Bi2Te3 基花状纳米片粉体的制备及热电性能研究

本文通过选用不同乙二胺四乙酸(EDTA) 的用量采用水热法制备出了具有花状纳米片形貌的碲化铋(Bi2Te3 ) 纳米粉体, 研究了不同 EDTA 的用量对 Bi2Te3 纳米粉体花状纳米片形貌的影响, 结果表明 EDTA 的用量对粉体的成相和形貌有很大的影响. EDTA 用量为0.2 g 是最佳值, 有助于形成纯相的 Bi2Te3 花状纳米片. 并以 Y元素掺杂为例, 研究了 EDTA 用量对元素掺杂 Bi2Te3 纳米粉体花状形貌的影响, 研究发现元素掺杂后对 Bi2Te3粉体的微观形貌有一定的影响. 为了保持元素掺杂 Bi2Te3 纳米粉体的花状形貌,EDTA 合适的用量至关重要. 以Y0 .2Bi1 .8Te3 为例, 研究了 EDTA 用量对样品的热电性能的影响. 结果表明, 花状纳米片形貌有利于在降低样品电阻率的同时有效降低样品的热导率, 从而大大增加了样品的ZT 值.

Preparation and Thermoelectric Propertiesof Bi2Te3 Based Flower-like Nanoplates

We prepared Bi2Te3 nanopowders with flower-like nanoplates morphology bythe hydrothermal method through using different amounts of the EDTA. The effects of the amounts of the EDTA on the flower-like nanoplates morphology of the Bi2Te3 nanopowders were investigated. The result showed that the amounts of the EDTA have significant effects on the phase structures and the morphology of the nanopowders. The optimum amount ofthe EDTA is 0. 2g which can be helpful to form Bi2Te3 nanopowders with pure phase and flower-like nanoplates morphology. And taking Y element doping for instance, we studied the effect of the surfactant EDTA on theflower-like morphology of Bi2Te3 nanopowders. The results showed that elements doping has some effects on the morphology of the nanopowders. In order to form the flower-like nanoplates morphology of the elements doping Bi2Te3 nanopowders, the appropriate amounts of the surfactant EDTA is a key factor. Taking Y0 .2Bi1 .8Te3 for example, the thermoelectric properties of the sample were investigated. The results showed that the flower-like nanoplates morphologyis helpful to decrease the electrical resistivity and the thermal conductivity, and hence to increase the ZT value.