Flexoelectric domain walls enable charge separation and transport in cubic perovskites.

ABSTRACT: The exceptional energy-harvesting efficiency of lead-halide perovskites arises from unusually long photocarrier diffusion lengths and recombination lifetimes that persist even in defect-rich, solution-grown samples. Paradoxically, perovskites are also known for having very short exciton decay times. Here, we resolve this apparent contradiction by showing that key optoelectronic properties of perovskites can be explained by localized flexoelectric polarization confined to interfaces between domains of spontaneous strain. Using birefringence imaging, electrochemical staining, and zero-bias photocurrent measurements, we visualize the domain structure and directly probe the associated internal fields in nominally cubic single crystals of methylammonium lead bromide. We demonstrate that localiz

SUBMITTER: Rak D 

PROVIDER: S-EPMC12909952 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature