Sebastia-Luna Paz, Pokharel Unnati, Huisman Bas A H, Koster L Jan Anton, Palazon Francisco, Bolink Henk J
Instituto de Ciencia Molecular, ICMol, Universidad de Valencia, 46980 Paterna, Spain.
Zernike Institute for Advanced Materials, University of Groningen, 9747 AG Groningen, The Netherlands.
ACS Appl Energy Mater. 2022 Aug 22;5(8):10216-10223. doi: 10.1021/acsaem.2c01936. Epub 2022 Jul 26.
Most current thermoelectric materials have important drawbacks, such as toxicity, scarceness, and peak operating temperatures above 300 °C. Herein, we report the thermoelectric properties of different crystalline phases of Sn-based perovskite thin films. The 2D phase, CsSnI, is obtained through vacuum thermal deposition and easily converted into the black β phase of CsSnI (B-β CsSnI) by annealing at 150 °C. B-β CsSnI is a p-type semiconductor with a figure of merit (ZT) ranging from 0.021 to 0.033 for temperatures below 100 °C, which makes it a promising candidate to power small electronic devices such as wearable sensors which may be interconnected in the so-called Internet of Things. The B-β phase is stable in nitrogen, whereas it spontaneously oxidizes to CsSnI upon exposure to air. CsSnI shows a negative Seebeck coefficient and an ultralow thermal conductivity. However, the ZT values are 1 order of magnitude lower than for B-β CsSnI due to a considerably lower electrical conductivity.
目前大多数热电材料都存在重要缺陷，如毒性、稀缺性以及高于300°C的峰值工作温度。在此，我们报告了锡基钙钛矿薄膜不同晶相的热电性能。二维相CsSnI通过真空热沉积获得，并在150°C退火时容易转化为CsSnI的黑色β相（B-β CsSnI）。B-β CsSnI是一种p型半导体，在低于100°C的温度下，其优值（ZT）范围为0.021至0.033，这使其成为为小型电子设备（如可穿戴传感器）供电的有前途的候选材料，这些设备可能在所谓的物联网中相互连接。B-β相在氮气中稳定，而暴露在空气中会自发氧化为CsSnI。CsSnI显示出负的塞贝克系数和超低的热导率。然而，由于电导率低得多，其ZT值比B-β CsSnI低1个数量级。
