## 3 Results and Discussion
### Electrochemical Performance of CSLDH Electrode
Contrasting with the linear charge-discharge curves which are characteristics of EDLC, the prominent plateau was observed in the discharge curves, which confirmed the faradic reaction for all three electrodes that again confirms that the capacitance is achieved predominantly from the faradic reaction mechanism and thus is in good agreement with CV observation. To further examine the electrochemical behavior,  
the charge-discharge analysis was performed at various current densities from 1-7 Ag\({}^{-1}\). All the electrodes show a semi-symmetric CD curve which demonstrates rapid response and excellent electrochemical reversibility and confirms the faraic behavior of the electrodes [41; 42]. The CSLDH-2 electrode shows higher CD time over the entire range of current density as compared to the other two electrodes. These findings are well matched with the results from the CV analysis. The obtained charge-discharge results were further applied to determine the specific capacitance values using following equation:  
\[\text{C}=\text{I}\times\Delta\text{t}/\Delta\text{V}\times\text{w}, \tag{2}\]  
where C is the specific capacitance, I is stand for the discharge current density, \(\Delta\)t is the charge-discharge time, \(\Delta\)V is the working potential window, and w is the mass of active material which present on the current collector. The calculated specific capacitance of the CSLDH-2 electrode is 658 Fg\({}^{-1}\) at current density of 1 Ag\({}^{-1}\) which is higher than CSHDS (520 Fg\({}^{-1}\)) and CSLDH-1 (434 Fg\({}^{-1}\)) electrodes. The higher specific capacitance of the CSLDH-2 electrode is due to the nanosize of the fibrous morphology. Figure 12d represents the CD curves of the CSLDH-2 electrode, whereas Figures 12c and 11b show the CD curves of the CSLDH-1 and CSHDS electrodes, respectively, at current densities ranging from 1 Ag\({}^{-1}\) to 7 Ag\({}^{-1}\). The calculated specific capacitance of the CSLDH-1 and CSHDS electrodes at different current densities of 1, 2, 3, 4, 5 and 7 Ag\({}^{-1}\) were 658, 584, 330, 312, 290, 280 Fg\({}^{-1}\), respectively. For the CSLDH-1 electrode, the estimated specific capacitances were 520, 444, 300, 176, 120, 98 Fg\({}^{-1}\). Similarly, the specific capacitances of CSHDS electrode were 434, 312, 210, 96, 57, 42 Fg\({}^{-1}\), respectively. Among all three of the electrodes, CSLDH-2 electrode exhibited higher specific capacitance because of its nanofibrous morphology, which provides higher surface area and more active sites for the electrolyte intercalation-deintercalation during the CD process and maximizes the utilization of the CSLDH-2 electrode. Figure 13a represents the specific capacitance of the CSHDS, CSLDH-1 and CSLDH-2 at different current densities. From Figure 13a, it is clearly demonstrated that with an increase in the current densities, the specific capacitance decreased for all three electrodes. The highest specific capacitance (e.g., 658 Fg\({}^{-1}\) at 1 Ag\({}^{-1}\) current density) was observed in the complete range of current density with an electrode prepared by an optimal percentage/quantity of the precursor, which is a CSLDH-2 electrode. Moreover, the specific capacitance slowly decreased with an increase in the operating current density, and then demonstrated steeper drops including the other two electrodes. This is due to low intercalation of the electrolyte ions into the bulk of the electrode, which then does not have much time to take a part in the reaction with the electrolyte at a higher current density. The specific capacitance of the nanofibrous CSLDH-2 electrode is higher than the previously reported cobalt-tin composite electrodes. For example, nanoparticle of CoSn(OH)\({}_{6}\) showed higher specific capacitance of 450 Fg\({}^{-1}\), and the SnO\({}_{2}\)/Co\({}_{3}\)O\({}_{4}\)-C composite exhibited higher specific capacitance of 177 Fg\({}^{-1}\)[43; 44]. The comparative performances, including the different concentrations of the electrolytes [45; 46; 47; 48; 49], are also summarized in Table 2.