2026/02/16 by Dmytro Rak, Dušan Lorenc, Daniel M. Balazs +3 · 1 voice
Engineering · Materials Science · #Perovskite Materials and Applications #Chemical and Physical Properties of Materials #Ferroelectric and Piezoelectric Materials
paper · pdf · doi:10.1038/s41467-026-68660-5
openalex publication_date 2026/02/16 · openalex created_date 2026/02/17 · openalex updated_date 2026/07/29
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 localized flexoelectric fields spatially separate electrons and holes to opposite sides of domain walls, exponentially suppressing recombination. Domain walls thus act as efficient mesoscopic transport channels for long-lived photocarriers, microscopically linking structural heterogeneity to charge transport and offering mechanistically informed design principles for perovskite solar-energy technologies.