First Principles Study of Nernst Effect in 2D Materials

The rapidly growing demand for replacing fossil fuels with clean energy harvesting methods necessitates research in renewable energy generation and management. Two-dimensional materials have attracted much attention in energy conversion applications due to their unique transport properties, more enticingly, when a thermoelectric power factor greater than 5 was reported in Fe₂V_0.8W_0.2Al thin films[1]. Similar to the Seebeck effect, the ratio of the developed voltage to the temperature gradient in the presence of a magnetic field is called the Nernst effect[2] which has been utilized in cryogenic cooling[3], thermopile systems[4], and radiation detector applications[5]. The Nernst effect was observed in Bismuth for the first time and then further studied in semiconductors such as silicon, germanium, and indium antimonide. The Nernst effect in topological semimetals has been of focused interest, more recently. However, data of the Nernst coefficient of 2D materials has been very limited. Here, we present on large-scale screening of 2D structures using high-throughput density functional theory (DFT) calculations to discover promising new materials candidates with high Nernst coefficients. Our preliminary theoretical results show that some 2D materials could exhibit relatively considerable Nernst coefficients. The discovery of new ultra-high Nernst coefficient 2D materials (larger than Bismuth) could pave the way towards more efficient radiation detectors and more productive cryogenic cooling designs.<br/><br/>References<br/>[1] B. Hinterleitner <i>et al.</i>, “Thermoelectric performance of a metastable thin-film Heusler alloy,” <i>Nature 2019 576:7785</i>, vol. 576, no. 7785, pp. 85–90, Nov. 2019, doi: 10.1038/s41586-019-1751-9.<br/>[2] S. E. Rezaei, M. Zebarjadi, and K. Esfarjani, “First-principles-aided evaluation of the Nernst coefficient beyond the constant relaxation time approximation,” <i>Comput Mater Sci</i>, vol. 225, p. 112193, Jun. 2023, doi: 10.1016/J.COMMATSCI.2023.112193.<br/>[3] S. Bogason, J. Heremans, and A. Sandip Mazumder, “Cryogenic Cooling with a Single Crystal Bismuth Nernst-Ettingshausen Cooler,” 2018, Accessed: Jun. 11, 2023. [Online]. Available: https://kb.osu.edu/handle/1811/86859<br/>[4] M. Mizuguchi and S. Nakatsuji, “Energy-harvesting materials based on the anomalous Nernst effect,” <i>http://www.tandfonline.com/action/journalInformation?show=aimsScope&journalCode=tsta20#.VmBmuzZFCUk</i>, vol. 20, no. 1, pp. 262–275, Jan. 2019, doi: 10.1080/14686996.2019.1585143.<br/>[5] H. J. Goldsmid and K. R. Sydney, “A thermal radiation detector employing the Nernst effect in Cd3As2-NiAs,” <i>J Phys D Appl Phys</i>, vol. 4, no. 6, p. 869, Jun. 1971, doi: 10.1088/0022-3727/4/6/319.