A Near-Room-Temperature Hybrid Organic–Inorganic Lead Halide Perovskite Ferroelectric [BrCH₂CH₂N(CH₃)₃][PbBr₃] and Its Flexible Composite Film

Abstract

A hybrid organic–inorganic lead halide perovskite, [BrCH2CH2N­(CH3)3]­[PbBr3] (BEPbBr), obtained by matching a quasi-spherical (2-bromoethyl) trimethylammonium cation with an infinite one-dimensional zigzag [PbBr3]− anion chain, exhibits a reversible ferroelectric phase transition at 302/286 K. Switchable dielectric and ferroelectricity were observed accompanied by the order–disorder phase transition at near-room-temperature. Further, the ferroelectric BEPbBr was dispersed into a PVDF matrix to form flexible BEPbBr@PVDF composite films. The β-phase PVDF content in composite films was significantly improved without requiring complicated after-treatment, and the ferroelectricity was also greatly enhanced resulting from the induced ordered orientation by the interactions between BEPbBr and β-phase dominated PVDF. This finding may promote research on near-room-temperature multifunctional switching smart materials and wearable devices by utilizing molecular ferroelectrics and their flexible films.

Design, synthesis, and characterization of a new hybrid organic–inorganic perovskite with a high-Tc dielectric transition

“…The single crystal X-ray diffraction data of 1 were collected at 296 K and 410 K. At 296 K, 1 crystallizes in the monoclinic crystallographic system and is a 4 H -hexagonal perovskite structure as reported in many references. 25,26,28,29 The centrosymmetric space group of 1 is P 2 1 / c and the cell parameters of 1 is a = 10.8678(4) Å, b = 35.6850(15) Å, c = 7.7853(3) Å, Z = 8, β = 100.9530(10)° and V = 2964.3(2) Å 3 .…”

“…The single crystal X-ray diffraction data of 1 were collected at 296 K and 410 K. At 296 K, 1 crystallizes in the monoclinic crystallographic system and is a 4Hhexagonal perovskite structure as reported in many references. 25,26,28,29 The centrosymmetric space group of 1 is P2 It can be seen from the packing view (Fig. 2), every Pb atom lies on a 2 1 -screw axis and bridges with six Br atoms, forming infinite one-dimension [PbBr 3 ] − chains along the c-axis.…”

“…A handful of examples of perovskites containing [PbX 3 ] − can be found in the literature. 21,[24][25][26][27][28][29] It can be seen that a stepchange of ε′ is similar for all perovskites containing [PbX 3 ] − although they possess different cations or halogen atoms. As presented in Table S1, † (Et 4 N)PbBr 3 , (FTEA)PbBr 3 , IMPbBr 3 , CEPBBr 3 and BEPbBr 3 have a similar [PbBr 3 ] − structure and similar change of ε′ with 1.…”

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

“…The organic–inorganic hybrid materials (OIHMs) are a hot scientific topic due to their adjustable structure, easy synthesis, and functional features. − Compared with traditional pure organic or inorganic materials, OHIMs possess more advanced properties. − As one unique property of OHIMs, structural phase transition receives tremendous attention, which can introduce attractive properties, such as switchable dielectric and nonlinear optical switching. − Thus, the OHIMs have great application prospects such as data communications, optoelectronic equipment, memories, actuators, sensors, and capacitors. − …”

A new organic–inorganic hybrid perovskite ferroelectric [ClCH2CH2N(CH3)3][PbBr3] and Its PVDF matrix-assisted highly-oriented flexible ferroelectric films

“…Recently reported organic–inorganic hybrid one-dimensional perovskite [BrCH 2 CH 2 N(CH 3 ) 3 ][PbBr 3 ] exhibits near-room-temperature ferroelectricity. 33 The structure of hybrid metal halide perovskites can be tailored by changing the organic component, central metal, and halide ion. It has been found that the replacement of halide ions in perovskites containing [(CH 3 ) 3 NCH 2 X] (X = F, Cl, Br, I) is a useful method to meet the momentum matching and tailor ferroelectric properties.…”