Zhang Jiawei, Song Lirong, Madsen Georg K H, Fischer Karl F F, Zhang Wenqing, Shi Xun, Iversen Bo B
Center for Materials Crystallography, Department of Chemistry and iNANO, Aarhus University, Langelandsgade 140, Aarhus DK-8000, Denmark.
Computational Materials Discovery, ICAMS, Ruhr-Universität Bochum, Bochum 44801, Germany.
Nat Commun. 2016 Mar 7;7:10892. doi: 10.1038/ncomms10892.
Thermoelectric technology, which possesses potential application in recycling industrial waste heat as energy, calls for novel high-performance materials. The systematic exploration of novel thermoelectric materials with excellent electronic transport properties is severely hindered by limited insight into the underlying bonding orbitals of atomic structures. Here we propose a simple yet successful strategy to discover and design high-performance layered thermoelectric materials through minimizing the crystal field splitting energy of orbitals to realize high orbital degeneracy. The approach naturally leads to design maps for optimizing the thermoelectric power factor through forming solid solutions and biaxial strain. Using this approach, we predict a series of potential thermoelectric candidates from layered CaAl2Si2-type Zintl compounds. Several of them contain nontoxic, low-cost and earth-abundant elements. Moreover, the approach can be extended to several other non-cubic materials, thereby substantially accelerating the screening and design of new thermoelectric materials.
热电技术在回收工业废热作为能源方面具有潜在应用，这需要新型高性能材料。对具有优异电子传输性能的新型热电材料进行系统探索，因对原子结构的潜在键合轨道缺乏深入了解而受到严重阻碍。在此，我们提出一种简单却成功的策略，通过最小化轨道的晶体场分裂能以实现高轨道简并度，来发现和设计高性能层状热电材料。该方法自然地引出了通过形成固溶体和双轴应变来优化热电功率因子的设计图。利用这种方法，我们从层状CaAl2Si2型津特耳化合物中预测出一系列潜在的热电候选材料。其中几种含有无毒、低成本且储量丰富的元素。此外，该方法可扩展到其他几种非立方材料，从而大幅加速新型热电材料的筛选和设计。
