A High Seebeck Voltage Thermoelectric Module with P‐type and N‐type MAPbI3 Perovskite Single Crystals

Abstract In recent years, organic–inorganic hybrid halide perovskite materials have been found to have low thermal conductivity and a large Seebeck effect, giving them great potential for thermoelectric applications. More stable single crystals make this possible. In this work, high‐quality MAPbI 3 single crystals are prepared using a modified solvent engineering method, and their trap density is as low as 2.5 × 10 9 cm −3 . It is noticed that the reaction between the crystal a metal electrode causes different degrees of doping effect along the vertical direction, leading to an increase in the intrinsic P‐type with Au metal, and forming N‐type semiconductor characteristics with Ag metal. A high Seebeck voltage thermoelectric module is obtained by combining the perovskite single crystal with different conductive characteristics. After device optimization, the thermoelectric potential of the champion module reaches a high voltage of 337 mV at 115 °C, the maximum output power with load reaches about 30 nW, and the theoretical maximum power reaches 65 nW. It is hoped that this research can promote the development of low thermal conductivity perovskite materials in the thermoelectric field.