Effect of processing parameters on the electrochemical performance of graphene/ nickel ferrite (G-NF) nanocomposite

Fuel cells, secondary batteries and capacitors are among many promising energy storage devices. inparticular, supercapacitors have attracted much attention because of their long life cycle and highpower density. graphene/nickel ferrite(g-nf) based supercapacitors were successfully fabricatedthrough a one-step facile solvothermal route. effects of synthesis conditions i.e. solvothermal time and temperature, on the powder particle characteristics were evaluated using x-ray photoelectronspectroscopy (xps), powder x-ray diffraction (xrd) and high-resolution transmission electronmicroscopy (hrtem). fast fourier transformation (fft) patterns were also recorded on the hrtemmicroscope to determine the lattice and crystallinity of the nanocomposites. structural and chemicalstudies proved that increasing the solvothermal duration and temperature leads to improvedcrystallinity of nife2o4phase as well as higher degree of reduction of graphene oxide to graphene. the electrochemical measurements showed that solvothermal conditions of 180°c and 10h produces the highest specific capacity of 312 and 196 f g-1 at current densities of 1 and 5 a g-1, respectively calculated from charge-discharge test. this g-nf electrode material, also showed a capacity of 105 fg-1 after 1500 cycles at current density of 10 a g-1 which makes it an outstanding supercapacitor material with promising long cycle electrochemical stability and performance.