Article
Engineering, Environmental
Ruonan Min, Yanxia Wang, Xue Jiang, Rongchun Chen, Huijun Kang, Enyu Guo, Zongning Chen, Xiong Yang, Tongmin Wang
Summary: By doping Nb into ZrNiSn-based compounds, the thermoelectric and mechanical properties have been significantly improved, with enhanced power factor and reduced thermal conductivity. This research demonstrates the potential for industrial applications.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Engineering, Environmental
Rongchun Chen, Quanwei Jiang, Lifeng Jiang, Ruonan Min, Huijun Kang, Zongning Chen, Enyu Guo, Xiong Yang, Tongmin Wang
Summary: Entropy engineering is an effective strategy to decrease the lattice thermal conductivity of half-Heusler alloys (HHs). However, the suboptimal applications of entropy engineering in medium-entropy HHs hinder the optimization of their thermoelectric properties. This study reports a systematic synthesis and analysis of ZrCoSb-based medium-entropy HHs, revealing the scattering of atomic disorder as the main factor for decreased lattice thermal conductivity. Density functional theory calculations attribute the lower Seebeck coefficients to the lower density-of-states effective mass and the slowly changing density-of-states at the Fermi level. Optimization of the spark plasma sintering temperature achieved an ultralow lattice thermal conductivity and improved power factor in the Zr0.6(NbTa)0.4CoSb medium-entropy HH alloy, resulting in the highest peak figure-of-merit value of -0.42.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Soumya Ranjan Mishra, Li Ping Tan, Vikrant Trivedi, Manjusha Battabyal, P. S. Sankara Rama Krishnan, Durga Venkata Maheswar Repaka, Satyesh Kumar Yadav, Raju Vijayaraghavan Ramanujan, Budaraju Srinivasa Murty
Summary: The effect of doping on the thermoelectric properties of HH HEA Ti2NiCoSnSb was studied. Sb doping reduced thermal conductivity. Mass scattering by heavy (Ta, Zr) and light (Al) dopants was studied to further lower thermal conductivity. Zr-doped samples showed high HH phase content and low-lattice thermal conductivity of 1.9 W/(m·K). The poor solubility of Ta enhanced electrical properties. NiAl phase in Al-doped samples improved the power factor value significantly. A maximum ZT of 0.29 was achieved in all doped systems, with an optimum dopant level of Zr (25%), Ta (7.5%), and Al (10%).
ACS APPLIED ENERGY MATERIALS
(2023)
Article
Chemistry, Physical
Nagendra S. Chauhan, Yuzuru Miyazaki
Summary: The study demonstrates the effectiveness of using isoelectronic heavy elemental substitutions to enhance thermoelectric transport. Bismuth substitution for antimony in VFeSb half-Heusler material enhances the electrical power factor near room temperature and lowers the lattice thermal conductivity.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Crystallography
Junhong Wei, Yongliang Guo, Guangtao Wang
Summary: In this study, the electronic structure and properties of ScRhTe were investigated using density functional theory calculations. It was found that ScRhTe is a narrow-band-gap semiconductor, with higher Seebeck coefficient and power factor for n-type doping. The pressure has a significant effect on the band gap and properties of ScRhTe, with improved thermoelectric properties under compressive pressure and improved optical properties under tensile pressure.
Article
Physics, Applied
Kaiyang Xia, Chaoliang Hu, Chenguang Fu, Xinbing Zhao, Tiejun Zhu
Summary: Half-Heusler compounds with 18 valence electrons are considered promising high-temperature thermoelectric materials, while nominal 19-electron compounds have gained popularity due to their unexpected high performance. The focus is now on the discovery and challenges of cation-deficient 19-electron half-Heusler compounds with vacancy-related short-range order, offering insights into defect-tailored thermoelectric properties.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Chongbin Liang, Bushra Jabar, Chen Liu, Yuexing Chen, Zhuanghao Zheng, Ping Fan, Fu Li
Summary: The effect of iodine substitution on the thermoelectric transport properties of Te-free compound Bi2SeS2 was studied. It was found that the electrical conductivity was enhanced and the lattice thermal conductivity was reduced after iodine substitution, resulting in an improved power factor and enhanced thermoelectric performance for the material.
Article
Chemistry, Inorganic & Nuclear
Rahidul Hasan, Yan Gu, Se Yun Kim, Dong Won Chun, Kyu Hyoung Lee
Summary: A simple and scalable compositional tuning method is proposed to enhance the thermoelectric conversion efficiency (ZT) of double half-Heusler (DHH) materials by generating full-Heusler (FH) nanoprecipitates. The results reveal that FH nanoprecipitates can substantially intensify the phonon scattering and achieve an ultra-low lattice thermal conductivity of about 0.9 W m(-1) K(-1) at 973 K in Ti2FeNiSb2. Additionally, the presence of FH nanoprecipitates improves the electronic transport properties by filtering low-energy carriers.
INORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Physical
Xiaoling Zhang, Shuang Li, Bo Zou, Pengfei Xu, Yilin Song, Biao Xu, Yifeng Wang, Guodong Tang, Sen Yang
Summary: By utilizing grain boundary engineering, the thermoelectric performance of half-Heusler compounds can be significantly improved through increased Seebeck coefficient and power factor, as well as reduced lattice thermal conductivity.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Physical
Qingmei Wang, Xiaodong Xie, Shan Li, Zongwei Zhang, Xiaofang Li, Honghao Yao, Chen Chen, Feng Cao, Jiehe Sui, Xingjun Liu, Qian Zhang
Summary: This research prepared pseudo-ternary Ti(Fe, Co, Ni)Sb-based half-Heusler alloys with both n-type and p-type components by using Co as the amphoteric dopants, leading to significantly increased power factors and peak ZT values at 973 K. The enhanced performance was attributed to the higher carrier concentration and effective mass, as well as the decreased lattice thermal conductivity induced by alloying Hf on the Ti site.
JOURNAL OF MATERIOMICS
(2021)
Article
Materials Science, Multidisciplinary
Chu-Kun Dai, Qing-Feng Song, Li Xie, Rui-Heng Liu, Sheng-Qiang Bai, Li-Dong Chen
Summary: Optimization of carrier concentration through Sb doping enhances the power factor and zT value of ZrPtSn half-Heusler compounds, making them suitable for high-temperature thermoelectric applications. However, the effect of Ni alloying mainly reduces lattice thermal conductivity, with the final zT value not showing significant superiority in ZrPtSn0.92Sb0.08 sample.
Article
Materials Science, Multidisciplinary
L. Huang, T. Liu, A. Huang, G. Yuan, J. Wang, J. Liao, X. Lei, Q. Zhang, Z. Ren
Summary: The effects of Nb and Sb deficiencies on the phase composition and thermoelectric properties of NbCoSb have been studied, showing that intrinsic vacancy defects can significantly improve the thermoelectric performance. Experimental results demonstrate that introducing vacancy defects can double the ZT value to 0.8 in Nb0.97CoSb0.99, highlighting the effectiveness of this strategy in enhancing the thermoelectric properties of some half-Heusler alloys.
MATERIALS TODAY PHYSICS
(2021)
Article
Chemistry, Inorganic & Nuclear
Feng Gao, Ying Lei, Yu Li, Jin Qiu, Chao Yong, Nan Wang, Guangyuan Song, Huaichuan Hu
Summary: TiNiSn1-xSbx thermoelectric bulks were fabricated using microwave synthesis combined with spark plasma sintering and annealing process. The high density of the samples was confirmed through physical phase analysis and microstructure characterization. Antimony doping and annealing process significantly improved the electrical properties of the TiNiSn-based materials and maintained low lattice thermal conductivity. TiNiSn0.965Sb0.035 achieved a maximum power factor of 3125.9 mu Wm(-1)K(-2) at 873 K and a total thermal conductivity of 4.2-4.7 W m(-1)K(-1), with a maximum ZT value of 0.57, which is 86% higher than that of the undoped sample.
JOURNAL OF SOLID STATE CHEMISTRY
(2023)
Article
Materials Science, Multidisciplinary
Ying Lei, Yu Li, Run-Dong Wan, Wen Chen, Hong-Wei Zhou
Summary: TiNiSn-based half-Heusler HfxTi1-xNiSn0.97Sb0.03 bulks with high relative densities were successfully synthesized through microwave synthesis and sintering. The phase composition and microstructure were characterized, and the thermoelectric properties were measured. The results showed the nearly single phase existence after microwave sintering, and the grain sizes and grain boundaries were influenced by Hf-doping. The maximum figure of merit of 0.46 was obtained for Hf0.1Ti0.9NiSnSn0.97Sb0.03 at 723 K.
Article
Chemistry, Physical
Yang Liu, Xiuting Xu, Wei Fang, Sukai Teng, Xinjian Xie, Linyang Li, Shanshan Fan, Jun Li, Jia Li
Summary: The TiFe0.5Ni0.5Sb compound with special quasi-random structure (SQS) was modeled using the 18-electron rule, showing a nonmagnetic indirect band gap semiconductor with a band gap of 0.45 eV. Its lattice thermal conductivity decreases with increasing temperature, while the dimensionless figure of merit ZT at 1390 K is evaluated to be 0.35, higher than its parent compound. The theoretical prediction for TiFe0.5Ni0.5Sb can simulate experimental results and potentially improve the TE performance of disordered alloys using the 18-electron rule.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
