Radiation-Sensitive Layered Hybrid Double Perovskites Driven by a Dual-Ion-Woven Supramolecular Framework for X-ray Tomography.

Abstract

A promising candidate for X-ray detection is layered hybrid double perovskites (LHDPs) with excellent structural stability, but their sensitivity is generally limited by unsatisfactory interlayer charge transport. Herein, employing one ethylenediamine (EDA) chain as a structural inducer, we successfully obtain unusual Dion-Jacobson (DJ) phase LHDPs, (EDABr)4AgBiBr8 and (EDABr)4CuBiBr8, featuring a Ruddlesden-Popper-like (RP-like) interlayer. Thanks to the bridging of bromine anions, organic cations are linked via charge-assisted hydrogen bonds, where two ionic spacers are orderly woven into a supramolecular framework. Consequently, the RP-like interlayer space is regulated by the dual-ion-woven supramolecular framework with embedded charge-assisted hydrogen bond networks, remarkably enriching interlayer interactions and boosting charge transport. Through theoretical calculations, structural roles of the supramolecular framework are elucidated by extra orbital contribution and large diffusion barrier of Br anions. As proof of concept, the sensitivity of RP-like devices up to 5250 μC Gyair-1cm-2 is a record-high of LHDP-based X-ray detectors for now, while a low detection limit (91 nGyair s-1) and outstanding radiation-resistant capability (50 Gyair) are achieved. Moreover, an oriented membrane device is prepared to demonstrate high-performance X-ray tomography. These findings offer a brand-new interlayer-modulation strategy for the construction of sensitive and stable scintillation semiconductors.