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With the increasing research on giant dielectric materials, there is growing interest in the development of switching materials with giant dielectric properties. In this study, a novel organic–inorganic hybrid material (Et3NC2H4Br)FeCl4 was synthesized. It was characterized through differential scanning calorimetry (DSC) and in situ temperature-dependent powder X-ray diffraction (PXRD), which determined its phase transition temperature (TC) to be 362 K. Temperature-dependent dielectric measurements revealed that the material exhibited switchable dielectric properties, with the real part of the dielectric constant exceeding 106 at 500 Hz and a dielectric switching ratio surpassing 103. The ratio refers to the ratio between the high dielectric state and the low dielectric state of a step-like dielectric anomaly. Single-crystal X-ray diffraction (SCXRD) analysis confirmed that the material crystallized in the P21/c space group with a zero-dimensional structure. The optical bandgap, determined through UV-visible spectroscopy, was calculated to be 2.62 eV. Additionally, analysis using Hirshfeld surfaces and 2D fingerprint plots revealed that the predominant intermolecular interactions are H⋯Cl and H⋯H interactions. This study is anticipated to provide insights and hope for the design and application of high-temperature giant dielectric switching materials. [ABSTRACT FROM AUTHOR]

The impact of molecular point groups on phase transition materials has been seldom discussed. Two organic cations with different symmetries were incorporated into a [SnCl6]2− framework. By breaking the symmetry of cations, a novel hybrid material with two successive phase transitions featuring a rare "on–off–on" nonlinear optical switch was obtained. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid perovskite materials have garnered considerable interest due to their potential in optoelectronic applications. Herein, we assemble a novel one-dimensional organic–inorganic hybrid perovskite from the organic cation with trans-configuration, (trans-4-methylcyclohexylammonium)CdCl3 (compound 1), which undergoes successive high-temperature structural phase transitions accompanied by dual switchable dielectric anomalies. The variable-temperature structural analyses indicate that the phase transition from the triclinic P1¯ to the monoclinic space group P21/c at 385 K is driven by the swinging motion of half organic cations, while the subsequent transition to the orthorhombic space group Cmcm at 436 K is attributed to the order–disorder transformation of all organic cations. Moreover, compound 1 exhibits semiconducting characteristics and blue light emission with a remarkably long lifetime of 9.94 ns. These findings are poised to inspire the design of novel multifunctional hybrid perovskites with superior performance. [ABSTRACT FROM AUTHOR]

In recent years, phase change materials (PCMs) have received extensive attention because of their applications in many fields, such as construction, semiconductor, energy and intelligent response switch. Organic‐inorganic hybrid materials (OIHMs) are wide applied in the preparation of PCMs due to their controllability of organic and inorganic components. In this study, we successfully synthesized an organic‐inorganic hybrid material (BTTD)MnCl4 (compound 1, BTTD=[(CH3)2NCH2Cl(CH2)3CH2ClN(CH3)2]. The purity of compound 1 was confirmed by PXRD. The crystal structure of compound 1 was analyzed at 300 K, 381 K and 400 K. The three different crystal structures prove the phase change of compound 1. According to the result of differential scanning calorimeter (DSC), the phase transition of compound 1 is reversible. Moreover, the measured bandgap (Eg) of 1 is 2.25 eV. The dielectric constant of compound 1 fluctuates near 370 K, indicating the changes of electrical properties, so compound 1 can be used to cut off circuit. This temperature is close to the boiling point of water under standard ambient conditions. Therefore, this work provides a new direction for the design of intelligent response switch for electric kettle. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) have drawn increasing attention for their promising applications in thermal switches, data communication, and energy storage. Because of the complexity of the interactions between molecules, it is still a challenge to design PCMs with a desired high phase transition temperature (Tc). In this study, a one-dimensional hybrid perovskite of (TEACCl)PbBr3 (1, TEACCl = Et3NCH2Cl) was successfully designed and synthesized with a Tc = 390 K. Disordering of TEACCl+ on the heating process is the origin of the structural phase transition of 1 from the P21/c to P63/mmc structure. It is noted that the phase transition is associated with an excellent switchable dielectric property, which indicates that 1 has the potential to be applied to sensor equipment. After calculation, 1 is an infrequent indirect bandgap semiconductor with an energy gap of 3.57 eV. Moreover, 1 exhibits strong red fluorescence under irradiation of UV light. This work will provide guidance for designing high Tc switching materials. [ABSTRACT FROM AUTHOR]

With the increasing research on giant dielectric materials, there is growing interest in the development of switching materials with giant dielectric properties. In this study, a novel organic-inorganic hybrid material (Et 3 NC 2 H 4 Br)FeCl 4 was synthesized. It was characterized through differential scanning calorimetry (DSC) and in situ temperature-dependent powder X-ray diffraction (PXRD), which determined its phase transition temperature ( T C ) to be 362 K. Temperature-dependent dielectric measurements revealed that the material exhibited switchable dielectric properties, with the real part of the dielectric constant exceeding 10 6 at 500 Hz and a dielectric switching ratio surpassing 10 3 . The ratio refers to the ratio between the high dielectric state and the low dielectric state of a step-like dielectric anomaly. Single-crystal X-ray diffraction (SCXRD) analysis confirmed that the material crystallized in the P 2 1 / c space group with a zero-dimensional structure. The optical bandgap, determined through UV-visible spectroscopy, was calculated to be 2.62 eV. Additionally, analysis using Hirshfeld surfaces and 2D fingerprint plots revealed that the predominant intermolecular interactions are H⋯Cl and H⋯H interactions. This study is anticipated to provide insights and hope for the design and application of high-temperature giant dielectric switching materials.

The impact of molecular point groups on phase transition materials has been seldom discussed. Two organic cations with different symmetries were incorporated into a [SnCl 6 ] 2- framework. By breaking the symmetry of cations, a novel hybrid material with two successive phase transitions featuring a rare "on-off-on" nonlinear optical switch was obtained.

Antiferroelectric (AFE) materials, characterized by double electric hysteresis loops, can be transformed to the ferroelectric (FE) phase under an external electric field, making them promising candidates for electronic energy storage and solid-state refrigeration. Additionally, the field-induced strain in AFE materials is contingent upon the direction of the electric field, rendering it with a switching characteristic. Although AFE materials have made progress in the field of energy storage and negative electrocaloric effect, the coexistence of AFE and ferroelasticity is still rarely reported. Here, two isomorphic organic-inorganic hybrid perovskites, HDAEPbCl 4 and HDAEPbBr 4 (HDAE is [2-(hydroxydimethylammonio)ethan-1-aminium]), exhibiting FE-AFE-PE (PE is paraelectric) phase transitions, are presented. Remarkably, the temperature range where AFE and ferroelasticity coexist is significantly broadened from 59.9 K to 115.1 K by strengthening short-range forces via halogen substitution. This discovery extends the family of FE, AFE, and ferroelastic materials, contributing to the development of multifunctional materials and advancing multifunctional material development., (© 2024 Wiley‐VCH GmbH.)

Phase change materials (PCMs) have drawn increasing attention for their promising applications in thermal switches, data communication, and energy storage. Because of the complexity of the interactions between molecules, it is still a challenge to design PCMs with a desired high phase transition temperature ( T c ). In this study, a one-dimensional hybrid perovskite of (TEACCl)PbBr 3 (1, TEACCl = Et 3 NCH 2 Cl) was successfully designed and synthesized with a T c = 390 K. Disordering of TEACCl + on the heating process is the origin of the structural phase transition of 1 from the P 2 1 / c to P 6 3 / mmc structure. It is noted that the phase transition is associated with an excellent switchable dielectric property, which indicates that 1 has the potential to be applied to sensor equipment. After calculation, 1 is an infrequent indirect bandgap semiconductor with an energy gap of 3.57 eV. Moreover, 1 exhibits strong red fluorescence under irradiation of UV light. This work will provide guidance for designing high T c switching materials.