MnO2@Nickel Nanocone Arrays with High Areal Capacitance for Flexible Zincion Supercapacitor

Because of excellent power density, good reversibility, and superior stability, supercapacitors have attracted more attention in microelectronic system developments. However, the large-scale preparation of high-performance supercapacitors with low-cost and high mechanical flexibility is still challenging. Herein we report the convenient fabrication of an all-in-one pseudocapacitor by magnetron sputtering and electro-deposition of a MnO
₂
@Ni cathode and an activated carbon@Ni anode on the two sides of a glass fiber separator. Specifically, the MnO
₂
cathode deposited on Ni Nanocone arrays (NNAs) showed good cycle performance (92.2% after 5000 cycles) and excellent capacitance (644 F/g) and. The NNAs@AC (activated carbon) anode deposited on the other side showed a 224 F/g high capacitance and favorable cycle performance (105.9% after 5000 cycles). Benefiting from the special integration method, the porous architecture of the electrodes, and the use of zinc ions as the charge carrier, our all-in-one device achieved favorable mechanical flexibility, high energy density (103.4 Wh/kg at 1.7 kW/kg) with a long cycle(76% after 5000 cycles). Besides, our fabrication approach can be easily extended to the mass production of low-cost devices and provides a new alternative strategy for flexible high-performance energy storage devices.