Work

Structural distortions control scaling of exciton binding energies in two-dimensional Ag/Bi double perovskites

Year: 2025

Type: article

Abstract: and Bethe-Salpeter Equation frameworks, we resolve this puzzle by systematically comparing experimental structures with idealized models designed to isolate the effects of octahedral distortions, interlayer separation, and stacking. We find that structural distortions, driven by directional Ag d orbital bonding, govern the momentum-space origin and character of the exciton, and are the primary cause of the observed non-monotonic trends. Furthermore, we explore how interlayer distance and stacking influence band gaps and exciton binding energies, showing that, despite different chemistry, the underlying confinement physics mirrors that of Pb-based 2D perovskites. Our results establish design principles for tuning excitonic properties in this broader class of layered, lead-free materials.

Source: Nanoscale

DOI: 10.1039/d5nr03010b

Authors: Pierre Lechifflart, Raisa-Ioana Biega, Linn Leppert

Institution: University of Twente

Language: English

Topic: Perovskite Materials and Applications

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Funders: U.S. Department of Energy, Partnership for Advanced Computing in Europe AISBL, Nederlandse Organisatie voor Wetenschappelijk Onderzoek, National Supercomputing Center, Korea Institute of Science and Technology Information