As supercapacitor electrode materials, their structures, including specific surface area, instability, and interconnection, determine the electrochemical performances (specific capacitance, cycle stability, and rate performance). In this study, 1T-MoS2 nanosheets were self-assembled into nanoflowers via a one-pot facile hydrothermal reaction. The nanoflowers retain the excellent electrical conductive performance and the feature of inherent high specific surface area of the nanosheets. For the sheets are interconnected to each other in flower structure, the structure is more stable and the charges are more easily transferred. Thus, compared to the nanosheet electrode, the nanoflower electrode shows the remarkable advantage when used as the electrode of the energy-storage device, whether it is 1T phase or 2H phase in KCl or in KOH. When measured at 0.5 A g–1 in KOH electrolyte, the MoS2 nanoflower electrode exhibits a high specific capacitance of 1120 F g–1. At the same time, when cycling 2000 times at a current density of 10 A g–1, the capacitance retention ratio can reach up to 96%.

Silver-coated glass fibers have been successfully fabricated using a simple electroless silver plating. The structures of the silver/glass fiber composites were characterized by X-ray diffraction, high-resolution transmission electron microscopy, and scanning electron microscopy, respectively. The morphology investigation showed that the silver coatings were compact and continuous. The minimum volume resistivity could reach 4.53 9 10 -4 X cm, suggesting excellent electric conductivity. It was found that the quality of silver deposition was influenced by dosage of ammonia solution and plating temperature. Ammonia solution served as complexing reagent and supplied an alkaline media, and higher temperature easily led to metallic oxidation. The current method is simple-handle, inexpensive, large production, and the obtained silver/glass fibers can be used as fillers to fabricate electromagnetic wave shielding materials.

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It is well-known that in neutral and acidic aqueous electrolytes, MoS 2 monolayers can store charges by adsorption of cations on to the electrode-electrolyte interface as its analog of graphene. Restricted by its low conductivity and the charge storage mechanism, the electrochemical performance of MoS 2 monolayer supercapacitor electrode is not satisfactory. It is reported here that water bilayers absorbed on MoS 2 monolayers can be involved in charge storage. One proton of each absorbed water molecule can intercalate/de-intercalate the water bilayers during charging/discharging in the alkaline aqueous electrolyte. For two water molecules are present for every Mo atom, the water bilayers can endow MoS 2 monolayers an ultrahigh specific capacitance. In this paper, 1T phase MoS 2 nanosheets with three monolayers were synthesized by hydrothermal reaction. It presents a specific capacitance of 1120 F g −1 at a current density of 0.5 A g −1 in KOH. As it is assembled with active carbon into a hybrid supercapacitor, the device has an energy density of 31.64 Wh kg −1 at a power density of 425 W kg −1 , and gets a specific capacitance retention of 95.4% after 10,000 cycles at 2 A g −1 .

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