Zero-Dimensional Plastic Phase Transition Iron-Based Compounds with High and Switchable SHG Responses.

Organic-inorganic hybrid materials have garnered significant interest due to their unique combination of phase transition characteristics, substantial entropy changes, simple preparation methods, and structural flexibility, making them promising candidates for applications in sensor technologies and data storage systems. In the present research, two plastic organic-inorganic hybrid phase transition materials: [CHNF]FeCl () and [CHNF]FeBr () were successfully synthesized by the H/F substitution strategy. Significant step-like dielectric changes were observed during the reversible phase transitions of (401 K) and (406 K).

Silver/Antimony-Base Multifunctional Double Perovskite with H/F Substitution Enhance Properties.

Two-dimensional double perovskites have experienced rapid development due to their outstanding optoelectronic properties and diverse structural characteristics. However, the synthesis of high-performance multifunctional compounds and the regulation of their properties still lack relevant examples. Herein, we synthesized two multifunctional compounds, (CHN)AgSbBr () and (F-CHN)AgSbBr (), which exhibit high solid-state phase transition temperature, bistable dielectric constant switching, second harmonic generation (SHG), and bright emission.

Investigating the Structure-property Relationships of Two Cd-based Hybrid Multifunctional Compounds with High Tc, Bright Fluorescence and Wide Band-gap.

Organic-inorganic hybrid multifunctional materials have shown significant application in lighting and sensor fields, owing to their prominent performance and diversity structures. Herein, we synthesized two multifunctional compounds: (propyl-quinuclidone) CdBr (1) and (F-butyl-quinuclidone) CdBr (2). By introducing light-emitting organic cation with flexible long chain, 1 and 2 exhibit excellent transition properties and bright blue-white fluorescence.

Halogen-regulating induced reversible high-temperature dielectric and thermal transitions in novel layered organic-inorganic hybrid semiconducting crystals.

Organic-inorganic hybrid metal halides for high-temperature phase transition have become increasingly popular owing to their wide operating temperature range in practical applications, , energy storage, permittivity switches and opto-electronic devices. This paper describes the subtle assembly of two new hybrid perovskite crystals, [Cl-CH-(CH)NH]CdX (X = Br 1; Cl 2), undergoing high- reversible phase transformations around 335 K/356 K. Differential scanning calorimetry (DSC), differential thermal analysis (DTA) and VT PXRD tests uncover their reversible first-order phase transition behaviors.

2-Chloroethylamine·trifluoromethanesulfonate combined with 18-crown-6: a ferroelectric with excellent dielectric switching properties.

Ferroelectric materials are not only important electronic functional materials, but also considered as the most promising intelligent basic materials, because they show good application prospects. Therefore, it is an urgent task to develop and explore new ferroelectric material systems. In addition, the most important feature of crown ethers is their ability to complex with positive ions, which is extremely useful in synthesis.

Excellent Switchable Properties, Broad-Band Emission, Ferroelectricity, and High in a Two-Dimensional Hybrid Perovskite: (4,4-DCA)PbBr Exploited by H/F Substitution.

Switchable materials have gained significant attention due to their potential applications in data storage, sensors, and switching devices. Two-dimensional (2D) hybrid perovskites have demonstrated promising prospects for designing switchable materials, where the dynamic motion of the organic components coupled with the distortion of the inorganic framework provides the driving force for triggering multifunctional switchable properties. Herein, through the H/F substitution strategy, we report a polar 2D hybrid lead-based perovskite, (4,4-DCA)PbBr (4,4-DCA = 4,4-difluorocyclohexylammonium) (), which exhibits dual-stable behavior in a dielectric and second harmonic generation (SHG) response during the reversible phase transition process near the high Curie temperature ∼ 409 K.

Zero-Dimensional Sn-Based Enantiomeric Phase-Transition Materials with High-Tc and Dielectric Switching.

The combination of chirality and phase-transition materials has broad application prospects. Therefore, based on the quasi-spherical theory and the thought strategy of introducing chirality, we have successfully synthesized a pair of chiral enantiomeric ligands (R/S)-triethyl-(2-hydroxypropyl)ammonium iodide, which can be combined with a tin hexachloride anion to obtain a pair of new organic-inorganic hybrid enantiomeric high-temperature plastic phase-transition materials: (R/S)-[CH CH(OH)CH N(CH CH ) ] SnCl (1-R/1-S), which have a high temperature phase transition of T =384 K, crystallize in the P2 chiral space group at room temperature, and have obvious CD signals. In addition, compounds 1-R and 1-S have a good low-loss dielectric switch and broadband gap.

Large Spontaneous Polarization Ferroelectric Property, Switchable Second-Harmonic Generation Responses, and Magnetism in an Fe-Based Compound.

Since the switchable spontaneous polarization of ferroelectric materials endows it with many useful properties such as a large pyroelectric coefficient, switchable spontaneous polarization, and semiconductor, it has a wide range of application prospects, and the research of high-performance molecular ferroelectric materials has become a hot spot. We obtained a 0D organic-inorganic hybrid ferroelectric [(CH)NCHCHCH]FeCl () with well-defined ferroelectric domains and excellent domain inversion and exhibited a relatively large spontaneous polarization ( = 9 μC/m) and a Curie temperature () of 394 K. Furthermore, compound belongs to the non-centrosymmetrical space group 2 and has a strong second-harmonic generation signal.

1D Chiral Lead Bromide Perovskite with Superior Second-Order Optical Nonlinearity, Photoluminescence, and High-Temperature Reversible Phase Transition.

Multifunctional materials are an attractive research area. Organic-inorganic hybrid perovskites are widely used in the design of these materials due to their rich properties and flexible composition. It is easy to obtain more photoelectric properties by introducing chiral groups as ligands.

High-T 1D Phase-Transition Semiconductor Photoluminescent Material with Broadband Emission.

One dimensional (1D) organic-inorganic halide hybrid perovskites have the advantages of excellent organic cation modifiability and diversity of inorganic framework structures, which cannot be ignored in the development of multi-functional phase-transition materials in photoelectric and photovoltaic devices. Here, we have successfully modified and synthesized an organic-inorganic hybrid perovskite photoelectric multifunctional phase-transition material: [C H ONCH F]⋅PbBr (1). The synergistic effect of the order double disorder transition of organic cations and the change of the degree of distortion of the inorganic framework leads to its high temperature reversible phase-transition point of T =374 K/346 K and its ultra-low loss high-quality dielectric switch response.

High-Tc Quadratic Nonlinear Optical and Dielectric Switchings in Fe-Based Plastic Crystalline Ferroelectric.

Plastic crystals, as a molecular material with multiple functions, have become a research hotspot in the exploration of new ferroelectric crystal compounds, especially due to their unique solid-solid phase transition properties. Based on this, we synthesized a new 0D organic-inorganic hybrid Fe-based plastic ferroelectric [(CH)NCHCHCH]FeCl (), which has a high-temperature phase transition point of 393 K, obvious ferroelectric domains, and spontaneous polarization and has been tested by dielectric and piezoelectric power microscopy (PFM) and ultraviolet absorption (UV-vis). At room temperature, it crystallizes in the space group 2 and has an obvious SHG switch.

Two Manganese(II)-Based Hybrid Multifunctional Phase Transition Materials with Strong Photoluminescence, High Quantum Yield, and Switchable Dielectric Properties: (CNH)MnBr and (CNH)MnBr.

Multifunctional materials have always been an attractive research area, but how to combine multiple excellent properties in one compound remains a considerable challenge. Organic-inorganic hybrid compounds are widely used in the design of such materials due to their rich properties and flexible assembly. Herein, two new manganese(II)-based organic-inorganic hybrid compounds, (CNH)MnBr () and (CNH)MnBr (), are prepared by the solution method.

Unusual symmetry breaking in high-temperature enantiomeric ferroelectrics with large spontaneous polarization.

Chiral organic-inorganic hybrid perovskites have gained extensive research interest due to their combination of chirality and the excellent optical, electrical and spin properties of perovskite materials, especially in two-dimensional hybrid perovskites. Herein, we report two-dimensional organic-inorganic perovskite enantiomeric ferroelectric [()-β-MPA]CdCl (1) and [()-β-MPA]CdCl (2) (MPA =methylphenethylammonium). Their mirror relationships are verified by both circular dichroism (CD) and crystal structures.

High-Temperature Phase Transition Containing Switchable Dielectric Behavior, Long Fluorescence Lifetime, and Distinct Photoluminescence Changes in a 2D Hybrid CuBr Perovskite.

A novel organic-inorganic hybrid perovskite crystal, [ClCH(CH)NH]CuBr (), having experienced an invertible high-temperature phase transition near (the Curie temperature = 355 K), has been successfully synthesized. The phase-transition characteristics for compound are thoroughly revealed by specific heat capacity (), differential thermal analysis, and differential scanning calorimetry tests, possessing 16 K broad thermal hysteresis. Multiple-temperature powder X-ray diffraction analysis further proves the phase-transition behavior of compound .

Neutral 1D Perovskite-Type ABX Phase Transition Material with a Narrowband Emission and Semiconductor Property.

Cyclic organic amines are emerging as excellent building blocks to assemble organic-inorganic hybrid phase transition materials due to their flexible cyclic structure. Here, we have assembled a 1D organic-inorganic hybrid dielectric material C H NOPbBr (1) by alloying the cyclic organic amine 3-hydroxypyridine. 1 displays a remarkable switchable dielectric response induced by an order-disorder transformation of the organic moiety, this transformation behaviour is confirmed by DSC and Hirshfeld surface measurements.

A multifunctional molecular ferroelectric with chiral features, a high Curie temperature, large spontaneous polarization and photoluminescence: (CHN)CdBr.

Low-dimensional chiral organic-inorganic hybrid metal halides have attracted a lot of attention in recent years due to their unique intrinsic properties, including having potential applications in optoelectronic and spintronic devices. However, low-dimensional chiral molecular ferroelectrics are very rare. In this paper, we report a novel zero-dimensional molecular ferroelectric (CHN)CdBr (CHN = protonated 3-phenylpropylamine), which has obvious dielectric and thermal anomalies and shows a high Curie temperature at 395 K.

Ferroelectric properties, narrow band gap and ultra-large reversible entropy change in a novel nonlinear ionic chromium(VI) compound.

A novel chromium(VI)-based compound, [(CHCH)N(CHCl)][CrOCl] (1), undergoes a high-temperature phase transition at around 340.9 K, accompanied by an ultra-large entropy change of 63.49 J mol K.

A Narrow Bandgap of 2D Ruddlesden-Popper Bilayer Perovskite with Giant Entropy Change and Photoluminescence.

The multifunctional two-dimensional (2D) organic-inorganic hybrid perovskites have potential applications in many fields, such as, semiconductor, energy storage and fluorescent device etc. Here, a 2D Ruddlesden-Popper (RP) perovskite (IPA) (FA)Pb I (1, IPA =C H NI , FA =CN H ) is determined for its photophysical properties. Strikingly, 1 reveals a solid reversible phase transition with T of 382 K accompanied by giant entropy change of 40 J mol  K .

High-Temperature and Large-Polarization Ferroelectric with Second Harmonic Generation Response in a Novel Crown Ether Clathrate.

Molecular ferroelectrics of high-temperature reversible phase transitions are very rare and have attracted increasing attention in recent years. In this paper is described the successful synthesis of a novel high-temperature host-guest inclusion ferroelectric: [(C H NF )(18-crown-6)][BF ] (1) that shows a pair of reversible peaks at 348 K (heating) and 331 K (cooling) with a heat hysteresis about 17 K by differential scanning calorimetry measurements, thus indicating that 1 undergoes a reversible structural phase transition. Variable-temperature PXRD and temperature-dependent dielectric measurements further prove the phase-transition behavior of 1.

Molecular Disorder Induces an Unusual Phase Transition in a Potential 2D Chiral Ferroelectric Perovskite.

Two-dimensional hybrid halide perovskites with single chiral and ferroelectricity together with various structural phase transitions provide the possibility for more diverse functional properties. Here, we present a 2D chiral hybrid halide perovskite ferroelectric, [C H (CH ) NH ] CdCl (4PBA-CdCl , 4PBA=4-phenylbutylamine) that experiences two continuous phase transitions from centrosymmetric triclinic P to polar chiral monoclinic P2 and then to another centrosymmetric tetragonal P4/mmm with increasing temperature, accompanied by symmetry breaking, due to the prominent octahedral distortion and disorder transformation of organic 4PBA cations. In the polar chiral phase, 4PBA-CdCl gives a significant CD signal and has a moderate ferroelectric polarization of 0.

Coupling Narrow Band Gap and Switchable SHG Responses in a New Molecule Ferroelectric: Imidazolyl Propylamine Pentabromo Stibium(III).

Due to the existence of some cross properties such as SHG (second-harmonic generation), ferroelectricity, piezoelectricity, and thermoelectricity, molecular ferroelectrics have been widely used as a composite multipurpose material. Particularly, organic-inorganic molecular ferroelectrics have received much interest recently because of their unique flexible structures, friendly environment, ease of synthesis, etc. Also, these hybrids show great flexibility in band-gap engineering.

Chiral Switchable Low-Dimensional Perovskite Ferroelectrics.

Low-dimensional hybrid organic-inorganic perovskites (HOIPs) possess more localized electronic states and narrower conduction and valence bands to promote self-trapping of excitons and stronger exciton emission; therefore, they are widely used as building blocks for various applications in the fields of optoelectronics, photovoltaics, light-emitting diodes, luminescence, fluorescence, and so forth. Despite the past decades of intensive study, the discovered low-dimensional chiral HOIPs are rare as of the 1D chiral HOIP single crystals reported in 2003, as well as the low-dimensional chiral HOIP ferroelectrics are particularly scarce since the first chiral two-dimensional (2D) and/or one-dimensional (1D) HOIP ferroelectrics reported. Herein, two new low-dimensional HOIPs with the same conformational formula [R-MPA]CdCl (R-MPA = ()-(-)-1-methyl-3-phenylpropylamine) were successfully synthetized by means of regulating the stoichiometric proportion of R-MPA and CdCl in two ways of 1:1 () and 2:1 ().