Issue 31, 2023

How fast do defects migrate in halide perovskites: insights from on-the-fly machine-learned force fields

Abstract

The migration of defects plays an important role in the stability of halide perovskites. It is challenging to study defect migration with experiments or conventional computer simulations. The former lacks an atomic-scale resolution and the latter suffers from short simulation times or a lack of accuracy. Here, we demonstrate that machine-learned force fields, trained with an on-the-fly active learning scheme against accurate density functional theory calculations, allow us to probe the differences in the dynamical behaviour of halide interstitials and halide vacancies in two closely related compositions CsPbI3 and CsPbBr3. We find that interstitials migrate faster than vacancies, due to the shorter migration paths of interstitials. Both types of defects migrate faster in CsPbI3 than in CsPbBr3. We attribute this to the less compact packing of the ions in CsPbI3, which results in a larger motion of the ions and thus more frequent defect migration jumps.

Graphical abstract: How fast do defects migrate in halide perovskites: insights from on-the-fly machine-learned force fields

  • This article is part of the themed collection: Perovskites

Associated articles

Supplementary files

Article information

Article type
Communication
Submitted
27 feb 2023
Accepted
22 mar 2023
First published
22 mar 2023
This article is Open Access
Creative Commons BY-NC license

Chem. Commun., 2023,59, 4660-4663

How fast do defects migrate in halide perovskites: insights from on-the-fly machine-learned force fields

M. Pols, V. Brouwers, S. Calero and S. Tao, Chem. Commun., 2023, 59, 4660 DOI: 10.1039/D3CC00953J

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements