摘要
In this work, the composite papers, containing carbon nanotubes (CNTs) and nickel oxides, possess high specific capacitance because of the formation of synergistic effect by adopting a conductive CNT network structure as the supporting architecture and nickel oxide as the primary material of the supercapacitor. The presence of CNT network improves the poor electrical conductivity of the nickel oxides and benefits the electron transfer during the charge/discharge processes, as a result, achieves a high specific capacitance. The CNT/NiO hybrids are synthesized via hydrothermal treatment and subsequently mixed with different amounts of pristine CNTs during the filtration process to form multilayered CNT/NiO hybrid paper electrodes, which possess a stable lamellar structure without binder. The hybrid paper electrode shows a high specific capacitance of 713.9 F/g at a scan rate of 2 mV/s. By paring the as-fabricated paper electrode with commercial activated carbon/CNT hybrid paper as anode and using the 6 M KOH solution as electrolyte, an asymmetric supercapacitor was assembled. The materials in hybrid paper electrodes can be used not only as electrode's active materials, but also as current collectors. The supercapacitor shows an energy density of 23.9 Wh kg −1 and a power density of 698.6 W kg −1 as well as good stability of 88.2% capacitance retention after 3000 cycles.