Theoretical investigation on two-dimensional monofluorinating
phenethylammonium perovskite
Abstract
Detailed theoretical investigations on their structural and electronic
properties of two-dimensional (2D) monofluorinating phenethylammonium
perovskite are required to deeply understand the origin of the crystal
structural and optoelectronic differences caused by organic spacers.
Herein, formation energy, non-covalent interaction, band structure,
exciton binding energy, carrier mobility and optical absorption spectra
of 2D monofluorinating phenethylammonium lead iodide perovskite were
calculated using density functional theory. Results show that steric
effect leads to the orientational disorder of spacers in
ortho-fluorinating phenethylammonium perovskite and weak interaction
leads to the herringbone configuration of spacers in meta-fluorinating
phenethylammonium perovskite. Exciton binding energy significantly
influences the short circuit current density (JSC) of
fluorophenethylammonium-based 2D perovskites, which can well explain the
experimental trends of JSC. Formation energy analysis of perovskites
with the same chemical components but different crystal structures and
exciton binding energy calculation can be additional strategies in
high-throughput screening for high-performance 2D perovskites.