초음파 분무 열분해법에 의한 산화물 환원 공정의 구형 Bi₂Te₃ 분말 합성

Bismuth telluride (Bi₂Te₃) and its alloys are well-known thermoelectric materials for ambient temperature applications. In this study, the dissolved Bi-Te precursor solution was used to synthesis metallic Bi₂Te₃ powder via ultrasonic spray pyrolysis and reduction process. The droplets of the Bi-Te precursor solution were decomposed to Bi-Te oxide powders by ultrasonic spray pyrolysis. The spherical Bi₂Te₃ powders were synthesized by reduction reaction in atmosphere of hydrogen gas at the temperature above 375℃ for 6h. The reduced Bi₂Te₃ powders have a mean particle size of 1.5 μm. The crystal structure of the powder was evaluated by X-Ray diffraction(XRD), and the microstructure with size and shape powders was observed by fieldemission scanning electron microscope(FE-SEM) and transmission electron microscope(TEM).