Two Lead‐Free Organic‐Inorganic Hybrid Halides: Exploring Dielectric Switching and Photoluminescence Integrated in Crystals

Abstract Organic‐inorganic hybrid halides have attracted widespread attention in optics, electricity, magnetism. In particular, some of them can have a combination of luminescence and switching characteristics, providing a potential for a single device unit to meet multiple application requirements. Herein, we reported two novel organic‐inorganic hybrid single‐crystals (CTA) 2 ZnCl 4 ( 1 ; CTA=3‐chloro‐2‐hydroxypropyltrimethylammonium) and (CTA) 2 [InCl 5 (H 2 O)] ⋅ H 2 O ( 2 ), exhibiting long lifetime blue emission upon UV excitation. Systematic characterizations of the compounds including crystal structure, phase transition, thermal, and photoluminescence properties were carried out. DSC tests detected that 1 had a reversible phase transition accompanied by obvious heat anomaly, at 411/391 K on the heating/cooling process, leading to its good switchable dielectric response with striking anisotropy along various crystallographic axis. This work offered a new example on the effective design of multifunctional response materials.