title: Three-dimensional cobalt oxide microstructures with brush-like morphology via surfactant-dependent assembly.
abstract: In this study, three-dimensional cobalt oxide microstructures were developed. Cobalt oxide microdumbbells and microspheres, assembled by nanowires and primary particles, were successfully synthesized by a multistep hydrothermal method. Of all of the structures, the cobalt oxide microdumbbell electrode possesses the largest surface area of 70.8 m(2) g(-1) and the highest specific capacitance of 407.5 F g(-1). The as-prepared electrode also demonstrates excellent electrochemical stability and retains 97.5% of the initial capacitance after 2000 charge-discharge cycles. This performance is attributed to the desirable morphology, uniform microarchitecture stability, and high surface area. The results show that the as-fabricated Co3O4 is a promising electrode material for supercapacitor applications.
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637459, Singapore.
authors.forename: Duc Tai
authors.initials: DT
authors.lastname: Dam
authors.forename: Jong-Min
authors.initials: JM
authors.lastname: Lee
keywords: cobalt oxide; electrochemical; hexanitrocobaltate; hydrothermal; microdumbbell; supercapacitor