Pyrazine-based organic electrode material for high-performance supercapacitor applications

Pseudocapacitors (PCs) exhibit high capacitance and high energy density, which renders incredible execution in energy storage gadgets. PCs bridge the gap between batteries and electrostatic double-layer capacitors (EDLCs). Herein, we designed novel electrode material i.e. naphtho[2,3-h]naphtho[2′,3′:5,6]quinoxalino[2,3-a]naphtho[2′,3′:5,6]quinoxaline [2,3-c]phenazine-5,12,17,22, 27,30-hexaone (Pyz-ANQ) composed of hexaketocyclohexane (HKCH) and 2,3-diaminoanthraquione (ANQ) subunits. The Pyz-ANQ electrode has been fabricated on a Toray carbon paper (CP) and used as a pseudocapacitor electrode which showed efficient pseudocapacitor performance in a three-electrode configuration. The specific capacitance (Csp) by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) analysis are 85.2 F g−1 at a scan rate of 5 mV s−1 and 43.1 F g−1 at current density 0.5 A g−1 in 1 M H2SO4, respectively. The PCs behavior is attributed to the reversible redox chemistry of Pyz-ANQ. Furthermore, we fused the material into a symmetric solid-state two-electrode supercapacitor (SSSC) device for practical demonstration of its potential in future energy storage applications and it shows the Csp value by two methods CV and GCD such as 52.5 F g−1 @ 5 mV s−1 and 36.6 F g−1 @ 0.5 A g−1, as well as it shows excellent cyclic performance in three-electrode and two-electrode system in the percentage of 78.8% and 75.9% for 2000 GCD cycles. Significantly, Pyz-ANQ/CP electrode has an energy density of 2.6 Wh kg−1 at 4.7 kW kg−1 of power density, respectively. In this way, by utilizing HKCH and ANQ in the redox system, Pyz-ANQ/CP results in pseudocapacitive energy storage, bringing a new dimension to improve the chemistry of organic supercapacitors.