ABSTRACT: A series of Ni–Co oxide nano-composites were prepared by thermal decomposition of the precursors obtained via coordination
homogeneous co-precipitation method. Thermogravimetric analysis (TGA), powder X-ray diffraction (XRD), and transition electron
microscopy (TEM) tests were applied to investigate the thermal behavior, crystalline. and morphology of the Ni–Co oxide composites.
The electrochemical properties of Ni–Co oxide electrodes were evaluated by cyclic voltammetry, galvanostatic charge–discharge,
and electrochemical impedance measurements. Results showed that the calcination temperature had great effect on morphology
and specific capacitance of product. The effect of the molar ratios of Ni2+/Co2+ in the reaction system on the electrochemical properties of Ni–Co oxide electrodes was also discussed.
Journal of Materials Science 05/2012; 44(11):2828-2835. · 2.02 Impact Factor
ABSTRACT: Ni–Co oxide nanocomposite was prepared by thermal decomposition of the precursor obtained via a new method—coordination homogeneous
coprecipitation method. The synthesized sample was characterized physically by X-ray diffraction, scanning electron microcopy,
energy dispersive spectrum, transmission electron microscope, and Brunauer–Emmett–Teller surface area measurement, respectively.
Electrochemical characterization of Ni–Co oxide electrode was examined by cyclic voltammetry, galvanostatic charge–discharge,
and electrochemical impedance measurements in 6-mol L−1 KOH aqueous solution electrolyte. The results indicated that the addition of cobalt oxide not only changed the morphology
of NiO but also enhance its electrochemical capacitance value. A specific capacitance value of 306F g−1 of Ni–Co oxide nanocomposite with n
Co = 0.5 (n
Co is the mole fraction of Co with respect to the sum of Co and Ni) was measured at the current density of 0.2A g−1, nearly 1.5 times greater than that of pure NiO electrode. Lower resistance and better rate capability can also be observed.
Journal of Solid State Electrochemistry 04/2012; 13(9):1387-1394. · 2.13 Impact Factor
ABSTRACT: CuO/ZnO nano-composites were successfully prepared via coordination oxidation homogeneous co-precipitation method. Thermogravimetric and differential thermal analysis (TG–DTA), FT-IR, field-emission scanning electron microscope (FESEM), energy dispersive X-ray spectrometry (EDS), transmission electron microscope (TEM), powder X-ray diffraction (XRD) were used to characterize the microstructure and morphology of the precursor and the products obtained at various temperatures. The research on the growth dynamics of product showed that the dynamic growth index was 5, the growth speed constant K was 4.93 × 104 nm5/min and the apparent activation energy presented differently in the low-temperature region and high-temperature region with the values of 14.94 kJ/mol and 59.84 kJ/mol, respectively. The results of the photocatalytic degradation of methyl orange (MO) in aqueous solution indicated that, with the calcining temperature increasing, the photocatalytic performance of the product increased first, and then began to decrease when the calcining temperature got to 450 °C because the particle size increased.
Materials Science and Engineering: B. 150(2):99-104.