Revealing the Intrinsic Electronic Structure of 3D Half‐Heusler Thermoelectric Materials by Angle‐Resolved Photoemission Spectroscopy

Autor: Chenguang Fu, Mengyu Yao, Xi Chen, Lucky Zaehir Maulana, Xin Li, Jiong Yang, Kazuki Imasato, Fengfeng Zhu, Guowei Li, Gudrun Auffermann, Ulrich Burkhardt, Walter Schnelle, Jianshi Zhou, Tiejun Zhu, Xinbing Zhao, Ming Shi, Martin Dressel, Artem V. Pronin, G. Jeffrey Snyder, Claudia Felser
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Zdroj: Advanced Science, Vol 7, Iss 1, Pp n/a-n/a (2020)
Druh dokumentu: article
ISSN: 2198-3844
DOI: 10.1002/advs.201902409
Popis: Abstract Accurate determination of the intrinsic electronic structure of thermoelectric materials is a prerequisite for utilizing an electronic band engineering strategy to improve their thermoelectric performance. Herein, with high‐resolution angle‐resolved photoemission spectroscopy (ARPES), the intrinsic electronic structure of the 3D half‐Heusler thermoelectric material ZrNiSn is revealed. An unexpectedly large intrinsic bandgap is directly observed by ARPES and is further confirmed by electrical and optical measurements and first‐principles calculations. Moreover, a large anisotropic conduction band with an anisotropic factor of 6 is identified by ARPES and attributed to be one of the most important reasons leading to the high thermoelectric performance of ZrNiSn. These successful findings rely on the grown high‐quality single crystals, which have fewer Ni interstitial defects and negligible in‐gap states on the electronic structure. This work demonstrates a realistic paradigm to investigate the electronic structure of 3D solid materials by using ARPES and provides new insights into the intrinsic electronic structure of the half‐Heusler system benefiting further optimization of thermoelectric performance.
Databáze: Directory of Open Access Journals
Nepřihlášeným uživatelům se plný text nezobrazuje