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This study presents a fabrication and electrochemical properties of nickel ferrite/graphene nanocomposite as electrodes material for supercapacitor application. The as‐prepared electrode was characterized using X‐ray diffraction, scanning electron microscopy, transmission electron microscopy and X‐ray photoelectron spectroscopy. The electrochemical properties were measured using cyclic voltammetry, galvanostatic charging/discharging methods and electrochemical impedance spectroscopy. Graphene nanosheets play an important role of governing the morphology of the electrode material and thereby enhancing the electrochemical performance of the composite electrode. The specific capacitance of 207 F/g is obtained for nickel ferrite/graphene nanocomposite, which is almost 4 times larger than pure nickel ferrite. The nanocomposite showed a stable capacitance of 95% after 1000 cycles in 1 M Na2SO4 electrolyte. Electrochemical impedance spectroscopy results indicate that graphene nanosheets reduced the charge transfer resistance on the composite electrode. The obtained results show that the nanocomposite has a great potential to be used in supercapacitor with good electrochemical performance and longer cycle stability. [ABSTRACT FROM AUTHOR]

We report here the effect of a controlled modification of the shell microstructure around the crystalline core of a silicon nanowire (SiNW) grown at a low (320 °C) temperature by the hot wire chemical vapor processing (HWCVP) method. We demonstrate these effects through the evaluation of the performance of a micro-supercapacitor (µ-SC) device fabricated with these SiNWs having different shell structures. It is to be emphasized that the shell microstructure could be modified through a controlled interplay of the process parameters during the growth. A careful optimization of the shell microstructure in these nanowires during its low-temperature deposition has led to a µ-SC with capacitance value of 94 µF/cm. This result opens up exciting opportunities for HWCVP-grown SiNWs to be employed for on-chip µ-SC and other low-temperature applications. [ABSTRACT FROM AUTHOR]