title: A lithographically patterned capacitor with horizontal nanowires of length 2.5 mm.
abstract: A symmetrical hybrid capacitor consisting of interdigitated, horizontal nanowires is described. Each of the 750 nanowires within the capacitor is 2.5 mm in length, consisting of a gold nanowire core (40 × ≈200 nm) encapsulated within a hemicylindrical shell of δ-phase MnO2 (thickness = 60-220 nm). These Au@δ-MnO2 nanowires are patterned onto a planar glass surface using lithographically patterned nanowire electrodeposition (LPNE). A power density of 165 kW/kg and energy density of 24 Wh/kg were obtained for a typical nanowire array in which the MnO2 shell thickness was 68 ± 8 nm. Capacitors incorporating these ultralong nanowires lost ≈10% of their capacity rapidly, during the first 20 discharge cycles, and then retained 90% of their maximum capacity for the ensuing 6000 cycles. The ability of capacitors consisting of ultralong Au@δ-MnO2 nanowires to simultaneously deliver high power and high capacity with acceptable cycle life is demonstrated.
authors.affiliation: Department of Chemistry, University of California , Irvine, California 92697-2025, United States.
authors.forename: Wenbo
authors.initials: W
authors.lastname: Yan
authors.forename: Mya Le
authors.initials: ML
authors.lastname: Thai
authors.forename: Rajen
authors.initials: R
authors.lastname: Dutta
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Li
authors.forename: Wendong
authors.initials: W
authors.lastname: Xing
authors.forename: Reginald M
authors.initials: RM
authors.lastname: Penner