Rational Design of 2D Metal Halide Perovskites with Low Congruent Melting Temperature and Large Melt-Processable Window

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(13), С. 9272 - 9284

Опубликована: Март 22, 2024

Metal halide perovskites (MHPs) have garnered significant attention due to their distinctive optical and electronic properties, coupled with excellent processability. However, the thermal characteristics of these materials are often overlooked, which can be harnessed cater diverse application scenarios. We showcase efficacy lowering congruent melting temperature (Tm) layered 2D MHPs by employing a strategy that involves modification flexible alkylammonium through N-methylation I-substitution. Structural–property analysis reveals I-substitution play pivotal roles in reducing hydrogen bond interactions between organic components inorganic parts, rotational symmetry number cation restricting residual motion cations. Additional I···I enhance intermolecular lead improved molten stability, as evidenced higher viscosity. The discussed this study exhibit low Tm wide melt-processable windows, e.g., (DMIPA)2PbI4 showcasing 98 °C large window 145 °C. was further validated when applied bromine-substituted MHPs. Lowering enhancing stability hold great promise for various applications, including glass formation, preparation high-quality films photodetection, fabrication devices.

Язык: Английский

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A Polar Two-Dimensional Lead-Free Hybrid Perovskite for Self-Powered Polarization-Sensitive Photodetection

Inorganic Chemistry Frontiers, Год журнала: 2024, Номер 11(15), С. 4611 - 4618

Опубликована: Янв. 1, 2024

The first polar 2D lead-free hybrid perovskite (4BrPEA) 3 BiI 6 was synthesized by reducing the occupancy rate of Bi 3+ ions, and self-powered polarization-sensitive photodetector achieved a large photocurrent anisotropy factor 2.16.

Язык: Английский

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A one-dimensional organic-inorganic hybrid ferroelectric exhibiting dielectric-optical duple switch

Journal of Materials Chemistry C, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

A one-dimensional organic – inorganic hybrid ferroelectric, (C 4 H 8 NH 2 ) [BiCl 5 ], exhibiting a dielectric-optical duple switch is reported. Theoretical study discloses that the ferroelectricity originates from both cations and anions.

Язык: Английский

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An Opto‐Iontronic Cholesteric Liquid Crystalline Retina for Multimodal Circularly Polarized Neuromorphic Vision

Advanced Materials, Год журнала: 2025, Номер unknown

Опубликована: Март 3, 2025

Abstract Circularly polarized light (CPL) is fundamental to phase‐controlled imaging, quantum optics, and optical computing. Conventional CPL detection, relying on polarizers quarter‐wave plates, complicates device design reduces sensitivity. Among emerging detectors, organic field‐effect transistors (OFET) with helical semiconductors are highly promising due their compact structures but suffer tedious synthesis, low dissymmetric factors ( g ph < 0.1), high operating voltages (> 50 V). To address these issues, an opto‐iontronic cholesteric liquid crystalline i ‐CLC) film developed that both electrically photonically active, serving as the dielectric in phototransistors. The well‐defined structure broadly tunable pitches of ‐CLC enable it detect excellent “handedness” selectivity across a broad spectrum. Moreover, its ionic nature provides capacitance (up 580 nF cm − 2 @20 Hz). resulting flexible detectors achieve unprecedentedly dissymmetry factor = 1.33) at (< 5 V), showcasing significant potential communication data encryption. Furthermore, leveraging , they can perform in‐sensor computing for accurate semantic segmentation using fused multimodal visual inputs (e.g., circularly ordinary light), achieving accuracy 75.73% mean intersection over union 0.3982, surpassing performance non‐CPL photodetectors. Additionally, optimizes power consumption by 10 compared most conventional processing systems, offering groundbreaking hardware solution high‐performance neuromorphic vision.

Язык: Английский

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Coupled Kite-to-Square Distortion Transition and Physical Properties in 2D Lead Halide Perovskite

The Journal of Physical Chemistry Letters, Год журнала: 2024, Номер 15(31), С. 7979 - 7991

Опубликована: Июль 30, 2024

2D lead halide perovskites showcase diverse electrical and optoelectrical properties due to their adaptable structural distortion, which dictates the symmetry characteristics of material. To accommodate geometric shape cation, inorganic layer perovskite often undergoes specific distortions such as lead–halide bond length elongation/compression atom displacement. The resultant distortion manifests a quadrilateral formed by Pb atoms from four adjacent octahedrons. degree increases deviates further square vice versa. This not only visually represents magnitude but also confirms its direction. During transition kite under external stimuli, positions vividly illustrate symmetry-breaking process, corresponding shift high low states. optoelectronic properties, including ferroelectricity, pyroelectricity, piezoelectricity, nonlinear optical related bulky photovoltaic effects, some them exhibit direction dependence nature. perspective employed visible approach elucidate breaking coupling transitions with eight physical in layered perovskite. We review recent research advancements outline current challenges that help us understand structure–property relationship

Язык: Английский

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Rotation of Hexamethylenetetramine Molecules Induces Reversible Electromagnetic Coupling Properties in Isothiocyanato-Nickel Complexes

International Journal of Molecular Sciences, Год журнала: 2025, Номер 26(9), С. 4050 - 4050

Опубликована: Апрель 25, 2025

Multifunctional coupled hybrid materials have extremely high potential for application in a variety of complex scenarios owing to advantages such as versatility and controllable properties. In this study, novel functional material with electromagnetic coupling properties [Ni(NCS)4(C6H13N4)2] (1) was obtained by naturally evaporating an aqueous solution nickel chloride hexahydrate, hexamethylenetetramine (HMTA), potassium thiocyanate raw materials. Structure–property characterization revealed that 1 crystallized the P21/n space group two-dimensional (2D) network structure formed hydrogen-bonding interactions between neighboring complexes. Calculations using Gaussian program indicated HMTA exhibited pronounced spatial molecular rotation. This induced obvious reversible dielectric cycling near 240 K, giving rise semiconducting optical band gap 3.35 eV. Molecular rotation caused changes 2D structure, inducing short-range magnetic ordering temperature range 2–50 K. resulted formation ferromagnet presence distinct redox peak −0.2–0.8 V range. analyses showed is supramolecular rotation-induced multifunctional crystalline

Язык: Английский

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Electrically Switchable Bipolar Polarization-Sensitive Photodetection Based on a Biaxial Ferroelectric Semiconductor

ACS Photonics, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 21, 2024

Controlling the optoelectronic properties of semiconductors by an electric field is crucial for modern electronics, information processing, computing devices, and optical communication. The electrically switchable polarization feature ferroelectrics offers potential manipulating light–matter interactions. Herein, we demonstrate bipolar polarization-sensitive photodetection in a biaxial ferroelectric semiconductor (4,4-DFPD)2PbI4 (4,4-DFPD 4,4-difluoropiperidinium). By altering direction via field, induce corresponding changes anisotropic photoresponse, which driven bulk photovoltaic effect. Based on this phenomenon, put forward encrypted communication model defined successfully implement encryption/decryption transmission process SOS signals. This work provides new insights into electrical control interactions multiaxial applications.

Язык: Английский

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Integrated Multi‐Channel Responsive Switches in a Room‐Temperature Crystal Actuator

Advanced Functional Materials, Год журнала: 2024, Номер unknown

Опубликована: Июнь 20, 2024

Abstract Integrating multiple switching behaviors in a single material is conducive to the development of smart devices, but still faces challenges, especially finding new types multiresponsive materials. Hybrid metal halides have been becoming promising candidates with potential exhibit changes various physical and chemical properties upon structural phase transitions. Herein, pair enantiomers ( R / S ‐3‐OHPD)PbI 3 (1 /1 ; 3‐HOPD = 3‐hydroxypiperidine cation) reported show multichannel around room temperature triggered by combined order‐disorder displacive type transition that arouses large lattice reorganization shape change crystals. Owing inherent chiral, noncentrosymmetric, semiconducting characteristics compounds, five other are realized besides macroscopic deformation, is, enthalpy, dielectric permittivity, photoluminescence, circularly polarized light excited photoelectric response. This study provides an exciting example crystals for integrated multifunctional

Язык: Английский

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A Melt-Processable Metal Halide Perovskite Ferroelectric

Inorganic Chemistry, Год журнала: 2024, Номер 63(43), С. 20911 - 20920

Опубликована: Окт. 17, 2024

Molecular ferroelectrics have increasingly garnered significant attention in both fundamental scientific research and technological applications due to their ease of processing, lightweight nature, mechanical flexibility. Among these, metal halide perovskite (MHP FEs), a subset molecule-based ferroelectrics, exhibit diverse functionalities owing distinctive structures, thus emerging as focal point molecular research. However, thin films, the predominant application form for MHP FEs, primarily rely on spin-coating, which presents considerable limitations. The development melt-processable FEs has been sparse, largely challenge integrating ferroelectricity with meltability. In this context, we propose rational strategy successful synthesis FE, (MBPA)

Язык: Английский

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The role of halogens in structural diversity and chirality enhancement of 1D chiral hybrid metal halides

Journal of Materials Chemistry C, Год журнала: 2024, Номер 12(27), С. 10200 - 10208

Опубликована: Янв. 1, 2024

This work establishes a model system for understanding the relationships between halogens and structural diversity as well helicity chiroptical activity.

Язык: Английский

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