title: Enhancing the supercapacitor performance of graphene/MnO2 nanostructured electrodes by conductive wrapping.
abstract: MnO2 is considered one of the most promising pseudocapactive materials for high-performance supercapacitors given its high theoretical specific capacitance, low-cost, environmental benignity, and natural abundance. However, MnO2 electrodes often suffer from poor electronic and ionic conductivities, resulting in their limited performance in power density and cycling. Here we developed a "conductive wrapping" method to greatly improve the supercapacitor performance of graphene/MnO2-based nanostructured electrodes. By three-dimensional (3D) conductive wrapping of graphene/MnO2 nanostructures with carbon nanotubes or conducting polymer, specific capacitance of the electrodes (considering total mass of active materials) has substantially increased by ∼20% and ∼45%, respectively, with values as high as ∼380 F/g achieved. Moreover, these ternary composite electrodes have also exhibited excellent cycling performance with >95% capacitance retention over 3000 cycles. This 3D conductive wrapping approach represents an exciting direction for enhancing the device performance of metal oxide-based electrochemical supercapacitors and can be generalized for designing next-generation high-performance energy storage devices.
authors.affiliation: Department of Chemical Engineering, Stanford University , Stanford, California 94305, United States.
authors.forename: Guihua
authors.initials: G
authors.lastname: Yu
authors.forename: Liangbing
authors.initials: L
authors.lastname: Hu
authors.forename: Nian
authors.initials: N
authors.lastname: Liu
authors.forename: Huiliang
authors.initials: H
authors.lastname: Wang
authors.forename: Michael
authors.initials: M
authors.lastname: Vosgueritchian
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yang
authors.forename: Yi
authors.initials: Y
authors.lastname: Cui
authors.forename: Zhenan
authors.initials: Z
authors.lastname: Bao