Enhanced thermoelectric performance of n-type PbTe bulk materials fabricated by semisolid powder processing
Enhanced thermoelectric performance of n-type PbTe bulk materials fabricated by semisolid powder processing
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DOI：
10.1016/j.jallcom.2014.04.116
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发表时间：
2014-10
影响因子：
6.2
通讯作者：
Deqing Mei;Yang Li;Zhehe Yao;Hui Wang;T. Zhu;Shaochen Chen
中科院分区：
文献类型：
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作者：
Deqing Mei;Yang Li;Zhehe Yao;Hui Wang;T. Zhu;Shaochen Chen
引入介观结构（0.1-1.0 μm）是降低热电材料热导率的有效途径之一。在这项研究中，n型PbTe体样品制备半固态粉末加工（SPP）使用熔融合成的粉末。场发射扫描电子显微镜（FESEM）结果表明，SPP法制备的样品晶粒内存在圆形的介孔。介观孔通过增强具有长平均自由程的声子的散射，有效地降低了晶格热导率。在773 K时，SPP制备的样品的品质因数（ZT）值为1.33，与热压样品相比，ZT值提高了77%。这种增强主要是由于SPP样品较低的晶格热导率和较高的功率因数。
The introduction of mesoscale (∼0.1–1.0 μm) structures is one of effective approaches to reduce the thermal conductivity of thermoelectric materials. In this study,n-type PbTe bulk samples were fabricated by semisolid powder processing (SPP) using powders synthesized by melting. The field emission scanning electron microscope (FESEM) results showed that there were circular mesoscale pores in the grains of the samples fabricated by SPP. The mesoscale pores effectively reduced the lattice thermal conductivity by enhancing the scattering of phonons with long mean free paths. The samples fabricated by SPP had a figure of merit (ZT) value of 1.33 at 773 K, which showed an enhancement of 77% compared with that of their hot-pressed counterparts. This enhancement mainly resulted from the lower lattice thermal conductivity and higher power factor of the SPP samples.