通过调整载体度来提高三元纳米晶体的热电性能
Yixin Zhao1, Jeffrey S Dyck, Brett M Hernandez
1Center for Chemical Dynamics and Nanomaterials Research, Department of Chemistry, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, USA.
Journal of the American Chemical Society
|March 25, 2010
概括
化学合成的甲化物 (Bi(2) Te(3)) 纳米晶体 (NCs) 的载体度通过创建三元的Bi(2-x) Sb(x) Te(3) NCs来调整. 这种调整显著改善了功率因子,与母公司Bi(2)Te(3) 相比,功率因子提高了三倍.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 固态物理 固态物理
背景情况:
- 石化 (Bi(2) Te(3) 是一个众所周知的热电材料.
- 控制载体度对于优化热电性能至关重要.
- 纳米晶体合成为材料属性调节提供了独特的机会.
研究的目的:
- 调查反 (Sb) 替代对基于Bi(2) Te(3) 的纳米晶体 (NC) 载体度的影响.
- 为了确定三元Bi{2-x) Sb{x) Te{3) 的NC能否达到可调节的载体度.
- 为了评估载体度调整对热电功率因子的影响.
主要方法:
- 基于Bi(2) Te(3) 的纳米晶体的化学合成.
- 用反 (Sb) 部分替代 (Bi) 形成三元的Bi2-x) Sb-x) Te-3) NCs.
- 含有Sb的系统变化 (x = 0.02,0.05,0.10,0.20,0.50,和1.50). 这些变化是指Sb含量的系统变化.
- 测量和分析载体度和功率因子.
主要成果:
- 通过Sb替代,Bi(2) Te(3) NCs的载体度成功地被调整了超过一个数量级.
- 第三种Bi{2-x) Sb{x) Te{3) 的NC显示了可调节的载体度,通过Sb/Bi的立体比控制.
- 与原始的Bi{2}Te{3}NC相比,立体三元Bi{2}-x) Sb{x) Te{3}NC的功率因子得到了三倍的改进.
结论:
- 用Sb部分替换Bi是一种有效的策略,用于调整Bi(2) Te(3) NCs的载体度.
- 在三元的Bi{2-x) Sb{x) Te{3) NC中对载体度的受控调整导致热电功率因子的显著增强.
- 这项工作展示了在纳米级优化热电材料的新途径.
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