Hafnium-Based Chiral 2D Organic–Inorganic Hybrid Metal Halides: Engineering Polarity and Nonlinear Optical Properties via Para-Substituent Effects

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 8, 2025

Two-dimensional (2D) organic–inorganic hybrid metal halides (OIMHs), characterized by noncentrosymmetric structures arising from the incorporation of chiral organic molecules that break inversion symmetry, have attracted significant attention. Particularly, chiral-polar 2D OIMHs offer a unique platform for multifunctional applications, as coexistence chirality and polarity enables simultaneous manifestation distinct properties such nonlinear optical (NLO) effects, circular dichroism (CD), ferroelectricity. In this study, we report first synthesis hafnium (Hf)-based OIMHs, achieved through strategic para-substituents on benzene ring components. By tuning substituents, successfully modulate crystal structures, resulting in both chiral-nonpolar systems. Our analysis structural properties, supported density functional theory calculations, demonstrates these materials can be systematically tuned, enabling adjustable band gaps CD UV range (200–280 nm). Notably, halogen substitution at para-position layer produces tunable ranging 4.33 to 4.48 eV, widest reported date OIMHs. Furthermore, exhibit enhanced NLO including remarkable 3.3-fold increase second-harmonic generation intensity compounds compared their counterparts. These findings position Hf-based promising candidates UV-region devices self-driven circularly polarized light detectors, offering new opportunities designing optoelectronic harnessing interplay between polarity.

Language: Английский

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2D Multilayered Perovskite Ferroelectric with Halogen Bond Induced Interlayer Locking Structure toward Efficient Self‐Powered X‐Ray Detection

Small, Journal Year: 2025, Volume and Issue: unknown

Published: March 24, 2025

Abstract 2D Ruddlesden‐Popper (RP) hybrid perovskite ferroelectrics have emerged as a promising class of direct X‐ray detection materials. However, their intrinsic van der Waals gaps result in weak interlayer interactions that destabilize the layered motifs impacting stability detector. Thus, it is crucial but remains toughly challenge to enhance exploring stable RP ferroelectric detectors. Here, halogen bond proposed obtaining trilayered ferroelectric, (BrPA) 2 (EA) Pb 3 Br 10 ( BEPB , BrPA = 3‐bromopropylaminium; EA ethylammonium). Strikingly, strong Br···Br bonds lock cations inorganic skeletons, and C─H···Br hydrogen bridge adjacent spacing sheets, which effectively improves structural suppresses ion migration. The typical P‐E hysteresis loops reveal its concrete behaviors, giving large polarization ≈7.3 µC cm −2 . Consequently, ‐based detector results high sensitivity 562.6 Gy −1 at 0 V bias, most importantly, exhibits low baseline drift exceptional environmental stability. As far known, strengthening multilayered achieve efficient unprecedented, sheds light on future design optoelectronic devices toward practical applications.

Language: Английский

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Stable Self-powered X-ray Detection with Low Detection Limit By a Green Halide Hybrid Perovskite Ferroelectric Crystal

Chemical Science, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

The remarkable FE-PV effect driven stable and self-powered X-ray detection in a green halide hybrid ferroelectric crystal [H 2 mdap]BiBr 5 with relatively high sensitivity, low limit, good stability, advancing towards safer more detection.

Language: Английский

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Multiple Interactions in Polar Lead‐Free Perovskites toward Highly Stable X‐Ray Detection

Advanced Science, Journal Year: 2025, Volume and Issue: unknown

Published: April 3, 2025

Lead-free halide perovskites have emerged as a promising class of high-performance "green" X-ray detecting semiconductors due to their nontoxicity and strong absorption. However, ion migration caused by high operating electric field remains bottleneck limiting the long-term stability perovskite detectors. Herein, introducing multiple halogen interactions in lead-free perovskites, stable detection is successfully realized. Specifically, 0D polar bismuth (R/S-BPEA)4Bi2I10 (1R/1S, R/S-BPEA = R/S-1-(4-bromophenyl)ethylammonium) are designed Br-substituted chiral organic cation BPEA, which exists with molecular electrostatic forces between Br atom neighboring benzene ring interaction Br···I. Notably, introduction improves activation energy migration, makes dark current drift detector low 3.25 × 10-8 nA cm-1 s-1 V-1 at 2500 V cm-1. Furthermore, excellent operational under prolonged irradiation unchanged device sensitivity after 90 days exposure air, further demonstrates improved perovskites. Meanwhile, chiral-polar characteristic 1R/1S gives them potential for self-powered detection, limit 183 nGy zero bias single-crystal devices. This study opens new avenues future development "green", highly stable, radiation

Language: Английский

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Bromine‐Substituted Cation Anchoring to Suppress Ion Migration in Alternating Cations Intercalation‐Type Perovskite for Stable X‐Ray Detection

Small Structures, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 17, 2024

Metal halide perovskites have emerged as excellent direct X‐ray detection materials owing to their large mobility‐lifetime product, strong radiation absorption, and low‐cost preparation. However, it is still a challenge achieve stable due the limitations associated with severe ion migration under high voltage bias. Herein, based on bromine substitution strategy suppress migration, 2D alternating cations intercalation‐type (ACI) perovskite, ( R ‐MPA)(BrEA)PbBr 4 1 , ‐MPA = methylphenethylamm‐onium; BrEA 2‐bromoethylamine) reported detection. Specifically, introducing Br atom forms additional intermolecular interactions (i.e., Br···π) enhances hydrogen bonding interactions, greatly improving structure stability. Based this enhanced interaction, presents higher activation energy of (1.05 eV) than that ‐MPA)EAPbBr resulting in lower dark current drift 9.17 × 10 −8 nA cm −1 s V revealing suppression migration. Consequently, ‐based detector shows sensitivity 2653.7 μC Gy −2 and, most importantly, outstanding operational environmental stability, maintaining ≈91% its initial at 50 bias after 90 days air. This work demonstrates an efficient for halogen via ACI

Language: Английский

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