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The primary purpose of this study was to produce an ore-based high-capacity supercapacitor electrode. For this, chalcopyrite ore was first leached with nitric acid, and then metal oxide synthesis was carried out immediately on nickel foam using a hydrothermal technique from the solution. Cauliflower-patterned CuFe2O4 with a wall thickness of about 23 nm was synthesized on the Ni foam surface, characterized by XRD, FTIR, XPS, SEM, and TEM investigations. The produced electrode also displayed a feature of a battery-like charge storage mechanism with a specific capacity of 525 mF cm−2 at 2 mA cm−2 current density, energy of 8.9 mWh cm−2, and a power density of 233 mW cm−2. Additionally, even after 1350 cycles, this electrode still performed at 109% of its original capacity. The performance of this finding is 255% higher than that of the CuFe2O4 in our earlier investigation; despite being pure, it performs far better than some of its equivalents in the literature. Obtaining such performance from an electrode made from ore indicates that the use of ore has a lot of potential for supercapacitor production and property improvement. [ABSTRACT FROM AUTHOR]

The aim of this study was to synthesize CuFe 2 O 4 together with g-C 3 N 4 and GNPs in various combinations on the surface of Ni foam for use as anode materials in supercapacitors. The fabricated electrodes were investigated by XRD, FTIR, XPS, BET, SEM and TEM for content and by CV, GCD and EIS analysis for electrochemistry. The characterization results showed that CuFe 2 O 4 was successfully synthesized together with g-C 3 N 4 and GNPs in a nanosponge-like geometry. The highest value of specific capacitance was found to be 989 mF/cm2 at 2 mA measurement in the triple combination. Moreover, the stability of this electrode was measured to be 70% after 1500 cycles at 16 mA, while the energy and power densities were calculated to be 27.8 mWh/cm2 and 300 mW/cm2, respectively. The EIS results show that the carbon-based component increased the Cs value by decreasing the charge transfer and diffusion resistances of the electrodes. Compared to its counterparts in the literature, its Cs value is quite high, but its stability is low, so it can be used in low-cycle applications. [ABSTRACT FROM AUTHOR]

This study sought to determine the effect of graphene on the electrochemical performance of MgFe 2 O 4. The electrode preparation was done directly on the nickel foam surface using a hydrothermal technique. The crystallographic, morphological, and chemical configurations of the electrode components were investigated using XRD, FTIR, XPS, SEM, and TEM. Cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectrometry (EIS) were used to evaluate its electrochemical characteristics. The findings of the characterization demonstrate that MgFe 2 O 4 was successfully synthesized with GNPs in a porous structure on a Ni foam surface. The electrochemical experiments show that the greatest specific capacitance (Cs) value found is 828 mF/cm2 at 1 mA current. At the same time, its stability after 1500 cycles at 4 mA was observed to be 136%, and its energy-power densities were calculated to be 28.75 mWh/cm2 and 200 mW/cm2. The Cs value in this study is roughly 242% higher than pure MgFe 2 O 4 and 95% higher than MgFe 2 O 4 /GNPs in the literature, which is a significant effect of GNPs. • MgFe 2 O 4 /GNPs composite was synthesized by facile hydrothermal method. • MgFe 2 O 4 nanoparticles were uniformly anchored on the surface of GNPs. • Its specific capacitance value was determined as 828 mF/cm2 at 1 mA/cm2. • The performance after 1500 cycles was observed as 136% at 1 mA/cm2. • Its energy-power densities were calculated as 28.75 mWh/cm2 and 200 mW/cm2. [ABSTRACT FROM AUTHOR]