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 MAPbI3 single crystals are prepared using a modified solvent engineering method, and their trap density is as low as 2.5 × 109 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.

Doping of Sn-based two-dimensional perovskite semiconductor for high-performance field-effect transistors and thermoelectric devices

“…The highest PF value we have achieved is about 3.92 μW m −1 K −2 at the doping ratio of 5 mol %. A summary of previously reported PF values as a function of electrical conductivities for 3D and 2D OIHP semiconductors at room temperature (RT), including MAPbX 3 (X denotes the halide ions) ( Haque et al., 2019 ; Long et al., 2019 ; Mettan et al., 2015 ; Tang et al., 2020 ; Wu et al., 2018 ; Xie et al., 2021 ; Xiong et al., 2019 ; Ye et al., 2017 ), MASnI 3 ( Hao et al., 2014 ; Haque et al., 2020a ), (PEA) 2 MA 2 Sn 3 I 10 ( Yang et al., 2021 ), and (4Tm) 2 FASn 2 I 7 ( Hsu et al., 2021 ), is shown in Figure 4 D. It is seen that the PF value we have achieved in (PEA) 2 SnI 4 by SnI 4 doping is among the highest ones ( Hsu et al., 2021 ; Yang et al., 2021 ). It is also notable that Sn-based OIHPs, which generally have higher σ than Pb-based OIHPs, exhibit higher PF values, suggesting that Sn-based OIHPs are very attractive for high-performance TE devices.…”

Enhanced room-temperature terahertz detection and imaging derived from anti-reflection 2D perovskite layer on MAPbI3 single crystals

“…For comparison, the performance of the devices with Au electrodes is also measured in Fig. S13,† exhibiting an unfavorable p-type character, 47,48 where the energy level hinders rather than facilitates thermal-induced carrier transport. 49…”

“…Thus, Ag is selected as the electrode material since it can react with halide ions to form anion vacancies, resulting in majority carriers of electrons. 47,48 The stability of MAPbI 3 with Ag electrodes is presented in Fig. S12.…”

“…† For comparison, the performance of the devices with Au electrodes is also measured in Fig. S13, † exhibiting an unfavorable p-type character, 47,48 where the energy level hinders rather than facilitates thermal-induced carrier transport. 49 To better understand the working mechanism, a schematic illustration of the thermoelectric effect in our device is displayed in Fig.…”

Further Advancement of Perovskite Single Crystals

“…(b) Thermal voltage and Seebeck coefficient of MAPbI 3 SCs with Au or Ag electrodes. Reprinted with permission from ref . Copyright 2021 John Wiley and Sons.…”