title: Enhancing the carrier thermalization time in organometallic perovskites by halide mixing.
abstract: Hybrid metal-organic halide perovskites have recently attracted a great deal of attention because of their interesting electronic, optical and transport properties, which make them promising materials for high-performance, low-cost solar cells. Fundamental understanding of the formation mechanisms and dynamics of photoinduced charge carriers is essential for improving the performance of perovskite solar cell devices. For example, a significant amount of absorbed solar energy is lost as a result of carrier thermalization. This energy could be harnessed by extracting hot carriers before they cool down to the band edges. Although such hot carrier collection is experimentally challenging, theoretical investigations based on time-dependent methods can guide future experimental research by providing insights into the thermalization process. Here, we perform ab initio nonadiabatic molecular dynamics simulations to study non-radiative relaxation dynamics of charge carriers in hybrid halide perovskites. We find that the carrier relaxation time can be considerably increased by mixing halogen atoms in the perovskite materials. These findings show that simple approaches could be adopted to slow down the thermalization process of hot carriers in perovskite materials.
authors.affiliation: Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, PO Box 5825, Doha, Qatar. mmadjet@qf.org.qa.
authors.forename: Mohamed El-Amine
authors.initials: Mel-A
authors.lastname: Madjet
authors.affiliation: Department of Chemistry, University at Buffalo, Buffalo, State University of New York, NY 14260-3000, USA. alexeyak@buffalo.edu.
authors.forename: Alexey V
authors.initials: AV
authors.lastname: Akimov
authors.affiliation: Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, PO Box 5825, Doha, Qatar. mmadjet@qf.org.qa.
authors.forename: Fadwa
authors.initials: F
authors.lastname: El-Mellouhi
authors.affiliation: Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, PO Box 5825, Doha, Qatar. mmadjet@qf.org.qa.
authors.forename: Golibjon R
authors.initials: GR
authors.lastname: Berdiyorov
authors.affiliation: Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, PO Box 5825, Doha, Qatar. mmadjet@qf.org.qa.
authors.forename: Sahel
authors.initials: S
authors.lastname: Ashhab
authors.affiliation: Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, PO Box 5825, Doha, Qatar. mmadjet@qf.org.qa.
authors.forename: Nouar
authors.initials: N
authors.lastname: Tabet
authors.affiliation: Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, PO Box 5825, Doha, Qatar. mmadjet@qf.org.qa and Department of Chemistry, Physics and Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Sabre
authors.initials: S
authors.lastname: Kais