Luminescence From Localized States in Solids: A First‐Principles Perspective

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: March 3, 2025

Abstract Localized‐state luminescence (LSL) has emerged as a promising mechanism for high‐performance optoelectronic applications, including lighting, photodetection, and quantum technologies. Characterized by rich intriguing spectral features, LSL involves significant electron‐phonon coupling, which varies in strength across different systems. First‐principles methods, particularly density functional theory (DFT) its extensions provide an efficient framework modeling the process with reasonable accuracy. This comprehensive review examines DFT‐based studies on three representative types of solids: from self‐trapped excitons (STEs), normal defects, intentionally doped ions. The discussion begins overview entire process, highlighting computational methods excited state structures energies, well simulations luminescent spectrum within multi‐phonon transition framework. Detailed discussions follow, focusing structural distortion modes STEs, behavior mechanisms Finally, strategies to address current challenges advance theoretical design materials are proposed, offering valuable insights future developments field.

Language: Английский

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Bridgman Method for Growing Metal Halide Single Crystals: A Review

Inorganics, Journal Year: 2025, Volume and Issue: 13(2), P. 53 - 53

Published: Feb. 11, 2025

The Bridgman method for single-crystal growth enables the formation of crystals at lower end molten material by cooling it under a precisely controlled temperature gradient. This makes particularly suitable producing high-quality materials. Over years, technique has become widely adopted growing single semiconductors, oxides, sulfides, fluorides, as well various optoelectronic, magnetic, and piezoelectric Recently, there been interest in metal halide materials, with emerging major focus both scientific community industry. However, traditional solution-based methods have several limitations, such slow rates, inconsistent crystal quality, challenges solvent selection, difficulties controlling saturation levels. These issues present significant obstacles, when large, defect-free, are needed certain high-performance As result, emerged an effective solution to overcome these challenges. review provides overview categories systems grown using recent years. classified based on their dimensionality into three-dimensional, two-dimensional, zero-dimensional structures. Furthermore, we highlight novel developed through technique. Additionally, offer brief introduction structures, properties, applications crystals, underscoring crucial role advancing research this field.

Language: Английский

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Mg(II)-Doped Perovskite-like Cs₃Cu₂I₅ Single Crystals with High Quantum Yield for Efficient X-ray Detection

Crystal Growth & Design, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 6, 2025

Cs3Cu2I5 halide perovskites doped with luminescence activators have unique optical and electronic properties; however, they tend to combine slow scintillation decay, which leads ghosting or blurriness during X-ray imaging. In this study, we produced magnesium (Mg2+)-doped single crystals (SCs) blue emission at 440 nm, the photoluminescence quantum yields ranged from 72.4 81.7%. Moreover, enhanced radioluminescence (RL) intensity light output were achieved without deteriorating decay compared those of pure SCs. Mg doping can strengthen electron–phonon coupling, (2.15 eV) a low temperature (80–290 K) showed presence additional carrier capture channels Mg-related defect levels in band gap, help reduce probability nonradiative recombination. Therefore, flexible scintillator films excellent hydrophobicity fabricated using Mg2+-doped SC powders, their spatial resolution (2.5 Lp/mm) met requirements commercial spiral computed tomography. This study found an effective strategy for enhancing self-trapped exciton metal copper-based scintillators highlighted applicability low-dose detection

Language: Английский

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Role of Pseudohalide for Enhancements of Emission Efficiency and Stability of Lead‐Free Blue‐Emitting Cs₃Cu₂I₅ Nanocrystals

Advanced Optical Materials, Journal Year: 2025, Volume and Issue: unknown

Published: March 26, 2025

Abstract Cs 3 Cu 2 I 5 has been considered a promising lead‐free perovskite material for blue light emission due to its environmental friendliness and unique optical properties. Although nanocrystals (NCs) exhibit excellent structural stability, their high specific surface area at the nanoscale inevitably leads formation of point defects caused by vacancies during self‐assembling process. In this study, structure using pseudohalide thiocyanate (SCN⁻) is modified, which an effective ionic radius similar I⁻. The strong binding energy between + ions lone electron pairs S N atoms in linear SCN⁻ enhance crystallinity NCs. addition, improve size uniformity adjusting chemical potential solvent system. incorporation also modified electronic changing bandgap improving photoluminescence quantum yield from 62.5% 76.7%. Finally, fluorescent light‐emitting diode demonstrated utilizing emission, white emitting (white‐LED) are produced combining with yellow‐emitting layer CsCu , exhibiting good operational stability.

Language: Английский

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Scintillators for Neutron Detection and Imaging: Advances and Prospects

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 31, 2024

Abstract Neutron detection and imaging play a crucial role in nuclear reaction monitoring, industrial non‐destructive testing, medicine imaging, so on. Similar to other ionizing radiation, scintillators are widely used convert neutrons into scintillation light easily read out. However, due their electrically neutral nature, the interactions of (primarily scattering or absorption with atomic nuclei) differ significantly from those high‐energy photons/charged particles. Therefore, scintillator materials must be specifically designed optimized enhance neutron capture cross sections, accounting for unique properties extreme application environment. In this review, it is begun by introducing classification neutrons, outlining sensitive elements, emphasizing key performance criteria imaging. Subsequently, reported categorized five types: metal halide, oxide, glass, liquid, organic scintillators, discussing advantages, scenarios, associated challenges. Finally, an in‐depth discussion provided on future directions field, including advancements characterization, design, fabrication processes, stability functionalization materials, expansion. It believed that review both timely essential supporting development technologies.

Language: Английский

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