Porphyrin-Based Covalent Organic Frameworks Anchoring Au Single Atoms for Photocatalytic Nitrogen Fixation

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(11), С. 6057 - 6066

Опубликована: Март 8, 2023

The development of efficient photocatalysts for N2 fixation to produce NH3 under ambient conditions remains a great challenge. Since covalent organic frameworks (COFs) possess predesignable chemical structures, good crystallinity, and high porosity, it is highly significant explore their potential photocatalytic nitrogen conversion. Herein, we report series isostructural porphyrin-based COFs loaded with Au single atoms (COFX-Au, X = 1-5) fixation. porphyrin building blocks act as the docking sites immobilize well light-harvesting antennae. microenvironment catalytic center precisely tuned by controlling functional groups at proximal distal positions units. As result, COF1-Au decorated strong electron-withdrawing exhibits activity toward production rates 333.0 ± 22.4 μmol g-1 h-1 37.0 2.5 mmol gAu-1 h-1, which are 2.8- 171-fold higher than that COF4-Au electron-donating porphyrin-Au molecular catalyst, respectively. could be further increased 427.9 18.7 61.1 2.7 catalysis COF5-Au featuring two different kinds groups. structure-activity relationship analysis reveals introduction facilitates separation transportation photogenerated electrons within entire framework. This work manifests structures optoelectronic properties COF-based can finely through rational predesign level, thus leading superior evolution.

Язык: Английский

---

Pressure‐Induced Emission toward Harvesting Cold White Light from Warm White Light

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(18), С. 10082 - 10088

Опубликована: Март 24, 2021

Abstract The pressure‐induced emission (PIE) behavior of halide perovskites has attracted widespread attention and potential application in pressure sensing. However, high‐pressure reversibility largely inhibits practical applications. Here, we describe the enhancement non‐doping control color temperature two‐dimensional perovskite (C 6 H 5 CH 2 NH 3 ) PbCl 4 ((PEA) nanocrystals (NCs) through processing. A remarkable times PIE was achieved at a mild 0.4 GPa, which highly associated with enhanced radiative recombination self‐trapped excitons. Of particular importance is retention 1.6 dense (PEA) NCs upon complete release pressure, accompanied by change from “warm” (4403 K) to “cold” white light 14295 K. irreversible structural amorphization, facilitates remaining local distortion inorganic Pb‐Cl octahedra respect steric hindrance organic PEA + cations, should be greatly responsible for quenched high‐efficiency photoluminescence.

Язык: Английский

---

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

---

Pressure-Driven Reverse Intersystem Crossing: New Path toward Bright Deep-Blue Emission of Lead-Free Halide Double Perovskites

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(37), С. 15176 - 15184

Опубликована: Сен. 10, 2021

Maximizing the regeneration of singlet excitons remains a considerable challenge in deep-blue emission systems to obtain low-cost, high-efficiency fluorescent materials. However, formation long-lifetime triplet generally dominates radiative process, making it greatly difficult harvest with high color purity because depression excitons. Here, very bright double perovskite Cs2Na0.4Ag0.6InCl6 alloyed Bi doping (CNAICB) was successfully achieved by pressure-driven reverse intersystem crossing (RISC), an abnormal photophysical process energy transfer from excited state back singlet. Therein, inherently broad CNAICB associated self-trapped (STEs) at states, whereas recombination STEs populated states responsible for observed emission. Moreover, corresponds Commission Internationale de L'Eclairage (CIE) coordinates (0.16, 0.06) 5.01 GPa, which meets requirement Rec. 2020 display standards. Likewise, pressure introduced as efficient tool rule out possibility free and clarify long-standing conventional dispute over origin low-wavelength Cs2AgInCl6. Our study not only demonstrates that can be robust means boost but also provides deep insights into structure-property relationship lead-free perovskites.

Язык: Английский

---

Enhanced Photoluminescence and Photoresponsiveness of Eu³⁺ Ions‐Doped CsPbCl₃ Perovskite Quantum Dots under High Pressure

Advanced Functional Materials, Год журнала: 2021, Номер 31(31)

Опубликована: Май 27, 2021

Abstract Metal halide perovskite quantum dots (QDs) have garnered tremendous attention in optoelectronic devices owing to their excellent optical and electrical properties. However, these QDs are plagued by pressure‐induced photoluminescence (PL) quenching, which greatly restricts potential applications. Herein, the unique properties of Eu 3+ ‐doped CsPbCl 3 under high pressure reported. Intriguingly, PL ions displays an enhancement with up 10.1 GPa still preserves a relatively intensity at 22 GPa. The structural analysis indicates that sample experiences isostructural phase transition approximately 1.53 GPa, followed amorphous state evolution, is simulated confirmed through density functional theory calculations. can be associated enhanced energy transfer rate from excitonic ions. photoelectric performance compression preserved upon release pressure, attributed decreased defect increased carrier mobility induced pressure. This work enriches understanding high‐pressure behavior rare‐earth‐doped luminescent materials proves technique promising way design realize superior materials.

Язык: Английский

---

Reconfiguring band-edge states and charge distribution of organic semiconductor–incorporated 2D perovskites via pressure gating

Science Advances, Год журнала: 2022, Номер 8(44)

Опубликована: Ноя. 2, 2022

Two-dimensional (2D) semiconductor heterostructures are key building blocks for many electronic and optoelectronic devices. Reconfiguring the band-edge states modulating their interplay with charge carriers at interface in a continuous manner have long been sought yet challenging. Here, using organic semiconductor-incorporated 2D halide perovskites as model system, we realize manipulation of distribution via mechanical-rather than chemical or thermal-regulation. Compression induces band-alignment switching redistribution due to different pressure responses inorganic blocks, giving controllable emission properties perovskites. We propose demonstrate "pressure gating" strategy that enables control multiple within single material. also reveal transition organic-inorganic is intrinsically not well resolved room temperature owing thermally activated transfer shuffling carriers. This work provides important fundamental insights into energetics carrier dynamics hybrid heterostructures.

Язык: Английский

---

Chirality-Dependent Structural Transformation in Chiral 2D Perovskites under High Pressure

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(16), С. 8908 - 8916

Опубликована: Апрель 14, 2023

Chiral perovskites have attracted considerable attention owing to their potential applications in spintronic- and polarization-based optoelectronic devices. However, the structural chirality/asymmetry transfer mechanism between chiral organic ammoniums achiral inorganic frameworks is still equivocal, especially under extreme conditions, as systematic differences been rarely explored. Herein, we successfully synthesized a pair of new enantiomeric perovskite (S/R-3PYEA)PbI4 (3PYEA2+ = C5NH5C2H4NH32+) an (rac-3PYEA)PbI4. Hydrostatic pressure was used, for first time, systematically investigate evolution optical behavior At approximately 7.0 GPa, exhibits chirality-dependent transformation with bandgap "red jump" dramatic piezochromism from translucent red opaque black. Upon further compression, previously unreported chirality-induced negative linear compressibility (NLC) achieved (S/R-3PYEA)PbI4. High-pressure characterizations first-principles calculations demonstrate that pressure-driven homodirectional tilting homochiral ammonium cations strengthens interactions S/R-3PYEA2+ Pb–I frameworks, inducing formation asymmetric hydrogen bonds N–H···I–Pb The enhanced H-bonding break symmetry trigger greater degree in-plane out-of-plane distortion [PbI6]4– octahedra, which are responsible phase transition NLC, respectively. Nevertheless, balanced H-bonds incurred by equal proportions S-3PYEA2+ R-3PYEA2+ counteract force, leading absence transition, spectral jump", NLC

Язык: Английский

---

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

---

Pressure tailoring electron-phonon coupling toward enhanced yellow photoluminescence quantum yield and piezochromism

Cell Reports Physical Science, Год журнала: 2023, Номер 4(11), С. 101663 - 101663

Опубликована: Окт. 30, 2023

Improvements in yellow light production, a healthy source for the eyes that is also beneficial to biological growth, are needed satisfy practical requirements of solid-state lighting. Here, we report high-brightness emission zero-dimensional lead-free double-perovskite Rb2TeCl6 microcrystals (MCs) driven by high-pressure processing. We note photoluminescence quantum yields (PLQYs) experience significant enhancement an order magnitude upon mild pressure 1.7 GPa. The overlap between ground state and self-trapped reduced pressure-tailored electron-phonon coupling. Accordingly, phonon-assisted non-radiative relaxation inhibited, resulting considerable increase PLQY. Furthermore, marked piezochromism from pale green realized compressed MCs. Our study not only enables as robust tool boost efficiency but provides deep insights into underlying photophysical mechanism, facilitating rational synthesis materials design.

Язык: Английский

---

Band gap engineering and optoelectronic properties of all-inorganic Ruddlesden-Popper halide perovskites Cs2B(X1-uYu)4 (B = Pb, Sn; X/Y = Cl, Br, I)

Materials Science in Semiconductor Processing, Год журнала: 2023, Номер 157, С. 107308 - 107308

Опубликована: Янв. 9, 2023

Язык: Английский

---