High-performance asymmetric supercapacitors utilizing manganese oxide nanoparticles grafted graphitic carbon nitride nanosheets as the cathode and hypercross-linked polymer derived activated carbon as the anode

• Published in: Diamond and related materials 2023-06, Vol.136, p.110005, Article 110005
• Main Authors: de Souza dos Santos, Raphael, Babu, Rajendran Suresh, Vinodh, Rajangam, Samyn, Leandro Marques, Pollet, Bruno G., Olivera, Fabian, de Barros, Ana Lucia Ferreira
• Format: Article
• Language: English
• Subjects: Energy storage; Graphitic carbon nitride; Manganese oxide; Porous carbon; Supercapacitors
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2023.110005

Herein, we demonstrated the inexpensive construction of a high-performance asymmetric supercapacitor (ASC) that was combined with manganese oxide nanoparticles grafted graphitic carbon nitride nanosheets (Mn3O4@GCN-NS) as the cathode and nitrogen doped hypercross-linked polymer derived activated carbon (NHCP-AC) as the anode with 6.0 M aqueous KOH electrolyte. In the beginning, Mn3O4@GCN-NS was successfully prepared via a single-step pyrolysis assisted method and the NHCP-AC was synthesized via Friedel-Crafts reaction. The as-synthesized nanocomposites exhibited higher specific capacitance of 436.2 at 0.5 A g−1 in three-electrode cell configuration. Furthermore, the ASC device was fabricated by integrating Mn3O4@GCN-NS with NHCP-AC, which demonstrated considerable energy density of 22.2 Wh/kg at 400 W/kg power density together with remarkable cyclability (93.5 % capacitive retention even after 5000 cycles of charge and discharge). The light emitting diode (5 mm dia.) was powered for about 15 min using two ASC devices coupled in series, demonstrating the effectiveness of its power source. Thus, the results demonstrated that the ASC devices have enormous potential for investigating cutting-edge applications in the field of advanced energy storage. [Display omitted] •Single step pyrolysis method towards the preparation of Mn3O4@GCN-NS•NHCP-AC was synthesized via Friedel-Crafts reaction.•ASC exhibits high specific capacitance of 249 F g−1 at 0.5 A g−1.•ASC shows good stability with capacitance retention of 93.5 % after 5000 cycles.