121st General Meeting of the KCS

Type Oral Presentation
Area Oral Presentation for Young Scholars in Physical Chemistry
Room No. Room 402
Time THU 10:12-:
Code PHYS.O-7
Subject Methylammonium Lead Iodide Photochemistry probed by Raman microscopy and fs pump-probe spectroscopy
Authors Myeongkee Park
Department of Chemistry, Dong-A University, Korea
Abstract There has been tremendous interest in how methylammonium lead iodide (MAPbI3) perovskite achieves high photovoltaic efficiency as a future promising solar cell. Many of studies, particularly, have been tried to understand flexible MA ion’s roles in the inorganic Pb-I framework, e.g. MA-induced polaron-screening and transient Rashba splitting effects. Recently, we have experimentally found mechanistic findings for MA’s role by employing Raman & photoluminescence microscopy, femtosecond time-resolved spectroscopy, and first-principles density functional theory. Our results suggest that (1) MA’s dipole orientational changes induce distortions of the Pb-I framework via hydrogen-bonding strength changes between the hydrogen of MA and the iodine atom and (2) excited-state coherent phonon modes of the Pb-I framework are correlated with distorted structures indicating the isolated polaron formation.
E-mail femtoguy@gmail.com