Orientation of CuInS2 nanowires and estimation method of Optical gap

对于化学处理法制备的CuInS_2纳米线，发现合成温度是形成线状或带状纳米结构的关键参数。为了硬化CuInS_2纳米线，我们尝试对CuInS_2纳米线进行退火热处理。CuInS_2纳米线在700℃的热处理后仍然存在。为了评估CuInS_2纳米线的光学带隙，我们在短波长范围内观察到了CuInS_2纳米线的板状光致发光，并与块体CuInS_2晶体的发射进行了比较。利用相干椭圆偏振分析，通过偏振度的研究，建立了光学带隙的估算方法。然而，我们的结果适用于CuInS_2纳米线，由于纳米线粉末含有其他产物的混合物，因此我们的结果存在不清楚的部分，因此认为产物的偏振度是影响偏振度的因素。CuInS_2纳米线与其他产品的分离将是下一阶段的重要课题。伪介电函数RESTO…首次从CuInS_2纳米线的椭圆偏振光谱数据中获得了更多的红光。通过比较块状CuInS_2与带状和线状纳米线样品的伪介电函数，发现CuInS_2的电子光谱发生了一定的变化。人们可以注意到，带状纳米线填充的样品的伪介电函数的实部和虚部都与块状CuInS_2有足够的相似性。作为类似的化合物纳米结构，成功地制备了TlInSe_2纳米棒和纳米颗粒。对块状晶体为棒状基态的一维TlInSe_2的电子带态进行了LCAO(原子轨道线性组合)分析。从计算结果中，我们了解了该材料中光学跃迁的选择规律。实验结果与介电函数和光致发光光谱的偏振特性很好地吻合。用四种探针法在真空中测量了被称为p型导体的TlInSe_2的Seebeck系数，温度范围为70℃到500℃。随着温度降至200℃以下，该系数变得正且巨大，达到10^7μV/℃的尖端数值。根据TlInSe_2中可能在低于200℃的温度下发生的无公度超晶格相讨论了所获得的结果，并由此导致了该材料上述独特的热电性能。预计基于TlInSe_2的热电器件将具有优越的参数。较少

For synthesis of CuInS_2 nanowires using chemical treatment method, it is found that the synthesis temperature is key parameter to form nanostructure of thread type or belt type. In order to harden CuInS_2 nanowires, we tried to anneal treatment of CuInS_2 nanowires. CuInS_2 nanowires remain after anneal treatment at 700℃.For evaluation of optical bandgap of CuInS_2 nanowires, board photoluminescence emissions have been observed in the short wavelength range compared with the emission of bulk CuInS_2 crystals. We have established estimation of optical band gap by investigation of polarization degree using coherent ellipsometry analysis. However, our results applying to CuInS_2 nanowires includes unclear parts because the nanowire powders have mixture of other products and then it is considered that the polarization degree is affected by the products. The isolation of CuInS_2 nanowires from the other products would be important theme in the next stage.The pseudodielectric function resto … More red from the spectroellipsometric data of CuInS_2 nanowires has been investigated for the first time. The electronic spectrum, as a whole, undergoes certain changes displayed by comparison of the pseudodielectric function of bulky CuInS_2 with that of the samples with belt-type and thread-type nanowires. One can notice that in both real and imaginary parts of pseudodielectric function of the samples populated with belt-type nanowires are enough of resemblance with bulky CuInS_2.As analogous compound nanostructure, preparation of TlInSe_2 nanorodes and nanoparticles has been succeeded. LCAO (linear combination of atomic orbitals) analysis of the electronic band states has been completed for one-dimensional TlInSe_2 having rod-like ground state shape of bulky crystal. From the results, we obtained knowledge of the selection rule of optical transition in this material. The results agree well with polarization properties of dielectric functions and photoluminescence spectra.Seebeck coefficient of TlInSe_2, known as a p-type conductor, has been measured in the temperature range 70℃ to 500℃ in vacuum by using four probe techniques. With temperature down to below 200℃, the coefficient is becoming positive and huge to a cutting-edge value of 10^7μV/℃. The obtained results are discussed in terms of an incommensurate superlattice phase, which might have taken place in TlInSe_2 at temperatures below 200℃, and led to the above unique thermoelectric properties of this material. It is expected that thermoelectric devices based on TlInSe_2 will have superior parameters. Less