Bi-doped CH3NH3PbI3 effective masses and electronic properties research: A theoretical study using VASP

School of Mathematics and Physics, Huanggang Normal University, Newport NO.2 Road, Hubei, Huanggang, 438000, P. R. China

Adv. Mater. Lett., 2019, 10 (4), pp 275-278

DOI: 10.5185/amlett.2019.2232

Publication Date (Web): Jan 10, 2019

Copyright © IAAM-VBRI Press

E-mail: pengliping@hgnu.edu.cn

Abstract

We calculated the effective masses and electronic properties of Bi-doped CH₃NH₃PbI₃ perovskites as a thermoelectric material using the VASP functional. The Bismuth doping concentration of 11.1%, 20%, 33.3% corresponding band gaps are 1.46. 0.75, 0.56 eV, respectively. The effective masses of carriers and the band gaps decrease with the doping concentration addition. We found that the structure of Bi as an interstitial atom doped MAPbI₃ were much more stable than undoped one by the crystal systemic energy, and the Bi doping made the Fermi Level shift close to the bottom of conduction band, leading to charge carrier close to the Fermi level, resulted in the higher electrical conductivity. Moreover, Bi doping produced a smaller electron effective mass with doping concentration addition, increasing the MAPbI₃’s mobility. As a result, the Bi-doped MAPbI₃ could simultaneously enhance the electrical conductivity and Seebeck coefficient. Our results showed that Bi doped MAPbI₃ is a promising approach to develop thermoelectric and photovoltaic properties in organic-inorganic hybrid perovskite materials.

Keywords

Bi-doped MAPbI₃, effective masses, electrical conductivity, seebeck coefficient, fermi level.