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The synthesis, structure, and phosphorescence properties of twofamilies of triphosphine-supported Au(I)–Ag(I) heteronuclearalkynyl cluster complexes with unprecedented Au2Ag2and Au8Ag4cluster structures are described.The phosphorescence emission over the whole visible light region wassystematically tuned through modification of the electronic effectsin aromatic acetylide ligands to attain bright phosphorescence withdifferent luminescent colors. Introduction of electron-withdrawingCF3to phenylacetylides results in the emission spectralblue-shift, while it shows progressive red-shift upon introducingelectron-donating But, OMe, or NMe2. As demonstratedfrom both experimental and theoretical studies, the phosphorescencearises primarily from 3LLCT/3IL and Au2Ag2/Au8Ag4cluster-centered 3[d→p] transitions. [ABSTRACT FROM AUTHOR]

A series of highly phosphorescent PtAg2 heterotrinu-clear alkynyl complexes with bis(diphenylphosphinomethyl)-phenylphosphine (dpmp) were prepared and characterized structurally. The solution phosphorescence with various emitting colors is systematically modulated by modifying substituents as well as n-conjugated systems in aromatic acetylides. The crystals, powders, or films exhibit reversible stimuli-responsive phosphorescence changes upon exposure to vapor of MeCN, pyridine, DMF, etc., resulting from perturbation of d8-d10 metallophilic interaction in the excited states as a consequence of the formation/disruption of Ag--solvent bonds. Both experimental and time-dependent density functional theory (TD-DFT) studies demonstrate that d8-d10 metallophilic interaction exerts a crucial role on phosphorescent characteristics due to the PtAg2 cluster-based ³[d → p] state. This study affords a paradigm for phosphorescence modulation in d8--d10 heteronuclear complexes. [ABSTRACT FROM AUTHOR]

Chiral 3D perovskites pose challenges compared to lower-dimensional variants due to limited chiral organic cation options. Here, we present a universal and controlled method for synthesizing chiral 3D lead halide perovskites using organic amines or alcohols as chiral templates. Introducing these templates to PbCl 2 in N , N -dimethylformamide (DMF) under acidic conditions induces the crystallization of R/S [DMA]PbCl 3 (DMA = dimethylamine). The resulting structure aligns with the templates used, stemming from the helical Pb 2 Cl 9 5- chain as verified by single-crystal X-ray diffraction. Furthermore, the chiral perovskite exhibits absorption and circular dichroism (CD) signals in the high-energy band, enabling the circularly polarized light (CPL) detection in the UV spectrum. A CPL detector constructed by this chiral perovskite demonstrates excellent performance, boasting an anisotropy factor for photocurrent ( g Iph ) of 0.296. Our work not only introduces a novel and controllable method for crafting chiral perovskites but also opens new avenues for circularly polarized light detection.

Photoactive metal ions doping is an efficient way to modulate the photophysical properties of perovskite. Herein, we report a zero-dimensional (0D) InCl 6 (C 4 H 10 SN) 4 ·Cl:Sb 3+ by doping Sb 3+ into InCl 6 (C 4 H 10 SN) 4 ·Cl , which undergoes a significant enhancement of the emission peak at 550 nm with photoluminescence quantum yield boosting from 20% to 90%. Interestingly, a red-shifted emission is observed on InCl 6 (C 4 H 10 SN) 4 ·Cl:Sb 3+ upon exposure to ethanol and DMF vapor with the emission peak red-shifted from 550 to 580 and 600 nm, respectively. Furthermore, the transformation is reversed after drying the vapor-exposed InCl 6 (C 4 H 10 SN) 4 ·Cl:Sb 3+ at ambient conditions. Detailed characterizations reveal that the crystal packing and structure distortion account for the reversible luminescent vapochromism. Thanks to the superior stability and feasible transformation of InCl 6 (C 4 H 10 SN) 4 ·Cl:Sb 3+ at ambient conditions, a DMF sensor was fabricated by coating the mixture of InCl 6 (C 4 H 10 SN) 4 ·Cl:Sb 3+ and PMMA into patterned substrate, which exhibits an obvious luminescent change upon release and uptake of DMF and excellent stability and producibility in several cycles.

Highly soluble d 8 -d 10 heteronuclear phosphors afford an alternative approach to achieve high-efficiency organic light-emitting diodes (OLEDs) through a solution process. In this work, four highly phosphorescent d 8 -d 10 heteronuclear complexes with significant Pt-Au interactions were prepared. By judicious selection of sterically hindered and π-conjugated substituents in triphosphine ligands, the phosphorescence is dramatically promoted through effectively prohibiting nonradiative thermal relaxation with an efficiency of 0.94-0.99 in doping films. Exploiting highly emissive Pt-Au complexes as phosphorescent dopants, ultrahigh-efficiency solution-processed OLEDs were attained. The peak current efficiency, power efficiency, and external quantum efficiency are 96.2 cd A -1 , 65.0 lm W -1 , and 26.4% for the green-emitting PtAu 2 phosphor and 68.6 cd A -1 , 42.5 lm W -1 , and 25.1% for the orange-emitting Pt 2 Au phosphor, which represent the state-of-art for solution-processed OLEDs based on non-iridium phosphors.

Scintillators, which are capable of converting ionizing radiation into visible photons, are an integral part of medical, security, and commercial diagnostic technologies such as X-ray imaging, nuclear cameras, and computed tomography. Conventional scintillator fabrication typically involves high-temperature sintering, generating agglomerated powders or large bulk crystals, which pose major challenges for device integration and processability. On the other hand, colloidal quantum dot scintillators cannot be cast into compact solid films with the necessary thickness required for most X-ray applications. Here, we report the room-temperature synthesis of a colloidal scintillator comprising CsPbBr 3 nanosheets of large concentration (up to 150 mg/mL). The CsPbBr 3 colloid exhibits a light yield (∼21000 photons/MeV) higher than that of the commercially available Ce:LuAG single-crystal scintillator (∼18000 photons/MeV). Scintillators based on these nanosheets display both strong radioluminescence (RL) and long-term stability under X-ray illumination. Importantly, the colloidal scintillator can be readily cast into a uniform crack-free large-area film (8.5 × 8.5 cm 2 in area) with the requisite thickness for high-resolution X-ray imaging applications. We showcase prototype applications of these high-quality scintillating films as X-ray imaging screens for a cellphone panel and a standard central processing unit chip. Our radiography prototype combines large-area processability with high resolution and a strong penetration ability to sheath materials, such as resin and silicon. We reveal an energy transfer process inside those stacked nanosheet solids that is responsible for their superb scintillation performance. Our findings demonstrate a large-area solution-processed scintillator of stable and efficient RL as a promising approach for low-cost radiography and X-ray imaging applications.

The utilization of phosphorescent metal cluster complexes as new types of emitting materials in organic light-emitting diodes (OLEDs) is becoming an alternative and viable approach for achieving high-efficiency electroluminescence. We report herein the design of cationic PtAu2 cluster complexes with differently positioned 9-phenylcarbazole-acetylides to serve as phosphorescent emitters in OLEDs. The rigid structures of PtAu2 complexes cause intense phosphorescence with quantum yields of over 85%, which originates from (3)[π(phenylcarbazole-acetylide) → π*(dpmp)] ligand-to-ligand and (3)[π(phenylcarbazole-acetylide) → p/s(PtAu2)] ligand-to-metal charge-transfer triplet excited states. When 8 wt % PtAu2 is doped to blended host materials of TCTA and OXD-7 (2:1 weight ratio) as light-emitting layers, solution-processed OLEDs give a current efficiency of 78.2 cd A(-1) and an external quantum efficiency (EQE) of 21.5% at a practical luminance of 1029 cd m(-2) with a slow efficiency roll-off upon increasing luminance. This represents the best device performance and the highest efficiency recorded at practical luminance for solution-processed OLEDs.

A series of highly phosphorescent PtAg2 heterotrinuclear alkynyl complexes with bis(diphenylphosphinomethyl)phenylphosphine (dpmp) were prepared and characterized structurally. The solution phosphorescence with various emitting colors is systematically modulated by modifying substituents as well as π-conjugated systems in aromatic acetylides. The crystals, powders, or films exhibit reversible stimuli-responsive phosphorescence changes upon exposure to vapor of MeCN, pyridine, DMF, etc., resulting from perturbation of d(8)-d(10) metallophilic interaction in the excited states as a consequence of the formation/disruption of Ag-solvent bonds. Both experimental and time-dependent density functional theory (TD-DFT) studies demonstrate that d(8)-d(10) metallophilic interaction exerts a crucial role on phosphorescent characteristics due to the PtAg2 cluster-based (3)[d → p] state. This study affords a paradigm for phosphorescence modulation in d(8)-d(10) heteronuclear complexes.