Papers by Keyword: Ternary Oxides

Abstract: A facile strategy of uniform flower-shaped binary-metal-based metal-organic frameworks (MOFs) has been successfully synthesized via a simple hydrothermal method as the precursor of porous Mn₂NiO₄ nanostructures. After heat treatment at different temperatures, the as-prepared Mn₂NiO₄ inherits the morphologies of MOFs and can hold until 450°C. This porous Mn₂NiO₄, used as supercapacitor electrodes, exhibits a high specific capacitance (531.5 F g^-1 at a current density of 1.0 A g^-1), with a relatively high specific surface area (114.2 m² g^-1). The high capacitance is mainly attributed to the porous and hierarchical structure, which facilitates fast diffusion of active ions, improves structural stability and large contact area between Mn₂NiO₄ and the electrolyte. The developed synthetic strategy may provide design guidelines for constructing advanced ternary nanostructured supercapacitors electrode.

Abstract: The well-aligned growth structures which derive from directional solidification of ceramic eutectics are of great interests due to their potential use in electronic devices and as structural materials at high temperatures. Because of the complexity of the component system and very high melting points, the solidification behavior on the oxide ceramic eutectic is still unclear up to date. In the presented paper, the Al₂O₃-Y₂O₃-ZrO₂ ternary eutectic ceramic is remelted by a DTA apparatus. The maximal heating temperature is 1950 °C. The melting and solidification behavior are investigated by the DTA analysis. The solidification microstructure is investigated by scanning electron microscopy (SEM), energy disperse spectroscopy (EDS) and X-ray diffraction (XRD). The results show that solidus temperature and the liquidus temperature are 1738.4 °C and 1750.1 °C, respectively. The formation path of eutectic phase is discussed. The microstructure of as-solidified eutectic ceramic shows a divorced ternary eutectic structure consisting of Al₂O₃, YAG and ZrO₂ phases with a random distribution. Furthermore, the microstructural comparison with directionally solidified ternary eutectic ceramic is presented and discussed.