Fabrication of Co3O4 from Cobalt/2,6-Napthalenedicarboxylic Acid Metal-Organic Framework as Electrode for Supercapacitor Application

Abstract

In this study, cobalt-based metal-organic framework (MOF) powder was prepared via the solvothermal method using 2,6-naphthalenedicarboxylic acid (NDC) as the organic linker and N,N-dimethylformamide (DMF) as the solvent. The thermal decomposition of the pristine cobalt-based MOF sample (CN-R) was identified using a thermogravimetric examination (TGA). The morphology and structure of the MOFs were modified during the pyrolysis process at three different temperatures: 300, 400, and 500 °C, which labeled as CN-300, CN-400, and CN-500, respectively. The results were evidenced via field-emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The crystallite size of all samples was calculated using Scherrer’s equation. The smallest crystallite size of 7.77 nm was calculated for the CN-300 sample. Fourier transform infrared spectroscopy (FTIR) spectra were acquired for all the samples. The graphical study of the cyclic voltammogram (CV) gave the reduction and oxidation peaks. The charge transfer resistance and ionic conductivity were studied using electrical impedance spectroscopy (EIS). The galvanostatic charge–discharge (GCD) responses of all samples were analyzed. The relatively high specific capacitance of 229 F g−1 at 0.5 A g−1 was achieved in the sample CN-300, whereby 110% of capacitance was retained after 5000 cycles. These findings highlighted the durability of the electrode materials at high current densities over a long cycle.

Flexible Supercapacitors Based on Graphene/Boron Nitride Nanosheets Electrodes and PVA/PEI Gel Electrolytes

“…The electrochemical impedance (EIS) behavior of the WSCs was then studied (Figure 4h). G/BNNS@H shows a much smaller intercept with the x-axis than that of G@H (47.76 ohm/cm 2 vs. 63.26 ohm/cm 2 ), which means that G/BNNS@H has the lower equivalent series resistance (ESR) than that of G@H [31]. The smaller semicircle of G/BNNS@H in the middle frequency regions hints at a lower electron/ion chargetransfer resistance.…”

Electrical Response of the Spinel ZnAl2O4 and Its Application in the Detection of Propane Gas

“…In our case, all the diffractograms' reflections were considered, obtaining an average crystal size of ~14.63 nm. Considering Figure 1, the crystal size t was calculated with Scherrer's equation [22]:…”

Morphology-controlled synthesis of MoS2using citric acid as a complexing agent and self-assembly inducer for high electrochemical performance

“…To date, a number of materials have been developed for use as electrode materials in supercapacitors. 4–8…”