Thermoelectric properties of layered oxyselenides with 3d transition metal ions
Yueyang Yang, Zhifang Zhou, Bin Wei, Junyan Liu, Jinle Lan, Mingchu Zou, Yushuai Xu, Yunpeng Zheng, Ce‐Wen Nan, Yuanhua Lin
Abstract
Abstract Layered oxychalcogenides have received extensive attention in the fields of magnetism, superconductivity, lithium battery, and luminescence due to their unique electronic, magnetic properties, and layered structure, among which layered oxyselenides have excellent and promising thermoelectric performance, such as BiCuSeO and Bi 2 LnO 4 Cu 2 Se 2 . Here, we successfully synthesized Sr 2 MO 2 Cu 2 Se 2 (M = Co, Ni, Zn) and Sr 2 FeO 3 CuSe and investigated the thermoelectric properties at a wide temperature range (298–923 K). They have a relatively high Seebeck coefficient (>300 μV K −1 ) in medium to high temperature range and possess a low thermal conductivity. The power factor and ZT reach 65 μW m −1 K −1 and 0.07 at 923 K for intrinsic Sr 2 NiO 2 Cu 2 Se 2 , and a higher performance is expected to be achieved by strategies like carrier concentration optimization and band structure engineering.