G-C3N4/WO3(H2O)0.33 nanostructured electrode for hybrid asymmetric-supercapacitor

Abstract

The demand for high-energy storage supercapacitors with appropriate designs has been emerging in recent times. Aimed at enhancing the electrochemical storage performance of supercapacitors, g-C3N4/WO3(H2O)0.33 (GCN/WO) nanostructures have been prepared in a simple wet impregnation process by mixing the synthesized g-C3N4, and WO3(H2O)0.33 materials and their performances were compared systematically with their individual components. The successful formation of C3N4/WO3(H2O)0.33 nanostructure has been confirmed by the XRD, SEM, EDS, HR-TEM, HAADF and XPS spectroscopy analyses. The prepared GCN/WO nanostructures showed greater specific capacitance of 466.88C g−1 at 1.5 A g−1 than their counterparts (GCN 87.87C g−1 and WO 140.64C g−1) with remarkable cyclic stability of 98.6% over 10000 cycles. Notably, the fabricated hybrid asymmetric supercapacitor devices (HASDs) exhibited ultrahigh power density of 255.23 W kg−1 at energy density of 10.07 Wh kg−1. The enhanced electrochemical capacitor characteristics of GCN/WO nanostructures could be attributed to the positive synergistic effect of GCN and WO. Thus, the strategy utilizing this synergistic effect between GCN and WO in a simple impregnation process is a viable alternative to fabricate the high capacitance electrodes for application in supercapacitors.