-performance supercapacitors. In this study, sulfur and nitrogen co-doped graphene aerogel is synthesized via hydrothermal technique followed by a simple but effective freeze-thawing and ambient pressure drying process (referred to as SN-GA). The process requires low-cost raw materials and cost-effective equipment without the utilization of any special instrument that operates at ultra-low temperatures, under high pressure, or vacuum environment. Ammonium sulfate [(NH4)2SO4] and ethylenediamine are used as a source of sulfur and nitrogen and as a reducing agent. (NH4)2SO4 with different molarities (0, 12, 24, and 36 mM) are used to synthesize four different aerogel samples marked as GA, SN-GA1, SN-GA2, and SN-GA3. The electrode is prepared using an SN-GA2 sample, exhibiting an outstanding specific capacitance of 244 F g−1 at an applied current density of 1 A g−1 with almost 98.5% Coulomb efficiency. Furthermore, based on the SN-GA2 sample, the symmetrical supercapacitor is fabricated, displaying an energy density of 18.14 Wh kg−1 at a power density of 498.4 W kg−1. Hence, SN-GA2 renders a promising material for supercapacitor applications.