Enhanced thermoelectric performance of n-type Nb-doped PbTe by compensating resonant level and inducing atomic disorder
Enhanced thermoelectric performance of n-type Nb-doped PbTe by compensating resonant level and inducing atomic disorder
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通过补偿谐振能级和诱导原子无序增强n型Nb掺杂PbTe的热电性能
DOI：
10.1016/j.mtphys.2022.100677
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发表时间：
2022-04
影响因子：
11.5
通讯作者：
Ang Ran
中科院分区：
文献类型：
--
作者：
Liu Hangtian;Sun Qiang;Zhong Yan;Xia Chengliang;Chen Yue;Shi Xiaolei;Chen Zhigang;Ang Ran
n型PbTe较差的热电性能限制了PbTe基热电器件的整体转换效率。在此，我们将Sb和Cu 2 Te引入到n型Nb掺杂PbTe中以实现超高热电性能。Sb和Cu的共掺杂有效地优化了载流子浓度以补偿Nb掺杂的PbTe合金中的谐振能级，并且因此在宽的温度范围内实现了上级电性能。同时，通过结合扩展的X射线吸收精细结构和详尽的电子显微镜研究，我们发现Nb和Sb在Pb位的替代诱导原子无序，如局部质量波动和局部应变变化，在晶格中，和Cu 2 Te进一步导致微米级偏析和纳米沉淀，这显着抑制晶格热导率。最终，在823 K时，Pb_（0.975）Nb_（0.02）Sb_（0.005）Te-0.004 Cu_（22）Te合金的峰值Z_T为1.32，在323 - 823 K范围内，Z_T平均值为1.01。基于我们的研究结果，我们创新性地采用全面的表征，揭示了在很宽的温度范围内的n型Nb掺杂PbTe的热电性能的起源，这应该推广到其他热电材料。
The inferior thermoelectric performance of n-type PbTe limits the overall conversion efficiency in PbTe-based thermoelectric devices. Here, we introduce Sb and Cu2Te into n-type Nb-doped PbTe for achieving ultra-high thermoelectric performance. The co-doping of Sb and Cu effectively optimizes carrier concentration to compensate for the resonant level in Nb-doped PbTe alloys, and consequently achieves superior electrical performance over a wide temperature range. Meanwhile, by combining extended X-ray absorption fine structure and exhaustive electron microscopy investigations, we found Nb and Sb substitutions at Pb sites induce atomic disorders, such local mass fluctuation and local strain variation, in the lattice, and Cu2Te further results in microsized segregations and nanoprecipitates, which significantly suppress lattice thermal conductivity. Eventually, a peakZTof ∼1.32 at 823 K and a high averageZTave∼1.01 in the range from 323 to 823 K are achieved in the Pb0·975Nb0·02Sb0·005Te-0.004Cu2Te. Based on our findings, we innovatively employ comprehensive characterization to reveal the origin of ultrahigh thermoelectric performance in n-type Nb-doped PbTe within a wide temperature range, which should be generalized to other thermoelectric materials.
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Cu 在协同优化 n 型 PbTe-Cu2Te 中声子和载流子传输方面的显着作用
影响因子：
15
作者：
Xiao Yu;Wu Haijun;Li Wei;Yin Meijie;Pei Yanling;Zhang Yang;Fu Liangwei;Chen Yuexing;Pennycook Stephen J.;Huang Li;He Jiaqing;Zhao Li-Dong
通讯作者：
Zhao Li-Dong
影响因子：
17.6
作者：
Qian Zhang;E. Chere;Yumei Wang;H. Kim;R. He;Feng Cao;K. Dahal;D. Broido;Gang Chen;Z. R
通讯作者：
Qian Zhang;E. Chere;Yumei Wang;H. Kim;R. He;Feng Cao;K. Dahal;D. Broido;Gang Chen;Z. R
影响因子：
27.8
作者：
G. Tan;C. Stoumpos;Si Wang;T. Bailey;Li-dong Zhao;C. Uher;M. Kanatzidis
通讯作者：
G. Tan;C. Stoumpos;Si Wang;T. Bailey;Li-dong Zhao;C. Uher;M. Kanatzidis
影响因子：
17.1
作者：
Yang, Ya;Pradel, Ken C.;Wang, Zhong Lin
通讯作者：
Wang, Zhong Lin
影响因子：
64.8
作者：
Biswas, Kanishka;He, Jiaqing;Kanatzidis, Mercouri G.
通讯作者：
Kanatzidis, Mercouri G.