Investigations on the Thermoelectric Transport Properties in the Hole‐doped La2CuO4

Abstract

AbstractCompared with the traditional thermoelectric semiconductors, the research progress of thermoelectric oxides with high‐temperature thermal stability is far behind. In this work, a layered copper oxide La2CuO4 was synthesized by combining the high‐energy ball milling, solid state reaction and spark plasma sintering. By introducing metal elements (Ba, Sr, Pb) at La site, the increased carrier concentration with optimized electrical transport properties were achieved in La2CuO4‐based thermoelectric oxides. Results showed that Ba has the best doping effect among the three dopants, with an optimal carrier concentration of ∼1020 cm−3. Furthermore, the figure of merit (ZT) value was enhanced over the entire temperature range with a maximum ZTave of ∼0.03 at 300–923 K, which is nearly two orders of magnitude higher than that of printine La2CuO4. Our research has successfully developed the thermoelectric properties of La2CuO4‐based oxide, which has the great potential to be a reliable candidate as the thermocouple for high‐temperature detection in the key parts of aircrafts.