No abstract

No abstract

No abstract

No abstract

The specific capacity and cycling performance of the hierarchical electrode were significantly enhanced due to the sulfur doping into Co3O4.

No abstract

In this work, we synthesized the hierarchical ZnO@C@NiO core-shell nanorods arrays (CSNAs) grown on a carbon cloth (CC) conductive substrate by a three-step method involving hydrothermal and chemical bath methods. The morphology and chemical structure of the hybrid nanoarrays were characterized in detail. The combination and formation mechanism was proposed. The conducting carbon layer between ZnO and NiO layers can efficiently enhance the electric conductivity of the integrated electrodes, and also protect the corrosion of ZnO in an alkaline solution. Compared with ZnO@NiO nanorods arrays (NAs), the NiO in CC/ZnO@C@NiO electrodes, which possess a unique multilevel core-shell nanostructure exhibits a higher specific capacity (677 C/g at 1.43 A/g) and an enhanced cycling stability (capacity remain 71% after 5000 cycles), on account of the protection of carbon layer derived from glucose. Additionally, a flexible all-solid-state supercapacitor is readily constructed by coating the PVA/KOH gel electrolyte between the ZnO@C@NiO CSNAs and commercial graphene. The energy density of this all-solid-state device decreases from 35.7 to 16.0 Wh/kg as the power density increases from 380.9 to 2704.2 W/kg with an excellent cycling stability (87.5% of the initial capacitance after 10000 cycles). Thereby, the CC/ ZnO@C@NiO CSNAs of three-dimensional hierarchical structure is promising electrode materials for flexible all-solid-state supercapacitors.

Reduced-graphene oxide/molybdenum oxide/polyaniline ternary composites, RGO(MP), for use as electrode materials for high energy density supercapacitors, were firstly synthesized using a one-step method with Mo 3 O 10 (C 6 H 8 N) 2 $2H 2 O and graphene oxide (GO) as precursors. When the mass ratio of Mo 3 O 10 (C 6 H 8 N) 2 $2H 2 O to GO is 8 : 1, the resulting composite RGO(MP) 8 shows excellent electrochemical performance with a maximum specific capacitance of 553 F g À1 in 1M H 2 SO 4 and 363 F g À1 in 1 M Na 2 SO 4 at a scan rate of 1 mV s À1 . Its energy density reaches 76.8 W h kg À1 at a power density of 276.3 W kg À1 , and 28.6 W h kg À1 at a high power density of 10294.3 W kg À1 in H 2 SO 4 . While in Na 2 SO 4 , the energy density achieves 72.6 W h Kg À1 at a power density of 217.7 W kg À1 and 13.3 W h Kg À1 at power density of 3993.8 W kg À1 , respectively. The composite also presents good cycling stability (86.6, 73.4% at 20 mV s À1 after 200 cycles in 1 M H 2 SO 4 and Na 2 SO 4 , respectively).