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The selection of electrode materials and the optimization of electrode configurations are two effective approaches to achieve high-performance energy storage. As a representative ternary metal oxide, CoMoO 4 has been directly grown on the carbon cloth via a facile hydrothermal method and subsequent calcination, forming a binder-free electrode. Further measurements reveal that this electrode is composed of CoMoO 4 nanosheets assembled 3D-framworks (NAFs) and thereby shows a superb electrochemical property in KOH solution. It is worth mentioning that the specific capacitance reaches as high as 1234 F/g at the current density of 1 A/g, which exceeds most of CoMoO 4 and CoMoO 4 -based composites reported so far. Meanwhile, when the current density increases to 10 A/g, a considerable specific capacitance of 446 F/g is still obtained and can maintain nearly unchanged after 5000 cycles. [ABSTRACT FROM AUTHOR]

Ternary metal oxides have great potential for chemical storage devices because of their outstanding synergistic effects as well as rich redox reactions. However, there are limited reports of 3D structure BiCoO 3 materials and relevant electrochemical properties. Meanwhile, the study of BiCoO 3 is reasonably important for underlying metal oxides researches. In this work, we have successfully developed a 3D urchin-like BiCoO 3 material without using any template and surfactant. For the supercapacitor application, the BiCoO 3 material showed a specific capacitance of 152 F g −1 at the current density of 1 A g −1 , and this value exhibited a rate capability of 82.3% at a high current density of 10 A g −1 . Furthermore, the sample showed the ideal cycling stability (92.7% retention after 5000 times cycles at the current density of 1 A g −1 and nearly invariable specific capacitance during different current density cycles). These results suggest that the obtained urchin-like BiCoO 3 sample has superb electrochemical performances which suggest its promising applications as renewable and clean energy storage devices electrode materials in the future. [ABSTRACT FROM AUTHOR]

Low-cost dynamic materials for Faradaic redox reactions are needed for high-energy storage supercapacitors. A simple and cost-effective hydrothermal process was employed to synthesize amaryllis-like NiCo 2 S 4 nanoflowers. The sample was characterized by X-ray powder diffraction, Brunauer–Emmett–Teller method, scanning electron microscopy, and transmission electron microscopy. NiCo 2 S 4 nanoflowers were coated onto carbon fiber fabric and used as a binder-free electrode to fabricate a solid-state supercapacitor compact device. The solid-state supercapacitor exhibited excellent electrochemical performance, including high specific capacitance of 360 F g −1 at scan rate of 5 mV s −1 and high energy density of 25 W h kg −1 at power density of 168 W kg −1 . In addition, the supercapacitor possessed high flexibility and good stability by retaining 90% capacitance after 5000 cycles. The high conductivity and Faradic-redox activity of NiCo 2 S 4 nanoflowers resulted in high specific energy and power. Thus, NiCo 2 S 4 nanoflowers are promising pseudocapacitive materials for low-cost and lightweight solid-state supercapacitors. [ABSTRACT FROM AUTHOR]

In the work, four types of typical morphologies of differently dimensional pure V 2 O 5 nanostructures including nanoflowers, nanoballs, nanowires and nanorods were synthesized through a simple hydrothermal method. The morphology of the product depends on the types of solvent and acid. Hierarchical nanoflowers and zero-dimensional (0D) nanoballs of V 2 O 5 nanocrystals were obtained when using C 2 H 5 OH as solvent. One dimensional (1D) nanowires and nanorods were obtained if H 2 O was used to participate in the reaction. The morphology and structure of the samples were characterized by XRD and SEM, respectively. The electrochemical behaviors of nanoflowers, nanoballs, nanowires and nanorods as electrodes in a supercapacitor device were tested using cyclic voltammetry (CV) curves and galvanostatic charge–discharge (GCD) curves. The electrochemical test results indicate that the rod-like structure leads to a significant improvement of storage capacity, electrochemical kinetics and rate capability. And 1D V 2 O 5 nanorods show the largest specific capacitance of 235 F g −1 at the current density of 1 A g −1 when used as supercapacitor electrode in 1 mol/L Na 2 SO 4 electrolyte. It turns out that 1D V 2 O 5 nanorod is an ideal material compared with other morphologies for supercapacitor electrode. [ABSTRACT FROM AUTHOR]