Specific capacitance, energy and power density coherence in electrochemically synthesized polyaniline-nickel oxide hybrid electrode

In the present manuscript, polyaniline (PAni), nickel oxide (NiO), and a fine nanosheet-type network of PAni-NiO hybrid film electrodes are prepared using electrodeposition technique and envisaged as electrode materials in electrochemical capacitor application. Furthermore, these film electrodes are characterized for their structural and morphological studies with the help of X-ray diffraction and scanning electron microscopy measurements, respectively. Atomic force microscopy revelation affords the roughnesses of electrode surfaces. Contact angle elucidation explodes the hydrophilic nature of PAni, NiO and PAni-NiO hybrid electrode surfaces. Electrochemical measurements confirm that the PAni-NiO hybrid electrode shows synergic effect as its specific capacitance measured at a scan rate of 5 mV/s in 1 M Na₂SO₄ electrolyte is noticeably higher (936.36 F/g) than the PAni and NiO electrodes (601 and 263.5 F/g). All these electrodes exhibit remarkable capacity retention performance after 2000 cycles. The nanosheet network of PAni-NiO hybrid electrode offer a great reaction surface area for rapid ion and electron transfer with good stability as well, which all are advantageous for enhancing the electrochemical capacitance performance.