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Alloyed ternary CdSxSe1-x nanorods have been synthesized by the thermal treatment of Cd2+-dispersed polyethylene glycol 2 000 gel (PEG 2000) with ethylenediamine solution of sulfur and selenium in a sealed system at 180 °C for 24 h, in which the ratio of S to Se in the nanorods was controlled by adjusting the relative amounts of the starting materials. Based on the results of experiments, it is found that the CdSxSe1-x nanorods were also synthesized with several sulfur sources by the method. X-ray diffraction (XRD) shows that the alloyed ternary CdSxSe1-x nanorods are highly crystalline, and no other phase was observed in these nanorods.

Three kinds of tetrapod-like ZnO nanostructures have been synthesized simultaneously via pure Zn chemical vapor deposition on silicon wafers with (111) orientation (Si (111)) at 920 °C. X-ray diffraction indicates that the nanotetrapods are of wurtzite structure. The morphology and the microstructure of the nanotetrapods are investigated by the scanning electron microscopy. Selected area electron diffraction shows the growth direction, and energy dispersive X-ray spectroscopy reveals the atomic composition ratio of Zn/O. The growth process is briefly discussed. The optical property of the products was also recorded by means of photoluminescence spectroscopy.

Leaching studies of low-grade pyrolusite, containing 11.84% Mn with high silicon, were carried out using sodium sulfite as a reductant in ammonium sulfate medium. Various process parameters including temperature, leaching time, solid-liquid ratio, quantity of ammonium sulfate, as well as the amount of reducing agent were studied in detail. The manganese extraction yield was the response of the process. Temperature and reagent concentration exerted the most important positive effect on the manganese extraction. The optimized conditions showed that when the amount of reducing agent was a stoichonmetric amount, over 90% manganese extraction and the lowest impurities were achieved, the amount of heavy metal impurities in the manganese leaching liquid was less than 5 mg/L, and almost no iron and aluminum were extracted in 3 mom ammonium sulfate concentration at 100 °c in 45 min.

The sizes and morphologies of hexagonal phase ZnO crystals were successfully controlled by a hydrothermal process in the presence of poly (acrylic acid) (PAA). The dosage of NaOH in this reaction system proved to be crucial in the growth process. With the increase of dosage from 0.7 g to 3.0 g, the morphologies of the ZnO crystals changed from nanoplates to microrods. Their optical properties were also investigated.

The nanometer MnO2 has outstanding electrochemical performance theoretically, but it is not suitable for actual utilization, which may result in capacity decrease and resource waste. In this study we have utilized the characterizations of the nanometer material, synthesized a type of nanometer α-MnO2 through KMnO4 and KNO3 with hydrothermal method, and mixed the products into micron electrolytic manganese dioxide (EMD) to enhance the electrochemical performance of the electrode. The cyclic voltammogram and galvanostatical discharge measurements of the samples were investigated. It is found that the 50% nanometer MnO2 mixed electrode has the best electrochemical performance. The electrochemical performance improvement mechanism of the sample nanometer MnO2 mixed into micron EMD was discussed. With the existence of electrolyte, the nanometer MnO2 particles filled into the interspaces of the micron EMD particles, the mass and charge transfer conditions of the electrode reaction were improved, and the electrode polarization was diminished.