Perovskites for Solar Thermoelectric Applications: A First Principle Study of CH₃NH₃AI₃ (A = Pb and Sn)

Hybrid organic/inorganic CH₃NH₃AI₃ (A = Pb and Sn) perovskites have been recognized as promising photovoltaic materials. Using ab initio calculations, we showed that these systems may also be promising materials for solar thermoelectric applications. We found that their large carrier mobilities mainly originate from a combination of the small effective masses of electrons and holes and a relatively weak carrier–phonon interaction. We propose that by tuning the carrier concentration to values of the order of ∼10¹⁸cm^–3, the thermoelectric figure of merit of Sn and Pb based perovskites may reach values ranging from 1 to 2, which could possibly be further increased by optimizing the lattice thermal conductivity through engineering perovskite superlattices