Intrinsic and Extrinsic Charge Transport in CH3 NH3 PbI3 Perovskites Predicted from First-Principles

Abstract

Both intrinsic and extrinsic charge transport properties of methylammonium lead triiodide perovskites are investigated from first-principles. The weak electron-phonon couplings are revealed, with the largest deformation potential (∼ 5 eV) comparable to that of single layer graphene. The intrinsic mobility limited by the acoustic phonon scattering is as high as a few thousands cm2 V-1 s-1 with the hole mobility larger than the electron mobility. At the impurity density of 10 18 cm-3, the charged impurity scattering starts to dominate and lowers the electron mobility to 101 cm2 V-1 s-1 and the hole mobility to 72.2 cm 2 V-1 s-1. The high intrinsic mobility warrants the long and balanced diffusion length of charge carriers. With the control of impurities or defects as well as charge traps in these perovskites, enhanced efficiencies of solar cells with simplified device structures are promised.