Design and fabrication of bimetallic oxide nanonest-like structure/carbon cloth composite electrode for supercapacitors

Abstract 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.