Park Bo-In, Shin Miri, Park Jaeho, Lee Jae-Seung, Lee Seung Yong, Yu Seunggun
Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.
Materials Architecturing Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea.
Materials (Basel). 2021 Jan 22;14(3):536. doi: 10.3390/ma14030536.
In this study, BiSbTe (BST) nanoparticles (NPs) with high crystallinities were synthesized via a mechanochemical process (MCP). X-ray diffraction (XRD), and Raman and X-ray photoelectron spectroscopy (XPS) spectra of the BST NPs showed that the Bi, Sb, and Te powders successfully formed BiSbTe phase and transmission electron microscopy (TEM) images, verifying the high crystallinity and smaller size, albeit agglomerated. The as-synthesized BST NPs with agglomerated clusters were ground into smaller sizes of approximately 41.8 nm with uniform distribution through a simple wet-milling process during 7 days. The thermal conduction behaviors of bulk alloys fabricated by spark plasma sintering (SPS) of the BST NPs were studied by comparing those of samples fabricated from as-synthesized BST NPs and a BST ingot. The thermal conductivities () of the BST nanocomposites were significantly reduced by introducing BST NPs with smaller grain sizes and finer distributions in the temperature range from 300 to 500 K. The BST nanocomposites fabricated from wet-milled BST NPs offered ultralow values of 0.84 W m K at approximately 398 K.
在本研究中，通过机械化学过程（MCP）合成了具有高结晶度的BiSbTe（BST）纳米颗粒（NPs）。BST NPs的X射线衍射（XRD）、拉曼光谱和X射线光电子能谱（XPS）表明，Bi、Sb和Te粉末成功形成了BiSbTe相，透射电子显微镜（TEM）图像验证了其高结晶度和较小尺寸，尽管存在团聚。通过简单的湿磨工艺在7天内将合成的具有团聚簇的BST NPs研磨成尺寸约为41.8 nm且分布均匀的更小尺寸。通过比较由合成的BST NPs和BST铸锭制备的样品，研究了通过火花等离子烧结（SPS）由BST NPs制备的块状合金的热传导行为。在300至500 K的温度范围内，通过引入具有更小晶粒尺寸和更精细分布的BST NPs，BST纳米复合材料的热导率（）显著降低。由湿磨BST NPs制备的BST纳米复合材料在约398 K时提供了0.84 W m K的超低值。
