Synergistic effect in g-C3N4/CuO nanohybrid structures as efficient electrode material for supercapacitor applications

A facile thermal decomposition and hydrothermal techniques were used to fabricate g-C3N4/CuO nanohybrid electrode material. The pure g-C3N4, CuO and g-C3N4/CuO nanohybrid composites were confirmed by powder X-ray diffraction (XRD), high-resolution scanning electron microscopy (HRSEM) and Fourier-transform infrared spectroscopy (FTIR). The g-C3N4/CuO electrode material exhibited a specific capacitance of 98F/g which is substantially higher than those using bare CuO (40F/g) and bare g-C3N4 electrodes (62F/g). Cycle-life data for over 2500 cycles reflect 19 % capacitance degradation for g-C3N4/CuO nanohybrid material. The energy density given by g-C3N4/CuO, CuO and g-C3N4 devices is 14.8 W h kg-1, 5 W h kg-1 and 6.3 W h kg-1 respectively. The enhanced electrochemical performance of the nanohybrid material is ascribed to synergistic effect and pseudo capacitive nature of the metal oxide nanoparticles incorporated in the g-C3N4 matrix.