At 180 K, the data are equally well fitted by third-order kinetics.Interestingly, at 80 K, the kinetics appear to be fourth order. This work is licensed under a Creative Commons Attribution 4.0 International License.These results are reproducible from two other samples and reflect incomplete transition from the tetragonal high temperature to the orthorhombic low-temperature crystal structure due to the constraints given by the disordered inhomogeneous film. The authors declare no competing financial interests. Marcus or Maria-Elisabeth Michel-Beyerle or Elbert E. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material.
The latter parameters indicate how many free carriers move away from their origin, and how fast, before loss mechanisms such as carrier recombination occur.
For the perovskite films studied in this paper, our analysis reveals a significant contribution from backscattering of charge carriers due to disorder.
Analysis of the time evolution of the carrier density via a rate equation allows us to extract the absolute values of the rate constants and not only their lower bounds.
For the description of n(τ), we use the rate equation (Equation 2) to analyse the dynamics that is attributed to the recombination of charge carriers: Equation (2) involves multiple-order recombination mechanisms providing different channels for the decrease of free-carrier density.
Our fit contains four fitting parameters: the initial carrier density n a trimolecular process, for example, Auger recombination involving electron and hole and a third free carrier where two of the particles lose energy with respect to each other while a third particle gains energy, and so the total energy is conserved in this three-particle process.