Collective behavior of molecular dipoles in CH3NH3PbI3 - Charles Goehry
Place: Reykjavik University, Room M113
Time: Wednesday 20 May 15:00-16:00
Speaker: Charles Goehry, Reykjavik University
Abstract: Solar cells based on organic perovskite materials have recently attracted a lot of attention. The talk will have two parts. In the first part we describe ab-initio molecular dynamics of the thermal motion occurring in CH3NH3PbI3. We use the data generated by the code Siesta to obtain estimates of the rotational relaxation time of the methyl-ammonium cations (CH3NH+3 ). The PbI6 cage and the cations interact and perform collective motion. We qualitatively describe the formation of microscopic ferroelectric domains. In the second part of the talk we show electrical characteristics of a solar cell containing CH3NH3PbI3 deposited on a TiO2 surface. The photo-conversion efficiency can increase if the band gap of CH3NH3PbI3 could slightly decrease.
Organizer: Andrei Manolescu on behalf of the Nanophysics Center.