▎ 摘　　要

delta-MnO2/holey reduced graphene oxide (HRGO) fiber electrodes with good flexibility and enhanced electrochemical performance were prepared by depositing delta-MnO2 on the surface of the holey reduced graphene oxide fibers. HRGO-650 was obtained by soaking graphene oxide in a 0.5 M H3PO4 solution for 12 h followed by calcining it at 650 degrees C for 2 h in N-2. The loose curling manganese oxide nanosheets are reassembled on the surface of the HRGO-650 fiber freely, causing the close contact between the manganese oxide nanosheets and the graphene nanosheets. The prepared delta-MnO2(4.0)/HRGO fiber electrode shows a larger specific capacitance (245 F g(-1)) at a current density of 1 A g(-1) in the 1 M Na2SO4 electrolyte. An all-solid-state fiber supercapacitor was assembled by two intertwined delta-MnO2(4.0)/HRGO fiber electrodes, both of which are solidified in a H3PO4-polyvinyl alcohol (PVA) gel electrolyte. This all-solid-state delta-MnO2(4.0)/HRGO fiber supercapacitor not only shows good flexibility, but also gives enhanced capacitive performance. The optimal all-solid-state delta-MnO2(4.0)/HRGO fiber supercapacitor obtains a high area-specific capacitance (16.3-16.7 mF cm(-2)) at a current density of 0.05 mA cm(-2), enhanced rate capability (64% capacitance retention from 0.05-0.6 mA cm(-2)), and relative good stability (80% of initial capacitance values after 1000 cycles). This method is expected to improve the conductivity and capacitance for all-solid-state carbon-based fiber supercapacitor with good flexibility and light weight.