No abstract

No abstract

In this study, b-phase nickel hydroxide with a hexagonal brucite structure has been meshed with successive ionic layer adsorption and reaction deposited cupric oxide. The nanocomposite was characterized by X-ray diffraction, scanning electron microscopy and UV-Vis-NIR spectroscopy. The electrochemical performances of the nanocomposite Ni(OH) 2 /CuO supercapacitor were tested by cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy tests in 1 M KOH solution. With the potential window between 0 and 0.5 V, a maximum specific capacitance *27 F/g was observed at a scan rate of 10 mV/s. Moreover, Ni(OH) 2 /CuO electrode in the symmetric device shows a low energy (1.0 Wh/kg) and power (242 W/kg) density.

In contributing to the improvement of Ferrite Magnetic nanoparticles, the effects of Poly (Vinyl Pyrrolidone) (PVP) and annealing on the structural and magnetic properties of Zinc ferrite nanoparticles (ZFNPs) synthesis were investigated in this work. The effects were evaluated using the X-ray diffraction (XRD) spectroscopy, Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and Vibrating sample magnetometer (VSM). The XRD analysis confirms a good formation of the inverse spinel crystal structure with an average particle size of 1.3 nm to 15.2 nm and from 1.6 nm to 21.1 nm for the ZFNPs as-prepared and PVP mediated ZFNPs for the un-annealed and annealed samples, respectively. The SEM image reveals an increase in the particle size for both the as-prepared and PVP mediated samples after annealing at 500˚C. The FTIR also reveals the inverse spinel structure for the as-prepared and annealed samples, which witnesses a vibrational red shift towards a higher wave number for the annealed samples. The VSM analysis indicates the superparamagnetic behavior of PVP mediated and annealed sample with zero remanence magnetization (Mr) and Coercivity (Hc). The saturation magnetization (Ms) increases from 1.31 emu/g, for the as-prepared samples, to 4.31 emu/g after the annealing and from 1.18 emu/g, for the PVP mediated, to 6.38 emu/g after annealing. These effects have been attributed to the cationic rearrangement on the lattice site after the annealing. This presents a superior material for various applications in nanotechnology.

No abstract