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It's crucial to fabricate commercial-level electrodes with high mass loading of active materials for supercapacitors (SCs) to address the growing need for commercial-level flexible energy storage devices. In this work, we reported the direct growth of ZnCo2O4 nanonest-like structure composed of nanowires with high mass loading (5 mg cm−2) on the substrate of carbon cloth (CC, hereafter denoted as ZnCo2O4@CC) via a simple hydrothermal method. The ZnCo2O4@CC electrode was characterized by a variety of techniques including SEM/TEM, XRD/XPS, and BET/BJH. The ZnCo2O4@CC electrode possesses a holey characteristic with various electroactive sites for the utilization of electrolyte and delivered high specific capacitance of 1467 (1320 C g-1) Fg−1 at 1.2 Ag-1 with outstanding cycling retention of 95% at 12 Ag-1 and high Coulombic efficiency after 10,000 cycles. In addition, we employed power's law to explore the charge storage kinetics of ZnCo2O4@CC electrode to investigate the capacitive and diffusion-controlled charge storage quantification. The ZnCo2O4@CC electrode displayed high capacitive storage properties (42% capacitive at 15 mVs−1). Thus, the admirable electrochemical performance of the ZnCo2O4 electrode highlights the potential application in supercapacitors for future endowers.

In this work, iron oxide (Fe3O4) nanodiscs and anchored on reduced graphene oxide (rGO) as a nanocomposite (Fe3O4/rGO) have been fabricated through a surface, scalable hydrothermal process. The morphological and structural studies of Fe3O4/rGO nanodiscs are analyzed by various techniques such as XRD, XPS, SEM, TEM, and TGA, etc. The Fe3O4/rGO electrode is tested as a negative electrode in a basic potassium hydroxide (KOH) electrolyte using a three-electrode system for supercapacitor applications. The optimized electrochemical properties of Fe3O4/rGO are systematically compared with bare Fe3O4 and it is found that the rGO greatly enhanced its performance as a negative electrode. The Fe3O4/rGO nanodiscs demonstrated a notably high-specific capacitance of 1149 F/g at 1.5 A/g better than that of Fe3O4 nanodiscs (920 F/g at 1.5 A/g). Furthermore, the Fe3O4/rGO displays the superior cyclic stability of 97.53% after running continuous 10000 GCD cycles at a high current density of 10 A/g, while bare Fe3O4 attained 87.82% at identical conditions. The fascinating electrochemical performance can be benefited for future fabrications of iron graphene-based negative electrode material for SCs.