We have synthesized the hybrid supercapacitor electrode of Co3O4 nanoparticles on vertically aligned graphene nanosheets (VAGNs) supported by carbon fabric. The VAGN served as an excellent backbone together with the carbon fabric, enhancing composites to a high specific capacitance of 3480 F/g, approaching the theoretical value (3560 F/g). A highly flexible all-solid-state symmetric supercapacitor device was fabricated by two pieces of our Co3O4/VAGN/carbon fabric hybrid electrode. The device is suitable for different bending angles and delivers a high capacitance (580 F/g), good cycling ability (86.2% capacitance retention after 20 000 cycles), high energy density (80 Wh/kg), and high power density (20 kW/kg at 27 Wh/kg). These excellent electrochemical performances, as a result of the particular structure of VAGN and the flexibility of the carbon fabric, suggest that these composites have an enormous potential in energy application.

New layered SnS2 nanosheet arrays consisting of 1–5 atomic layers were synthesized directly on Sn foil as both the tin source and the metal current collector substrates by a simple biomolecule-assisted method. It is found that SnS2 nanosheets synthesized have excellent photoelectric applications, such as on lithium ion batteries, and photocatalytic, field emission, and photoconductive properties. Cyclic voltammetry and discharge and charge behaviors of the atomic SnS2 nanosheets were examined, and it shows that the average discharge capacity in 1050 mAh/g is much larger than the theoretical capacity at the 1C rate. The photocatalytic action driven by solar light is quite quick, and the degradation rate of RhB is 90%, only irradiated for 20 min when the content of SnS2 nanosheets is 0.4 g/L. The response of the SnS2 device to the incidence UV light is very fast and shows excellent photosensitivity and stability. In addition, field emission properties of SnS2 nanosheets were also researched, and we found that the turn-on field for SnS2 is 6.9 V/μm, which lowered ever reported values. The enhanced photoelectric properties are likely to originate in a graphene-like structure. Thus, graphene-like SnS2 materials are promising candidates in the photoelectric field.

Highly efficient energy storage systems are in great demand for power source applications ranging from wearable electronics to hybrid electric vehicles. Graphene-based hybrid structure capacitors are ideal candidates for manufacturing these systems. Herein, we present the design and fabrication of heterostructured composites made of vertically aligned graphene nanosheets (VAGN) and MnO nanoparticles. Electrodes with various MnO mass contents were obtained by depositing nanosized MnO particles onto VAGN under different hydrothermal conditions. The VAGN served as an excellent backbone and electron collector, enhancing the specific capacitance of the VAGN/MnO electrode (37 wt% MnO) to 790 F g À1 at a scan rate of 2 mV s À1 . The electrodes also showed high specific capacitance (381 F g À1 ) with high active material loading content (80 wt% MnO), and outstanding cycling stability (80% retention after 4000 cycles at 10 A g À1 ). These excellent electrochemical performances result from the particular three-dimensional structure of VAGN, which offers convenient access for electrolyte cations participating in the redox reaction of MnO. These composites show enormous potential for use in energy management applications.

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A 3D-composite structure of FeP nanorods on vertically aligned graphene nanosheets has been fabricated for the high-performance hydrogen evolution reaction.

ZnO has been regarded as a promising anode material for the next-generation lithium-ion battery. Unfortunately, the structure broken caused by the volume change of ZnO and the capacity degression due to the irreversible electrochemical reaction of ZnO still remain two major challenges. Here, we design a novel kind of in situ growth binder-free ZnO-based anodes via ZnO anchored on vertically aligned graphene. The composite anode retains physical integrity post cycling. Especially, the good conductivity of graphene and the ultrasmall size of ZnO particles help to produce a completely reversible electrochemical reaction of ZnO-based anode. The composite material exhibits a high capacity (810 mAh g(-1)), long cycle life, good cycle stability, and fast charge/discharge rate.

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We have made a supercapacitor electrode based on carbon fabric, vertically aligned graphene nanosheets (VAGN) and Mn3O4 nanoparticles.