Dehydration-activated structural phase transition in a two-dimensional hybrid double perovskite

Abstract

As a feasible lead-free scheme, organic-inorganic hybrid double perovskite shows many excellent properties, including ferroelectricity, ferroelasticity, self-powered circularly polarized light detection and so on. In this work, the solid-to-solid structural...

Reversible Phase Transition and Second-Harmonic Response Based on a Zero-Dimensional Organic–Inorganic Hybrid Compound

“…Among these reports, the phase transition is mainly caused by the order–disorder arrangement of organic ammonium cations, which provide a potential strategy to find new multifunctional OIHMs by adjusting organic ammonium cations. Meanwhile, in previously reported phase change materials, organic ammonium cations fill in poles created by the inorganic framework, such as [NH 4 ]­[M­(HCOO) 3 ] and [C 6 H 14 N] 2 PbBr 4 . Therefore, by introducing new organic and inorganic frameworks, OIHMs with more new attractive properties could be obtained. − …”

Tin-based organic–inorganic metal halides with a reversible phase transition and thermochromic response

“…40 In addition, our group synthesized the compound (CASD) 2 MnBr 4 (CASD = 8-chloro-5-azonia-spiro [4.5] decane), which exhibits a large SHG response. 33 Currently, most of the organic-inorganic phase transition perovskites reported are based on lead (Pb), [41][42][43] antimony (Sb), 37 bismuth (Bi), 44,45 cadmium (Cd), [46][47][48] and manganese (Mn). [49][50][51] In spite of this, there are still some problems associated with potential toxicity and environmental pollution, which limit the further applications of these materials.…”

Water-driven Successive Structural Transformation in a Two-Dimensional (2D) Lead-Free Hybrid Double Perovskite

“…In HOIPs, various temperature-dependent structural phase transformations, such as single-crystal-to-single-crystal (SCSC) transformations, are readily driven by the continuous reorientation process of alkyl amine groups, ,, rotation of aromatic amine groups , and/or distorted MX 6 4– networks. − Besides, structural symmetry breaking in SCSC transformations also exert a significant effect on the design of second-harmonic generation (SHG), ferroelectrics, − and so on . Since the co-crystallization of water in HOIPs can not only induce the structural transition from zero to three dimensions but also change optoelectronic properties and thermochromic behavior, symmetry breaking induced by water molecules could make more sense. However, HOIPs tend to absorb moisture, and the crystal quality is often significantly decreased during hydration–dehydration, which makes detecting the structure difficult.…”

“…To our knowledge, water-induced SCSC transformation with symmetry breaking is relatively rare among previous 2D perovskites compounds . Herein, a lead-free 2D double perovskite with 4-(aminomethyl) piperidine (4-AMP), (C 6 H 16 N 2 ) 2 AgBiBr 8 ·H 2 O ( 1 ), was reported.…”