Manipulating Peierls Distortion in van der Waals NbOX₂ Maximizes Second-Harmonic Generation

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(30), С. 16828 - 16834

Опубликована: Июль 19, 2023

Two-dimensional (2D) van der Waals (vdW) materials, featuring relaxed phase-matching conditions and highly tunable optical nonlinearity, endow them with potential applications in nanoscale nonlinear (NLO) devices. Despite significant progress, fundamental questions 2D NLO materials remain, such as how structural distortion affects second-order properties, which call for advanced regulation situ diagnostic tools. Here, by applying pressure to continuously tune the displacement of Nb atoms vdW NbOI2, we effectively modulate polarization achieve a 3-fold boost second-harmonic generation (SHG) at 2.5 GPa. By introducing Peierls parameter, λ, establish quantitative relationship between λ SHG intensity. Importantly, further demonstrate that enhancement can be achieved under ambient anionic substitution NbO(I1-xBrx)2 (x = 0-1) compounds, where chemical tailoring simulates effects on optimization. Consequently, NbO(I0.60Br0.40)2 0.17 exhibits giant over 2 orders magnitude higher than monolayer WSe2, reaching record-high value among reported materials. This work unambiguously demonstrates correlation property and, more broadly, opens new paths development manipulating structure distortions.

Язык: Английский

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Exciton engineering of 2D Ruddlesden–Popper perovskites by synergistically tuning the intra and interlayer structures

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Апрель 8, 2024

Abstract Designing two-dimensional halide perovskites for high-performance optoelectronic applications requires deep understanding of the structure-property relationship that governs their excitonic behaviors. However, a design framework considers both intra and interlayer structures modified by A-site spacer cations, respectively, has not been developed. Here, we use pressure to synergistically tune uncover structural modulations result in improved performance. Under applied pressure, (BA) 2 (GA)Pb I 7 exhibits 72-fold boost photoluminescence 10-fold increase photoconductivity. Based on observed change, introduce descriptor χ describes characteristics establish general quantitative between quantum yield: smaller correlates with minimized trapped excitons more efficient emission from free excitons. Building this principle, perovskite (CMA) (FA)Pb small an impressive yield 59.3%.

Язык: Английский

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Emerging Two-Dimensional Organic Semiconductor-Incorporated Perovskites─A Fascinating Family of Hybrid Electronic Materials

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(38), С. 20694 - 20715

Опубликована: Сен. 14, 2023

Halide perovskites have attracted a great amount of attention owing to their unique materials chemistry, excellent electronic properties, and low-cost manufacturing. Two-dimensional (2D) halide perovskites, originating from three-dimensional (3D) perovskite structures, are structurally more diverse therefore create functional possibilities beyond 3D perovskites. The much less restrictive size constraints on the organic component these hybrid particularly provide an exciting platform for designing unprecedented functionalities at molecular level. In this Perspective, we discuss concept recent development sub-class 2D namely, semiconductor-incorporated (OSiPs). OSiPs combine functionality semiconductors with soft dynamic lattice, offering opportunities tailoring energy landscape, lattice carrier dynamics, electron/ion transport properties various fundamental studies, as well device applications. Specifically, summarize advances in design, synthesis, structural analysis conjugated moieties application photovoltaics, light-emitting devices, transistors. Lastly, challenges further integration novel functionality, film quality, stability issues addressed.

Язык: Английский

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Pressure-Modulated Anomalous Organic–Inorganic Interactions Enhance Structural Distortion and Second-Harmonic Generation in MHyPbBr₃ Perovskite

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(43), С. 23842 - 23848

Опубликована: Окт. 20, 2023

Organic-inorganic halide perovskites possess unique electronic configurations and high structural tunability, rendering them promising for photovoltaic optoelectronic applications. Despite significant progress in optimizing the characteristics of organic cations inorganic framework, role organic-inorganic interactions determining optical properties has long been underappreciated remains unclear. Here, by employing pressure tuning, we realize continuous regulation a lead perovskite, MHyPbBr3 (MHy+ = methylhydrazinium, CH3NH2NH2+). Compression enhances strengthening Pb-N coordinate bonding N-H···Br hydrogen bonding, which results higher distortion framework. Consequently, second-harmonic-generation (SHG) intensity experiences an 18-fold increase at 1.5 GPa, order-disorder phase transition temperature increases from 408 K under ambient to 454 industrially achievable level 0.5 GPa. Further compression triggers sudden non-centrosymmetric centrosymmetric transition, accompanied anomalous bandgap 0.44 eV, stands as largest boost all known perovskites. Our findings shed light on intricate correlations among interactions, octahedral distortion, SHG and, more broadly, provide valuable insights into design property optimization through cation engineering

Язык: Английский

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Anomalous Charge Transfer from Organic Ligands to Metal Halides in Zero‐Dimensional [(C₆H₅)₄P]₂SbCl₅ Enabled by Pressure‐Induced Lone Pair‐π Interaction

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(37)

Опубликована: Июль 19, 2023

Low-dimensional (low-D) organic metal halide hybrids (OMHHs) have emerged as fascinating candidates for optoelectronics due to their integrated properties from both and inorganic components. However, most of low-D OMHHs, especially the zero-D (0D) compounds, inferior electronic coupling between ligands halides prevents efficient charge transfer at hybrid interfaces thus limits further tunability optical properties. Here, using pressure regulate interfacial interactions, is achieved, which leads a near-unity photoluminescence quantum yield (PLQY) around 6.0 GPa in 0D OMHH, [(C6 H5 )4 P]2 SbCl5 . In situ experimental characterizations theoretical simulations reveal that pressure-induced lone-pair electrons Sb3+ π benzene ring (lp-π interaction) serves an unexpected "bridge" transfer. Our work opens versatile strategy new materials design by manipulating lp-π interactions organic-inorganic systems.

Язык: Английский

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Steric hindrance effects on the retention of pressure-induced emission toward scintillators

Cell Reports Physical Science, Год журнала: 2023, Номер 4(6), С. 101445 - 101445

Опубликована: Май 31, 2023

The success in pressure-induced emission (PIE) from hybrid perovskites greatly facilitates the potential development of high-efficiency white-light-emitting diodes and scintillators. However, its reversibility essentially inhibits practical applications. Furthermore, urgent demand for scintillators requests fast decay response time a large Stokes shift that suppresses self-adsorption. Here, we report quantitative steric hindrance effect different organic components perovskites. Moreover, 1-(2-naphthyl)methanamine (NAPH)+ with complex configuration is further introduced to experimentally prepare 2D perovskite (NAPH)2PbCl4 nanoplates. Notably, benefiting increased barrier phase transition associated high index (SEI) 5.98, harvested amorphous exhibits twice more intensity than initial emission, shortened 1.73 ns, an enlarged 260.7 nm. This study establishes correlation between PIE retention hindrance, improving material design synthesis applications

Язык: Английский

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Two-dimensional lead halide perovskite lateral homojunctions enabled by phase pinning

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Апрель 11, 2024

Two-dimensional organic-inorganic hybrid halide perovskites possess diverse structural polymorphs with versatile physical properties, which can be controlled by order-disorder transition of the spacer cation, making them attractive for constructing semiconductor homojunctions. Here, we demonstrate a space-cation-dopant-induced phase stabilization approach to creating lateral homojunction composed ordered and disordered phases within two-dimensional perovskite. By doping small quantity pentylammonium into (butylammonium)

Язык: Английский

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Quantifying Structural Polarization by Continuous Regulation of Lone-Pair Electron Expression in Molecular Crystals

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(32), С. 22469 - 22475

Опубликована: Авг. 1, 2024

Rational design of structural polarization is vital for modern technologies, as it allows the physical properties functional materials to be tailored. An effective approach governing involves utilization stereochemical lone-pair electrons (LPEs). However, despite recognized significance LPEs in controlling polarization, there remains a lack understanding regarding quantitative relationship between their expression and extent polarization. Here, by using pressure continuously tune LPE expression, we achieve precise control quantification which brings enhanced second harmonic generation (SHG) molecular crystal SbI

Язык: Английский

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Pressure-controlled free exciton and self-trapped exciton emission in quasi-one-dimensional hybrid lead bromides

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Авг. 27, 2024

Hybrid metal halides represent a novel type of semiconductor light emitters with intriguing excitonic emission properties, including free exciton and self-trapped emission. Achieving precise control over these two emissions in hybrid is highly desired yet remains challenging. Here, the complete transformation from intrinsically broadband to distinctively sharp quasi-one-dimensional halide (C2H10N2)8[Pb4Br18]·6Br ribbon width n = 4, successfully achieved based on high-pressure method. During compression, pressure-induced phonon hardening continuously reduces exciton–phonon coupling, therefore suppressing localization quenching original Notably, further compression triggers delocalization induce intense emission, accompanied reduced carrier effective masses improved charge distribution. Controlled investigations indicate that > 2 necessary realize generate similar halides. This work presents an important photophysical process transitions without chemical regulation, promoting rational synthesis emissions. show or broad excitons depending structural dimensionality. authors both types through pressure regulation quasi−1D samples.

Язык: Английский

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Structurally Flexible 2D Spacer for Suppressing the Electron–Phonon Coupling Induced Non-Radiative Decay in Perovskite Solar Cells

Nano-Micro Letters, Год журнала: 2024, Номер 16(1)

Опубликована: Апрель 24, 2024

This study presents experimental evidence of the dependence non-radiative recombination processes on electron-phonon coupling perovskite in solar cells (PSCs). Via A-site cation engineering, a weaker has been achieved by introducing structurally soft cyclohexane methylamine (CMA

Язык: Английский

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