具有同质多面体层的异基材料的低导热性
Chi Zhang1, Jiangang He1, Rebecca McClain2
1Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|February 3, 2022
概括
研究人员开发了一个减法策略来合成纯相BiAgOSe,这是一个有前途的热电材料. 这种新方法产生了比BiCuOSe更低的导热率的半导体,表明了提高热电性能的潜力.
科学领域:
- 材料科学
- 固态化学
- 热电材料
背景情况:
- 银氧化物 (BiAgOSe) 是热电材料BiCuOSe的类似物.
- 由于稳定中间体的形成驱动力较低,BIAgOSe的合成具有挑战性.
研究的目的:
- 为合成纯相BiAgOSe开发一个"减法策略".
- 研究BiAgOSe的电子结构和热传输特性.
主要方法:
- 用减法策略进行水热合成.
- 电子结构计算 (例如DFT).
- 视觉特征.
- 电网导热度测量
- 格子动态模拟
- 可变温度衍射测量
主要成果:
- 纯相BiAgOSe已经成功合成.
- BiAgOSe是一种间接带隙半导体,带隙为0.95 eV.
- 与BiCuOSe相比,BiAgOSe的晶格导热率明显较低.
- 低导热性归因于柔软的Ag-Se键和亚晶格不匹配.
结论:
- 减去策略对于合成纯相BiAgOSe是有效的.
- 由于其低导热性,BiAgOSe显示出作为热电材料的潜力.
- 通过化学操纵多面体来控制声子传输是优化热电性能的可行策略.
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