Enhancement of thermoelectric efficiency in PbTe by distortion of the electronic density of states
Enhancement of thermoelectric efficiency in PbTe by distortion of the electronic density of states
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DOI：
10.1126/science.1159725
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发表时间：
2008-07-25
期刊：
影响因子：
56.9
通讯作者：
Snyder, G. Jeffrey
中科院分区：
文献类型：
--
作者：
Heremans, Joseph P.;Jovovic, Vladimir;Snyder, G. Jeffrey
热电能量转换器的效率受到材料热电优值（zT）的限制。基于限制声子热传导的纳米结构的zT的最新进展接近基本极限：热导率不能降低到非晶极限以下。我们探讨了提高塞贝克系数，通过扭曲的电子态密度和报告的成功实施，通过使用碲化铅（PbTe）中的铊杂质水平。这样的能带结构工程导致p型PbTe中的zT在773开尔文下加倍至1.5以上。将这种新的物理原理与纳米结构结合使用以降低热导率可以进一步提高zT，并使热电系统能够更广泛地使用。
The efficiency of thermoelectric energy converters is limited by the material thermoelectric figure of merit (zT). The recent advances in zT based on nanostructures limiting the phonon heat conduction is nearing a fundamental limit: The thermal conductivity cannot be reduced below the amorphous limit. We explored enhancing the Seebeck coefficient through a distortion of the electronic density of states and report a successful implementation through the use of the thallium impurity levels in lead telluride ( PbTe). Such band structure engineering results in a doubling of zT in p- type PbTe to above 1.5 at 773 kelvin. Use of this new physical principle in conjunction with nanostructuring to lower the thermal conductivity could further enhance zT and enable more widespread use of thermoelectric systems.