Publication details
Elastic deformation suppresses ion demixing in mixed-halide perovskites
| Authors | |
|---|---|
| Year of publication | 2025 |
| Type | Article in Periodical |
| Magazine / Source | MATERIALS & DESIGN |
| MU Faculty or unit | |
| Citation | |
| web | https://www.sciencedirect.com/science/article/pii/S0264127525012705 |
| Doi | https://doi.org/10.1016/j.matdes.2025.114850 |
| Keywords | Mixed-halide perovskites; Spontaneous decomposition; Cahn-Hilliard equation |
| Description | We simulated the kinetics of ion demixing in mixed-halide perovskites using phenomenological Cahn-Hilliard equation. In the model we considered the chemical and the elastic parts of Helmholtz free energy of the perovskite lattice, as well as the effect of free carriers generated by sample illumination. If the demixing process is accompanied by local elastic deformation caused by the dependence of the lattice parameter on the local chemical composition, the elastic contribution to the free energy is larger than the other two parts so that elastic deformation effectively suppresses the ion segregation. The demixing can take place if the internal stresses are relieved by surface elastic relaxation, or if the deformation of the lattice is plastic like around structural defects or at grain boundaries. |