ds-Block Element-Enabled Cooperative Regulation of Electrical and Thermal Transport for Extraordinary N- and P-Type PbSe Thermoelectrics near Room Temperature
ds-Block Element-Enabled Cooperative Regulation of Electrical and Thermal Transport for Extraordinary N- and P-Type PbSe Thermoelectrics near Room Temperature
复制标题
DOI：
10.1021/acs.chemmater.1c04123
复制
发表时间：
2022-01
影响因子：
8.6
通讯作者：
Dan Zhang;Fang Xu;Lei Yang;Shikang Gao;Xingyuan San;Jianglong Wang;Junyou Yang;Yubo Luo;Shufang Wang
中科院分区：
文献类型：
--
作者：
Dan Zhang;Fang Xu;Lei Yang;Shikang Gao;Xingyuan San;Jianglong Wang;Junyou Yang;Yubo Luo;Shufang Wang
从实际应用的角度来看，在一个系统中实现n型和p型的高热电性能是特别期望的。在这里，我们提供了一种新的策略，将DS块元件（S），以实现前所未有的高热电性能的n型和p型PbSe接近室温。Cu填隙和Cd合金化的协同效应，包括通过平坦化导带来提高有效质量，通过保护电荷传导通道来保持高载流子迁移率，以及通过位错抑制声子输运，使得n型PbSe在300-523 K范围内的平均ZT达到创纪录的0.81。此外，在300-523 K的范围内，Ag掺杂的p型PbSe中实现了0.67的创纪录的高平均ZT，这是由于（i）有效质量、载流子浓度和迁移率的协同优化以及（ii）增强的点缺陷散射。最终，在ΔT= 223 K下，在由所开发的PbSe系统制成的热电模块中实现了6.4%的高理论转换效率，这与商业Bi 2 Te 3的转换效率相当。我们的工作表明，引入ds-块元件将PbSe扩展到近室温发电应用，并使所开发的材料非常适合与在中间温度下工作的其他广泛报道的高性能PbSe热电体分割，这对于在宽温度范围内应用低成本PbSe基热电器件可能非常重要。
From a practical application perspective, achieving a high thermoelectric performance for both n and p types in one system is particularly desirable. Here, we provide a new strategy for incorporating the ds-block element(s) to realize an unprecedentedly high thermoelectric performance for both n-type and p-type PbSe near room temperature. The synergistic effects of the Cu interstitial and Cd alloying, including enhancing the effective mass by flattening the conducting band, maintaining a high carrier mobility by protecting the charge-conducting channel, and suppressing phonon transport via dislocations, enable a record high averageZTof 0.81 in the range of 300–523 K for n-type PbSe. Moreover, a record high averageZTof 0.67 in the range of 300–523 K is achieved in Ag-doped p-type PbSe due to (i) the cooperative optimization of the effective mass, carrier concentration, and mobility and (ii) the strengthened point defect scattering. Ultimately, a high theoretical conversion efficiency of 6.4%, which is comparable to that of commercial Bi2Te3, is thereby achieved in the thermoelectric module made of as-developed PbSe systems at ΔT= 223 K. Our work demonstrates that introducing the ds-block element(s) extends PbSe to near room temperature power generation application and makes as-developed materials very suitable for segmentation with other widely reported high-performance PbSe thermoelectrics working at intermediate temperature, which can be greatly significant for the application of a low-cost PbSe-based thermoelectric device across a broad temperature range.