Organic molecular dynamics and charge-carrier lifetime in lead iodide perovskite MAPbI<sub>3</sub>.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 35046035.
- Also identified by DOI 10.1073/pnas.2115812119 and PMC identifier 8795553.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
The long charge carrier lifetime of the hybrid organic-inorganic perovskites (HOIPs) is the key for their remarkable performance as a solar cell material. The microscopic mechanism for the long lifetime is still in debate. Here, by using a muon spin relaxation technique that probes the fluctuation of local magnetic fields, we show that the muon depolarization rate (Δ) of a prototype HOIP methylammonium lead iodide (MAPbI<sub>3</sub>) shows a sharp decrease with increasing temperature in two steps above 120 K and 190 K across the structural transition from orthorhombic to tetragonal structure at 162 K. Our analysis shows that the reduction of Δ is quantitatively in agreement with the expected behavior due to the rapid development of methyl ammonium (MA) jumping rotation around the <i>C</i> <sub>3</sub> and <i>C</i> <sub>4</sub> symmetry axes. Our results provide direct evidence for the intimate relation between the rotation of the electric dipoles of MA molecules and the charge carrier lifetime in HOIPs.