Probing Optoelectronic and Thermoelectric Properties of Lead-Free Perovskite SnTiO₃: HSE06 and Boltzmann Transport Calculations

Abstract

In order to develop a useful material for the optoelectronic sector with a variety of uses in thermoelectric and optical properties at a reasonable price, we researched SnTiO3, a Pb-free and Sn-based perovskite. We used the most recent density functional theory (DFT) methods, such as the gradient approximation (GGA) approach and the screened hybrid functional (HSE06). The calculated electronic structure yields to an indirect band gap of 2.204 eV along with two different K-points such as (X-Γ) using HSE06. The accomplished optical properties have been examined by dispersion, absorption, reflection, optical conductivity, and loss function against photon energy. The thermoelectric properties and electronic fitness function (EFF) were predicted DFT along with the Boltzmann transport theory. The Seebeck coefficient (S) and related thermoelectric properties such as electronic/thermal conductivity and the Hall coefficient were calculated as a function of chemical potential and carrier density (electrons and holes concentration) for room temperature. It was established that the temperature increases the Seebeck coefficient (S) at every hole carrier concentration. SnTiO3 has good EFF at 300, 500, and 800 K as well. The discovered EFF suggests that this material’s thermoelectric performance rises with temperature and can also be improved through doping. These findings demonstrated the potential of SnTiO3 as an n-type or p-type thermoelectric material depending on the doping.

Keywords

• lead-free perovskite
• HSE06@DFT band structure
• optical spectrum
• thermoelectric properties
• Hall coefficient
• electronic fitness function