| ZnE (E=S, Se, Te) are II -VI compound semiconductor materials with wide and direct band gap. With the excellence propertiesof photoelectricity and photoelectric conversion, ZnE shows great potential application in photo devices, solar cell, piezoelectric and laser applications.In this paper, with the assistance of NiS, CuSe, PbSe, SnTe and Cu nanoparticles, ZnE and CuZn one-dimensional nanostructures have been successfully produced by a simple chemical vapor deposition (CVD) method on Si substrates. The following major achievements were realized.1. Zinc blende structure ZnS nanowires have been successfully synthesized at about 700℃ by using NiS nanocrytal as the catalyst. The average diameter of the nanowires was 200nm, and the length was about 25μm. With the effect of redox reaction, vapor-liquid-solid (VLS) growth mechanism was proposed to understand the growth process. ZnS nanowires preferentially grow along [1 1 1] direction. Meanwhile, we have successfully controlled the growth of ZnS nanowires of a smaller diameter by using the smaller NiS nanoparticles.2. CuSe nanoparticles and Zn powder were used as source materials. Ultra long ZnSe nanowires with the length of 0.35-0.7mm were prepared in high purity Ar gas. In the initial growth stage of ZnSe nanowires, surface layer CuSe nanoparticles were used as catalyst particles and Se source, In the growth process, low layer CuSe would be decomposed to Se2, which was absorbed by the catalyst particles. So, it supplied the chance of the ultralong ZnSe nanowires growth in the coming stage. According to the analysis on the synthesis of ultralong ZnSe nanowires, it is believed that Cu has a strong ability in the absorption of Zn gas at high temperature.We have also successfully obtained CnZn alloy nanorods with Cu nanoparticles and Zn powder as source materials. The club like nanorods are heavy sticks with the thicker top and the thinner bottom. The value of Cu content in the bottom of club...
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