Coralloid and hierarchical Co3O4 nanostructures used as supercapacitors with good cycling stability

Toward Flexible and Wearable Embroidered Supercapacitors from Cobalt Phosphides-Decorated Conductive Fibers

Wearable supercapacitors (SCs) are gaining prominence as portable energy storage devices. To develop high-performance wearable SCs, the significant relationship among material, structure, and performance inspired us with a delicate design of the highly wearable embroidered supercapacitors made from the conductive fibers composited. By rendering the conductive interdigitally patterned embroidery as both the current collector and skeleton for the SCs, the novel pseudocapacitive material cobalt phosphides were then successfully electrodeposited, forming the first flexible and wearable in-plane embroidery SCs. The electrochemical measurements manifested that the highest specific capacitance was nearly 156.6 mF cm^-2 (65.72 F g^-1) at the current density of 0.6 mA cm^-2 (0.25 A g^-1), with a high energy density of 0.013 mWh cm^-2 (5.55 Wh kg^-1) at a power density of 0.24 mW cm^-2 (100 W kg^-1). As a demonstration, a monogrammed pattern was ingeniously designed and embroidered on the laboratory gown as the wearable in-plane SCs, which showed both decent electrochemical performance and excellent flexibility.

Highly Stable Gully-Network Co3O4 Nanowire Arrays as Battery-Type Electrode for Outstanding Supercapacitor Performance

3D transition metal oxides, especially constructed from the interconnected nanowires directly grown on conductive current collectors, are considered to be the most promising electrode material candidates for advanced supercapacitors because 3D network could simultaneously enhance the mechanical and electrochemical performance. The work about design, fabrication, and characterization of 3D gully-network Co3O4 nanowire arrays directly grown on Ni foam using a facile hydrothermal procedure followed by calcination treatment will be introduced. When evaluated as a binder-free battery-type electrode for supercapacitor, a high specific capacity of 582.8 C g-1 at a current density of 1 A g-1, a desirable rate capability with capacity retention about 84.8% at 20 A g-1, and an outstanding cycle performance of 93.1% capacity retention after 25,000 cycles can be achieved. More remarkably, an energy density of 33.8 W h kg-1 at a power density of 224 W kg-1 and wonderful cycling stability with 74% capacity retention after 10,000 cycles can be delivered based on the hybrid-supercapacitor with the as-prepared Co3O4 nanowire arrays as a positive electrode and active carbon as negative electrode. All the unexceptionable supercapacitive behaviors illustrates that our unique 3D gully-network structure Co3O4 nanowire arrays hold a great promise for constructing high-performance energy storage devices.

Co3O4 nanoparticles/MWCNTs composites: a potential scaffold for hydrazine and glucose electrochemical detection

We report the successful formation of cobalt oxide (Co₃O₄) nanoparticles/multi-walled carbon nanotubes (Co₃O₄/MWCNTs) composites as efficient electrocatalytic materials for chemical sensing.

Size–strain distribution analysis of SnO2 nanoparticles and their multifunctional applications as fiber optic gas sensors, supercapacitors and optical limiters

SnO₂ nanoparticles (NPs) were prepared by a wet chemical method and characterized by X-ray diffraction (XRD) (rutile tetragonal), Fourier transform infrared spectroscopy (FTIR) (Sn–O, 657 cm⁻¹) and micro Raman spectroscopy (Sn–O, 635 cm⁻¹).

Study on the oxidation process of cobalt hydroxide to cobalt oxides at low temperatures

The transformation process of cobalt hydroxide (Co(OH)₂) to cobalt oxides (Co₃O₄/CoOOH) in aqueous solution was studied in the temperature range of 50–90 °C.