Composition-Dependent Thermoelectric Properties of Hybrid Tin Perovskites (CH3NH3)xCs1-xSnI3: Insights into Electrical and Thermal Performance

TL;DR

This study systematically explores how the composition of hybrid tin perovskites affects their electrical and thermal properties, revealing optimal mixes for thermoelectric performance and emphasizing microstructural control.

Contribution

It provides new insights into the composition-dependent thermoelectric properties of hybrid perovskites, highlighting the importance of microstructure and composition optimization for improved performance.

Findings

Intermediate MA+ content yields high power factor and zT up to 0.06.

MASnI3 shows promising low-temperature thermoelectric performance with zT of 0.10.

Composition influences electrical conductivity and Seebeck coefficient balance.

Abstract

This work presents a comprehensive investigation of the thermoelectric properties of bulk hybrid perovskites with the general formula MAxCs1-xSnI3 (0 < x < 1). A series of bulk samples were synthesized and systematically characterized to explore the relationship between composition, microstructure, and thermoelectric performance. Compositions with intermediate MA+ content (x = 0.2 and x = 0.5) show an optimal balance between electrical conductivity and Seebeck coefficient, yielding high power factor values (0.6 - 0.7 muW/cmK2 at 423 K) and favorable thermoelectric performance with zT values up to 0.06. In contrast, compositions with MA+ contents (x = 0, x = 0.6, and x = 0.8) exhibit lower thermoelectric performance due to reduced Seebeck coefficients or suppressed conductivity. MASnI3 shows promising low-temperature thermoelectric performance with a maximum $zT$ of 0.10 at 423 K, attributed to its rapidly increasing Seebeck coefficient. These findings highlight the importance of microstructural control and composition optimization in the development of hybrid perovskites for thermoelectric applications.