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Thermoelectric materials possess the potential for refrigeration and power generation due to their ability to directly convert heat and electricity. Carrier mobility and the Seebeck coefficient are key properties of thermoelectric materials. Improving the effective mass is the most effective and frequent way to optimize the Seebeck coefficient. However, carrier mobility deteriorates dramatically with increasing effective mass and thus limits further improvement of thermoelectric performance. Here, the focus is on the importance of modifying the scattering factor (r) to enhance the electrical properties, and it is found that the anisotropic scattering factor enhances the carrier mobility and Seebeck coefficient of anion‐doped n‐type tin selenide crystals along the out‐of‐plane direction, indicating the potential of modifying r to improve electrical properties. Following this strategy, the average dimensionless figure of merit (ZTave) for iodine‐doped SnSe crystals is significantly improved from 0.84 to 1.57 in 300–773 K. The results emphasize the critical role of scattering factor and propose a new perspective for enhancing carrier mobility, providing a novel strategy to optimize thermoelectric performance. [ABSTRACT FROM AUTHOR]

The recent growing energy crisis draws considerable attention to high‐performance thermoelectric materials. n‐type bismuth telluride is still irreplaceable at near room temperature for commercial application, and therefore, is worthy of further investigation. In this work, nanostructured Bi2Te3 polycrystalline materials with highly enhanced thermoelectric properties are obtained by alkali metal Na solid solution. Na is chosen as the cation site dopant for n‐type polycrystalline Bi2Te3. Na enters the Bi site, introducing holes in the Bi2Te3 matrix and rendering the electrical conductivity tunable from 300 to 1800 Scm–1. The solid solution limit of Na in Bi2Te3 exceeds 0.3 wt%. Owing to the effective solid solution, the Fermi level of Bi2Te3 is properly regulated, leading to an improved Seebeck coefficient. In addition, the scattering of both charge carriers and phonons is modulated, which ensured a high‐power factor and low lattice thermal conductivity. Benefitting from the synergistic optimization of both electrical and thermal transport properties, a maximum figure of merit (ZT) of 1.03 is achieved at 303 K when the doping content is 0.25 wt%, which is 70% higher than that of the pristine sample. This work disclosed an effective strategy for enhancing the performance of n‐type bismuth telluride‐based alloy materials. [ABSTRACT FROM AUTHOR]

Seebeck coefficient is a crucial parameter in the field of thermoelectricity as it directly impacts the output power of thermoelectric devices. Intrinsic SnTe thermoelectrics exhibit excellent electrical conductivity but suffer from its low Seebeck coefficient, significantly impeding the advancement of the performance in both materials and devices. Herein, we focus on improving the Seebeck coefficient to favor the output voltage and power of SnTe thermoelectrics. Through a stepwise optimization strategy involving carrier concentration modulation and energy band convergence, we have substantially improved the performance of p-type SnTe thermoelectrics and enhanced the Seebeck coefficient across the entire temperature range. An ultrahigh Seebeck coefficient exceeding 103 μV K−1 at ambient temperature, a highest ZT value of 1.3 at 823 K, and a maximum ZT ave of ∼ 0.7 among 300–823 K were obtained in the Sn 0.82 Mn 0.18 Bi 0.03 Te 0.91 I 0.09 sample. Our study provides a universal strategy for advancing SnTe-based thermoelectrics and enhancing the power generation performance, which can be well broadened and implemented in various thermoelectric systems. [Display omitted] [ABSTRACT FROM AUTHOR]