Self-healing, where a modification in some parameter is reversed with time without any external intervention, is one of the particularly interesting properties of halide perovskites. While there are a number of studies showing such self-healing in perovskites, they all are carried out on thin films, where the interface between the perovskite and another phase (including the ambient) is often a dominating and interfering factor in the process. Here, self-healing in perovskite (methylammonium, formamidinium, and cesium lead bromide (MAPbBr3, FAPbBr3, and CsPbBr3)) single crystals is reported, using two-photon microscopy to create damage (photobleaching) ≈110 µm inside the crystals and to monitor the recovery of photoluminescence after the damage. Self-healing occurs in all three perovskites with FAPbBr3 the fastest (≈1 h) and CsPbBr3 the slowest (tens of hours) to recover. This behavior, different from surface-dominated stability trends, is typical of the bulk and is strongly dependent on the localization of degradation products not far from the site of the damage. The mechanism of self-healing is discussed with the possible participation of polybromide species. It provides a closed chemical cycle and does not necessarily involve defect or ion migration phenomena that are often proposed to explain reversible phenomena in halide perovskites.
Self-Healing Inside APbBr3 Halide Perovskite Crystals / D.R. Ceratti, Y. Rakita, L. Cremonesi, R. Tenne, V. Kalchenko, M. Elbaum, D. Oron, M.A.C. Potenza, G. Hodes, D. Cahen. - In: ADVANCED MATERIALS. - ISSN 0935-9648. - 30:10(2018 Mar 08).
|Titolo:||Self-Healing Inside APbBr3 Halide Perovskite Crystals|
|Parole Chiave:||bleaching; halide perovskites; photoluminescence; self-healing; self-repair; materials science (all); mechanics of materials; mechanical engineering|
|Settore Scientifico Disciplinare:||Settore FIS/03 - Fisica della Materia|
|Data di pubblicazione:||8-mar-2018|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1002/adma.201706273|
|Appare nelle tipologie:||01 - Articolo su periodico|