Optoelectronic insights of lead-free layered halide perovskites

Chemical Science, Год журнала: 2024, Номер 15(20), С. 7374 - 7393

Опубликована: Янв. 1, 2024

Two-dimensional organic-inorganic halide perovskites have emerged as promising candidates for a multitude of optoelectronic technologies, owing to their versatile structure and electronic properties. The optical properties are harmoniously integrated with both the inorganic metal octahedral slab, organic spacer layer. layers can also assemble into periodically stacked nanoplatelets, which interconnected by ammonium cation, resulting in formation superlattice or superstructure. In this perspective, we explore structural, electronic, lead-free hybrid halides, layered perovskite single crystals nanostructures, expanding our understanding diverse applications enabled these structures. superlattices function layer thickness, center either divalent combination monovalent trivalent cations, composition. distinct absorption emission features guided structural deformation, electron-phonon coupling, polaronic effect. Among possibilities, focused on photodetection capability crystals, elucidated descriptors such excitonic band gap, effective mass, carrier mobility, Rashba splitting, spin texture that decides direct component transitions.

Язык: Английский

---

Sequential addition of cations increases photoluminescence quantum yield of metal nanoclusters near unity

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Янв. 11, 2025

Abstract Photoluminescence is one of the most intriguing properties metal nanoclusters derived from their molecular-like electronic structure, however, achieving high photoluminescence quantum yield (PLQY) core-dictated fluorescence remains a formidable challenge. Here, we report efficient suppression total structural vibrations and rotations, management pathways rates electron transfer dynamics to boost near-unity absolute PLQY, by decorating progressive addition cations. Specifically, with sequential Zn 2+ , Ag + Tb 3+ into 3-mercaptopropionic acids capped Au (NCs), low-frequency vibration core progressively decreases 144.0, 55.2 40.0 cm −1 coupling strength electrons-high-frequency related surface motifs gradually diminishes 40.2, 30.5 14.4 meV. Moreover, introducing cation additives significantly reduces time 40, 27 12 ps in pathway staple core. This benefits shrinkage structure that speeds up shell-core transition, particular, provides hopping platform for excited electrons as intrinsic ladder-like energy level structure. As result, it allows remarkable enhancement 51.2%, 83.4%, 99.5%.

Язык: Английский

---

Controlling Triplet-Harvesting Pathways and Nonlinear Optical Properties in Cu(I) Iodide-Based Polymers through Ligand Engineering

The Journal of Physical Chemistry Letters, Год журнала: 2025, Номер unknown, С. 1549 - 1558

Опубликована: Фев. 4, 2025

Organic-inorganic hybrid metal halides have become enormously important in optoelectronics, sensing, photosensitization, etc. In this study, we report a structural transition from staircase configuration to cubane Cu(I) iodide-based polymers influenced by the coordination behavior of two different π*-acceptor ligands. The polymer structure, coordinated with 3-cyanopyridine, demonstrates efficient thermally activated delayed fluorescence (metal+halide)-to-ligand charge transfer [1/3(M+X)LCT] states, singlet-triplet energy splitting ∼9 meV. Conversely, upon replacement cyano an amino group at same position, one-dimensional polymeric structure Cu4I4 cubane-type clusters is formed, which shows strong cluster-centered (3CC) orange emission room temperature. Temperature-dependent photoluminescence studies indicate that 3CC state behaves as self-trapped excitonic significant exciton-phonon coupling having Huang-Rhys factor 58.6. Additionally, cluster acts nonlinear optical material showing third harmonic generation χ(3) value 1.32 × 10-18 m2 V-2 and laser-induced damage threshold 25.87 GW/cm2.

Язык: Английский

---

Lead-free cesium europium bromide perovskite nanocrystals in glass for white light-emitting diode and X-ray imaging

Chemical Engineering Journal, Год журнала: 2025, Номер unknown, С. 160795 - 160795

Опубликована: Фев. 1, 2025

Язык: Английский

---

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

Advanced Functional Materials, Год журнала: 2025, Номер unknown

Опубликована: Март 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.

Язык: Английский

---

B(I)‐Site Alkali Metal Engineering of Lead‐Free Perovskite Nanocrystals for Efficient X‐Ray Detection and Imaging

Advanced Optical Materials, Год журнала: 2024, Номер 12(12)

Опубликована: Янв. 17, 2024

Abstract Lead‐free metal halide double perovskites have emerged as promising scintillators owing to their superior optoelectronic properties, low‐cost and solution processability. However, it is still challenging develop high‐performance flexible X‐ray based on the B(I)‐site alkali modulation in lead‐free perovskite nanocrystals (NCs). Herein, a series of novel Cs 2 B(I)GdCl 6 (B: Li, Na, K) A B(I)M(III)X NCs structures are successfully synthesized, optical scintillator properties which significantly sensitive metals with doping Sb 3+ . They showed efficient self‐trapped exciton (STE) emission high photoluminescence quantum yield (PLQY) exhibited highest detection limit (86 nGy air s −1 ) excellent spatial resolutions (>15 lp mm ). The femtosecond transient absorption measurement theoretical analysis further revealed that fundamentally balanced exciton–phonon coupling appropriate STEs formation energy barrier electron localization thus improved properties. This engineering offers strategy bright luminescent for imaging devices.

Язык: Английский

---

Ultraviolet photoluminescent materials from traditional ion-activated phosphors to emerging carbon dots and perovskites

Materials Science and Engineering R Reports, Год журнала: 2024, Номер 159, С. 100803 - 100803

Опубликована: Май 10, 2024

Язык: Английский

---

Zero-Dimensional Copper(I) Halide Microcrystals as Highly Efficient Scintillators for Flexible X-ray Imaging

ACS Applied Materials & Interfaces, Год журнала: 2024, Номер 16(31), С. 41165 - 41175

Опубликована: Июль 25, 2024

Commercially available rare-earth-doped inorganic oxide materials have been widely applied as X-ray scintillators, but the fragile characteristics, high detection limit, and harsh preparation condition seriously restrict their wide applications. Furthermore, it remains a huge challenge to realize flexible imaging technology for real-time monitoring of curving interface complex devices. To address these issues, we herein report two isostructural cuprous halides zero-dimensional (0D) [AEPipz]CuX3·X·H2O (AEPipz = N-aminoethylpiperazine, X Br I) with controllable size nanosize crystal highly efficient scintillators toward imaging. These exhibit cyan photoluminescence radioluminescence emissions highest quantum yield 92.1% light 62,400 photons MeV–1, respectively, surpassing most commercially scintillators. Meanwhile, ultralow limit 95.7 nGyair s–1 was far below dose required diagnosis (5.5 μGyair s–1). More significantly, film is facilely assembled excellent foldability crack resistance, which further acts scintillation screen achieving spatial resolution 17.4 lp mm–1 in imaging, demonstrating potential application wearable radiation radiography. The combined advantages yield, low flexibility promote 0D promising

Язык: Английский

---

Breakthrough Boost of Stokes Fluorescence from Er³⁺ in Perovskites for Flexible Temperature Sensing

Laser & Photonics Review, Год журнала: 2024, Номер 18(10)

Опубликована: Апрель 9, 2024

Abstract Perovskites with ultra‐low phonon energy have excellent radiation properties, while the population distribution of its luminescent initial state needs to be facilitated further optimize stokes fluorescence Er 3+ under high‐energy photons excitation. Herein, UV excitability is remodeled by building an transfer channel from Sb in Cs 2 NaInCl 6 (CNIC) microcrystal realize enhancement . Under excitation, breakthrough boost observed :Sb ‐Er (CNIC:Sb‐Er), and sensitization coefficient CNIC derived as high 112. Moreover, CNIC:Sb‐Er embedded into functional fibers enhance crystal stability composite flexibility, which form strong transition probability. Finally, a high‐precision temperature sensing achieved based on FIR (fluorescence intensity ratios) technology, maximum relative sensitivities phosphors CNIC:Sb‐Er/PAN reach 1.13 1.10% K −1 , respectively, indicating that potential applications optical sensors.

Язык: Английский

---

Cation‐Doped Cs₂B^IB^IIIX₆ Double Perovskites: Electronic Structures, Optical Properties, and Optoelectronic Applications

Advanced Optical Materials, Год журнала: 2024, Номер 12(30)

Опубликована: Авг. 13, 2024

Abstract Recently, all‐inorganic halide double perovskites (DPs) with a chemical formula of Cs 2 B I III X 6 have been emerging as shinning star to be used in modern optoelectronic devices, due their unique advantages such environmentally friendly, high absorption coefficient, low trap densities, tunable bandgap, variable constituent elements and valences states through or sites engineering. In this review, first, the impact cation doping on electronic structure optical properties DPs are systematically overviewed, which cover several key issues including interconversion between direct indirect band gaps, enhancement light absorption, promotion exciton localization, elucidation energy transfer mechanisms, regulation defect density improvement both stability luminescence efficiency. Subsequently, state‐of‐the‐art research activities regarding interesting device applications discussed, light‐emitting diodes, anticounterfeiting encryption, X‐ray scintillators, thermometry. Finally, existing difficulties, prospects, directions field proposed.

Язык: Английский

---