A novel p-type half-Heusler from high-throughput transport and defect calculations
A novel p-type half-Heusler from high-throughput transport and defect calculations
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DOI：
10.1039/c6tc04259g
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发表时间：
2016-12-21
影响因子：
6.4
通讯作者：
Madsen, Georg K. H.
中科院分区：
文献类型：
--
作者：
Bhattacharya, Sandip;Madsen, Georg K. H.
在这项工作中，我们使用高通量技术确定了p型半赫斯勒热电候选者。多个描述符用来评价输运性质、元素丰度和热力学稳定性。我们确定了已知的(V/Nb/Ta)FeSb和(Zr/Hf)CoSb化合物，以及一个新的鼓舞人心的(Nb/Ta)CoSN半Heusler系统。然后，我们使用最先进的缺陷热化学计算来排除任何内在的掺杂限制，然后预测每个候选者的非本征掺杂。我们证明缺陷计算与已知系统的现有实验符合得很好，其中我们还提供了实现p掺杂的新途径。对于(Nb/Ta)CoSN系统，第四族过渡金属(Ti，Zr，Hf)被预测为实现其作为高性能p型半-Heusler热电材料的特定掺杂选择。我们还用分子轨道理论分析了半-Heusler的电子结构，以了解良好的p型输运性质的起源。
In this work we identify p-type half-Heusler thermoelectric candidates using high-throughput techniques. Multiple descriptors are used to evaluate transport properties, elemental abundancies and thermodynamic stabilities. We identify the known (V/Nb/Ta)FeSb and (Zr/Hf)CoSb compounds as well as a novel encouraging (Nb/Ta)CoSn half-Heuslers system. We then use state of the art defect thermochemistry calculations to rule out any intrinsic doping limitations and thereafter predict extrinsic dopants for each candidates. We demonstrate that the defect calculations agree well with existing experiments for the known systems, where we also provide new routes to achieve p-doping. For the (Nb/Ta)CoSn system, group IV transition metals (Ti,Zr,Hf) are predicted as the specific dopant choices to realize their potential as high-performance p-type half-Heusler thermoelectrics. The electronic structure of the half-Heuslers are also analysed using molecular orbital theory to understand the origins of favorable p-type transport properties.