Low Temperature Synthesis and Electrical Characterization of Solid Chalcogenides using Molten Salts

熔融多硫族化物盐和水热技术将是 用于探索低温合成新型硫属化合物材料 和中间温度。 这两种合成技术都将使用 在与后过渡金属的反应中的各种A2 Ox盐， 主群元素 反应温度在200-500 oC之间 将被研究，因为这个范围已经很少探索 以前。 已经证明在这种温度下 一系列具有新结构类型的新材料可以形成， 结晶 硫、硒和 在两个和三个不同的子结构之间架起桥梁 尺寸，和相对较低的温度提供了一个有利可图的 这为合成大量新化合物提供了机会。 这些新化合物的物理性质有待探索，包括 磁性、作为温度函数的吸附和氧化还原 特性. 为了探测不寻常的电子现象， 新化合物的电荷传输特性将在 详细通过可变温度四探针电阻率以及 热电功率（Seebeck）测量。 测量结果将 主要是在单晶样品上进行。 这项赠款是由材料司共同支持的 研究和化学部。

Molten polychalcogenide salt and hydrothermal techniques will be used to explore the synthesis of new chalcogenide materials at low and intermediate temperatures. Both synthetic techniques will use various A2Qx salts in reactions with late transition metals and main-group elements. Reactions at temperatures between 200-500 oC will be studied because this range has been little explored previously. It has been demonstrated that in this temperature range new materials with new structure types can form and crystallize. The remarkable ability of sulfur, selenium, and tellerium to bridge different sub-structures in two and three dimensions, and the relatively low temperatures provide a lucrative opportunity for synthesis of a very large number of new compounds. Physical properties of these new compounds to be explored include magnetic, sorption as a function of temperature, and redox properties. In order to probe unusual electronic phenomena, the charge transport properties of the new compounds will be studied in detail via variable temperature four-probe resistivity as well as thermoelectric power (Seebeck) measurements. The measurements will be primarily done on single crystal samples. This grant is jointly supported by the Division of Materials Research and Chemistry Division.