Hexagonal sheets of Co3O4 and Co3O4-Ag for high-performance electrochemical supercapacitors

A versatile hydrothermal technique is employed to synthesize hexagonal sheets of Co3O4. Silver (Ag) nanoparticles (NPs) were decorated on the hexagonal sheets of Co3O4 by a simple chemical route. Effect of AgNPs treating time on the performance of supercapacitors is studied. [Display omitted] •Hexagonal sheets of Co3O4 electrode is synthesized by hydrothermal route.•AgNPs are decorated on Co3O4 by a simple chemical approach.•Effect of AgNPs treating time on the performance of supercapacitors is studied.•Co3O4-Ag exhibited a specific capacitance of 958Fg−1 at a scan rate of 10mVs−1.•An excellent cycling stability with a capacitance retention of 104% is observed. Hexagonal sheets of Co3O4 on nickel foam were synthesized by a facile, economical, scalable, and one pot hydrothermal method for supercapacitor studies. The electrical conductivity and catalytic activity were enhanced through the decoration of Co3O4 by silver (Ag) nanoparticles using a simple chemical approach. The hexagonal sheets served as an excellent backbone together with the Ag nanoparticles, which gave the composites a superior specific capacitance of 958Fg−1 and an energy density of 0.203kWhkg−1. The electrode exhibited excellent cycling stability with a capacitance retention of 104% after the initial 1000 CV cycles with a maximum specific capacitance 996Fg−1.