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Spatial resolution of scintillator is crucial for high‐quality X‐ray imaging, especially in tiny and complicated electronic component. In this work, PrPP2MnBr4 single crystal is obtained by dual‐solvent evaporation method, which gives an unprecedented high spatial resolution of 104.3 lp/mm, representingstate of the art among non‐lead metal halides. The study also conducts the preparation of large area scintillation screen (10 cm × 10 cm) by solidifying melted salt PrPP2MnBr4, thus giving an excellent X‐ray imaging with spatial resolution of 53.5 lp mm−1, which demonstrates its application on large area detection. [ABSTRACT FROM AUTHOR]

It is imminent to develop phosphors with multiple stimuli responses due to the increasing demand on anti‐counterfeiting and information encryption technologies. Here, a zero dimensional (0D) organic–inorganic hybrid (DPPE)2MnBr4·H2O (DPPE = 4,4‐Difluoropiperidine, 1), which emits green light and exhibits reversible thermo‐ and vapor‐luminescence responses to heat and organic solvents is reported. Specifically, when heated above 100 °C for 30 s, hybrid 1 transforms into yellow‐emitting hybrid 2. Upon exposure to dichloromethane (DCM), it transforms into a red‐emitting hybrid 3. Experimental analysis reveals that Mn2+‐Mn2+ magnetic coupling interactions and coordination configuration transformation are responsible for the obvious switching of photoluminescence. Owing to its extraordinary triple‐mode switching characteristics, enabling luminescence‐adjustable transformations such as green to yellow, green to red, and yellow to red emission, this metal‐halide hybrid is promising for the application in anti‐counterfeiting and information encryption. [ABSTRACT FROM AUTHOR]

Circularly polarized electroluminescence (CPEL) is an active area of research because of its wide application in 3D displays and anti‐counterfeiting. However, it is not trivial to obtain a high asymmetry factor for highly efficient CPELs. Herein, a highly efficient CPEL is demonstrated with a superior asymmetry factor by using a chiral phosphine‐oxide‐passivated perovskite film as an emitter. An in situ‐formed perovskite nanocrystalline (NC) film is obtained by passivation of the chiral phosphine oxide. The as‐formed film exhibits much‐enhanced photoluminescence compared with the pristine film. More importantly, the NC film exhibits excellent chiral photoluminescence with a luminescence dissymmetry factor glum as high as 5.6 × 10−3. Electrically driven light‐emitting diodes based on the NC film exhibited superior device performance with a maximum brightness of 18,783 cd m−2 and a peak external quantum efficiency of 3.6%. More encouragingly, an unprecedented electroluminescence asymmetry factor gEL of up to 0.18 is achieved because of the chiral lattice distortion of the perovskite, which is the state‐of‐the‐art among hybrid materials. [ABSTRACT FROM AUTHOR]

Ultra‐long room temperature phosphorescence (ULRTP) materials show valuable applications in encryption, biological imaging, and many other fields. Amazingly, the concomitant impurities from raw materials that are normally ignored contribute dramatically to the ULRTP. In this study, CzPMB [9‐(4‐bromo‐3‐methylphenyl)‐9H‐carbazole] with phosphorescent quantum efficiency of 64% is prepared from commercial carbazole, but the phosphorescent efficiency is drastically reduced to < 2% once trace impurity (5‐(4‐bromo‐3‐methylphenyl)‐5H‐benzo[b]carbazole) is separated. HPLC studies demonstrated the separated impurity is a byproduct derived from trace benzocarbazole in commercial carbazole. Subsequently, the ULRTP for the CzPMB synthesized from lab‐made carbazole is totally unobserved, strongly confirming the dramatic impact of impurity. A defect trapping mechanism in multicomponent system rather than heavy atom effect is proposed for highly efficient ULRTP after carefully analyzing the crystal packings and molecular energy levels. Inspired by this discovery, a series of effective ULRTP bi‐component systems with the highest phosphorescence efficiency of 64.1% are reproduced by directed host‐guest doping. This strategy paves a viable path for the design of organic materials with highly efficient ULRTP. [ABSTRACT FROM AUTHOR]

Sb3+ doping strategy has proved to be an effective way to regulate the band gap and improve the photophysical properties of metal halides. Herein, Sb3+‐doped lead‐free indium halide hybrid InCl6(C4H12N2)2Cl·H2O:xSb3+ (0 ≤ x ≤ 1) is reported. Upon Sb3+‐doping, the weak emission of InCl6(C4H12N2)2Cl experiences a significant enhancement in emission intensity with near‐unity photoluminescence quantum yield (PLQY). The photophysical data fitted by the power‐law equation verifies self‐trapped exciton emission for the broadband emission. Interestingly, the emission experiences a gradual red‐shift with emission color changing from green to yellow and finally to orange as the Sb3+‐doped concentration increases. The single crystal X‐ray diffraction, excitation wavelengths‐dependent emission spectra, and the distortion degree calculation of InCl6(C4H12N2)2Cl·H2O:xSb3+ (0 ≤ x ≤ 1) indicate that the Sb3+ concentration dependent luminescence results from the synergistic effect of crystal phase transition, change of luminescence center, and the distortion of crystal structure. This achievement represents a successful strategy to achieve the photophysical properties modulation of metal halides for versatile optical applications. [ABSTRACT FROM AUTHOR]

The Fano resonance in single‐molecule junctions could be created by interaction with discrete and continuous molecular orbitals and enables effective electron transport modulation between constructive and destructive interference within a small energy range. However, direct observation of Fano resonance remains unexplored because of the disappearance of discrete orbitals by molecule‐electrode coupling. We demonstrated the room‐temperature observation of Fano resonance from electrochemical gated single‐molecule conductance and current–voltage measurements of a para‐carbazole anion junction. Theoretical calculations reveal that the negative charge on the nitrogen atom induces a localized HOMO on the molecular center, creating Fano resonance by interfering with the delocalized LUMO on the molecular backbone. Our findings demonstrate that the Fano resonance in electron transport through single‐molecule junctions opens pathways for designs of interference‐based electronic devices. [ABSTRACT FROM AUTHOR]

It is desirable to develop semiconductors with simultaneously multiple responses to single stimuli. Herein, a thermally responsive hybrid semiconductor (AEV)[Pb2Br8] (AEV4+ = 1,1′‐bis(2‐ammonioethyl)‐[4,4′‐ bipyridine]‐1,1′‐diium) is successfully prepared by introducing functionalized organic cations into 1D lead(II) chains. The lead(II) chain contains an edge‐sharing PbBr6 octahedron with highly electron‐deficient cations distributed in the interspace of the inorganic framework. Interestingly, the as‐formed hybrid exhibits extraordinary thermochromic behavior along with intriguing temperature‐dependent conductivity and thermal conductivity due to the thermal motion of the electrons in the hybrid. Specifically, the color of the pristine hybrid changes from yellow to brown when the temperature rises to 70 °C, and gradually deepens as the temperature continues to rise, accompanied by the continuous decline in electric conductivity and thermal conductivity. Once heating is stopped, the color and conductivity recover to the original state in a few minutes. As demonstrated by electron paramagnetic resonance and X‐ray photoelectron spectroscopy studies, the thermal‐induced electron transfer is likely responsible for the intriguing thermally responsive behaviors. This work provides a paradigm for the modular and functional design of hybrid materials that manifest potential applications in semiconductor refrigeration, thermal power generation, intelligent circuit, and other opt‐electronic devices. [ABSTRACT FROM AUTHOR]

Circular polarized luminescence (CPL)‐active materials attract great attentions owing to their widely applications in 3D optical displays and encrypted transmission. Inspired by the strategies adopted in perovskite based CPL materials, herein, CPL‐active hybrids (D)‐ and (L)‐(tert‐butyl prolinate)MnCl3 were successfully prepared by assembling chiral D/L tert‐butyl prolinate with manganese (II) chloride. Single crystal structures show the as‐formed hybrids possess one‐dimensional (1D) structure containing linear chains of face‐sharing MnCl6 octahedral surrounded by prolinate cations. The 1D Mn(II) hybrids display strong red emission peaked at 646 nm with PLQY of 67.1 % and 57.2 % for d‐type and l‐type, respectively, representing the highest PLQY for 1D MnII hybrids. Interestingly, the 1D Mn(II) hybrids exhibit prominent circular dichroism (CD) signals and remarkable CPL activity with the dissymmetry factor g of 6.1*10−3 and −6.3*10−3 from 550 to 800 nm for (D)‐ and (L)‐(tert‐butyl prolinate)MnCl3, respectively, owing to the existence of chiral cations. It is worthy noted the obtained g represents the highest value for non‐lead organic–inorganic hybrids. [ABSTRACT FROM AUTHOR]

Chiral materials with circularly polarized luminescence (CPL) are currently attracting great attention for their wide applications in bioresponsive imaging, 3D displays, and storage of information. Herein, CPL‐active enantiomorphic hybrids (R)‐ and (S)‐C6H15Cl2NO⋅SbCl5 are obtained by self‐assembling chiral R/S‐(3‐chloro‐2‐hydroxypropyl)trimethylammonium chloride with antimony(III) chloride, giving a 0D structure with SbCl5 pyramids isolated by (3‐chloro‐2‐hydroxypropyl)trimethylammonium chloride cations. The formed enantiomers exhibit brilliant orange emission peaked at 604 nm with photoluminescence quantum yield as high as 71.2%, originating from the self‐trapped exciton emission demonstrated by photophysical characterization. Due to the existence of chiral organic cations, the enantiomers exhibit strong chiral‐optical properties with mirror‐image circular dichroism signals in ground state and obvious CPL activity with the dissymmetry factor glum of 2.5 × 10−4 and −1.6 × 10−4 for R‐type and S‐type, respectively. It should be mentioned that these are the first reported 0D hybrids with CPL‐activity. This work paves an avenue for developing eco‐friendly CPL materials with highly ‐efficient luminescence. [ABSTRACT FROM AUTHOR]

As low‐dimensional lead‐free hybrids with higher stability and lower toxicity than those of three‐dimensional lead perovskites, organic antimony(III) halides show great application potential in opt‐electronic field owing to diverse topologies along with exceptional optical properties. We report herein an antimony(III) hybrid (MePPh3)2SbCl5 with a zero‐dimensional (0D) structure, which exhibits brilliant orange emission peaked at 593 nm with near‐unity photoluminescent quantum yield (99.4 %). The characterization of photophysical properties demonstrates that the broadband emission with a microsecond lifetime (3.24 μs) arises from self‐trapped emission (STE). Electrically driven organic light‐emitting diodes (OLEDs) based on neat and doped films of (MePPh3)2SbCl5 were fabricated. The doped devices show significant improvement in comparison to non‐doped OLEDs. Owing to the much improved surface morphology and balanced carrier transport in light‐emitting layers of doped devices, the peak luminance, current efficiency (CE) and external quantum efficiency (EQE) are boosted from 82 cd m−2 to 3500 cd m−2, 1.1 cd A−1 to 6.8 cd A−1, and 0.7 % to 3.1 % relative to non‐doped devices, respectively. [ABSTRACT FROM AUTHOR]

Abstract: A series of novel diiridium complexes (1–4) bearing both functional 2‐pyrazolyl‐6‐phenyl pyridine chelate and bidentate phenyl imidazolylidene chelate are synthesized, for which the pyrazolate fragment of the tridentate 2‐pyrazolyl‐6‐phenyl pyridine also behaves as the bridge to hold two iridium atoms in close vicinity. Their structure is unambiguously confirmed using X‐ray structure determination on the corresponding derivative 2a bearing 1,3‐bis(4‐fluorophenyl)‐1H‐Imidazolyl cyclometalate. Their photophysical and electrochemical properties are studied and further affirmed by the computational approaches. All these Ir(III) metal complexes 1–4 are very stable in both solution and solid film with near unity emission quantum efficiency. As opposed to most of diiridium complexes documented in literature, 1–4 are volatile and suitable for fabrication of organic light emitting diodes (OLEDs) under vacuum evaporation. The corresponding electroluminescent devices exhibit superior performance, among which external quantum efficiency of 27.6% using 2 as dopant stands for the record high of OLEDs using dinuclear Ir(III) complexes. They also offer a low roll‐off at high luminance, demonstrating their potential en route to high performance OLEDs. [ABSTRACT FROM AUTHOR]

Abstract: An elaborately designed pyridinium‐functionalized octanuclear zinc(II) coordination container 1‐Zn was prepared through the self‐assembly of Zn2+, p‐tert‐butylsulfonylcalix[4]arene, and pyridinium‐functionalized angular flexible dicarboxylate linker (H2BrL1). The structure was determined by a single‐crystal X‐ray diffractometer. 1‐Zn displays highly sensitive and specific recognition to 2‐picolylamine as revealed by drastic blueshifts of the absorption and emission spectra, ascribed to the decrease of intramolecular charge transfer (ICT) character of the container and the occurrence of intermolecular charge transfer between the host and guest molecules. The intramolecular charge transfer plays a key role in the modulation of the electronic properties and is tunable through endo‐encapsulation of specific guest molecules. [ABSTRACT FROM AUTHOR]

Abstract: Developing ternary metal oxides as electron transport layers (ETLs) for perovskite solar cells is a great challenge in the field of third‐generation photovoltaics. In this study, a highly mesoporous Zn2Ti3O8 (m‐ZTO) scaffold is synthesized by ion‐exchange method and used as ETL for the fabrication of methyl ammonium lead halide (CH3NH3PbI3) perovskite solar cells. The optimized devices exhibit 17.21 % power conversion efficiency (PCE) with an open circuit voltage (Voc) of 1.02 V, short‐circuit current density (Jsc) of 21.97 mA cm−2 and fill factor (FF) of 0.77 under AM 1.5G sunlight (100 mW cm−2). The PCE is significantly higher than that based on mesoporous ST01 (m‐ST01; 10 nm TiO2 powder) layer (η=14.93 %), which is ascribed to the deeper conductive band of ZTO nanoparticles, better light absorption and smaller charge recombination. The devices stored for 100 days at ambient temperature with humidity of 10 % showed excellent stability with only 12 % reduction of the PCE. The charge transmission kinetic and long‐term stability parameters of the ZTO‐based perovskite film growth are discussed as well. [ABSTRACT FROM AUTHOR]

An Fe2+-responsive bimodal MRI and fluorescent imaging probe, Gd-DTTA-BPP (DTTA = diethylenetriamine- N, N, N″, N″-tetraacetate, BPP = 2-{4-[(2,2′-bipyridin)-5-ylethynyl]phenoxy}- N-ethylacetamide), has been synthesized and characterized and its relaxivity and fluorescence properties examined. Gd-DTTA-BPP displays a high relaxation efficiency (10.3 m M-1 s-1 at 23 MHz and 25 °C) as a result of its rigid ligand and two inner-sphere water molecules ( q = 2). In the presence of 1.0 equiv. Fe2+, the relaxation efficiency increased from 10.3 to 13.6 m M-1 s-1 (23 MHz and 25 °C) due to the complexation of Gd-DTTA-BPP with Fe2+. The fluorescence emission of the Gd-DTTA-BPP complex is quenched by Fe2+ ions. The confocal fluorescence imaging experiments on living cells showed that the imaging probe is permeable to living cells and localizes in the cytoplasm. [ABSTRACT FROM AUTHOR]

Cationic Au4Ag2 heterohexanuclear aromatic acetylides cluster complexes supported by bis(2-diphenylphosphinoethyl)phenylphosphine (dpep) are prepared. The Au4Ag2 cluster structure originating from the combination of one anionic [Au(C≡CR)2]− with one cationic [Au3Ag2(dpep)2(C≡CR)2]3+ through the formation of Ag−acetylide η2-bonds is highly stabilized by Au-Ag and Au-Au contacts. The Au4Ag2 alkynyl cluster complexes are moderately phosphorescent in the fluid CH2Cl2 solution, but exhibit highly intense phosphorescent emission in solid state and film. As revealed by theoretical computational studies, the phosphorescence is ascribable to significant 3[π (aromatic acetylide) → s/p (Au)] 3LMCT parentage with a noticeable Au4Ag2 cluster centered 3[d → s/p] triplet state. Taking advantage of mCP and OXD-7 as a mixed host with 20 wt% dopant of phosphorescent Au4Ag2 cluster complex in the emitting layer, solution-processed organic light-emitting diodes (OLEDs) exhibit highly efficient electrophosphorescence with the maximum current, power, and external quantum efficiencies of 24.1 cd A−1, 11.6 lm W−1, and 7.0%, respectively. Introducing copper(I) thiocyanate (CuSCN) as a hole-transporting layer onto the PEDOT:PSS hole-injecting layer through the orthogonal solution process induces an obvious improvement of the device performance with lower turn-on voltage and higher electroluminescent efficiency. [ABSTRACT FROM AUTHOR]

Heteronuclear complexes FeCp2DTECCRu(dppe)2Cl ( 1 o; dppe=1,2-bis(diphenylphosphino)ethane, Cp=cyclopentadienyl, DTE=dithienylethene) and FeCp2DTECCRu(dppe)2CCDTEFeCp2 ( 2 oo), with redox-active ferrocenyl and ruthenium centers separated by a photochromic DTE moiety, were prepared to achieve photoswitchable charge delocalization and Fe⋅⋅⋅Ru electronic communication. Upon UV-light irradiation of 2 oo, the Fe⋅⋅⋅Ru heterometallic electronic interaction is increasingly facilitated with stepwise photocyclization, 2 oo→ 2 co→ 2 cc; this is ascribed to the gradual increase in π-conjugated systems. The near-infrared absorptions in mixed-valence species [ 2 oo]+/[ 2 co]+/[ 2 cc]+ are gradually intensified following the conversion of [ 2 oo]+→[ 2 co]+→[ 2 cc]+, which demonstrates that the extent of charge delocalization shows progressive enhancement with stepwise photocyclization. As revealed by electrochemical, spectroscopic, and theoretical studies, complex 2 exhibits nine switchable states through stepwise photochromic and reversible redox processes. [ABSTRACT FROM AUTHOR]

The gadolinium(III) complexes GdL1 and GdL2 were designed as Zn2+-responsive bimodal magnetic resonance imaging (MRI) and fluorescence imaging probes. Upon binding to Zn2+ ions, GdL1 exhibits a bidentate or tridentate mode to form heterodinuclear GdL1Zn or heterotrinuclear (GdL1)2Zn, whereas GdL2 binds to the Zn2+ ion only in a bidentate mode to form (GdL2)2Zn. The gadolinium(III) complexes derived from both H3L1 and H3L2 exhibit remarkable interactions with human serum albumin (HSA) at both site I and site II, which result in significant enhancements of the relaxivity and remarkable improvements of T1-weighted imaging contrast. In the presence of HSA, both the relaxivity (r1) and fluorescence exhibit 300% enhancement with a clear blueshift of the fluorescence for GdL1Zn, which is ascribed to direct binding to HSA through the formation of a Zn-HSA coordination bond. In contrast, the presence of HSA induces smaller relaxivity increases for GdL1 (155%), (GdL1)2Zn (183%), GdL2 (192%), and (GdL2)2Zn (181%); these increases are ascribed to weaker hydrophobic interactions or stereospecificity with HSA. The contrast of T1-weighted phantom MR images of these gadolinium(III) complexes in human serum (HS) is much improved relative to that in 4-(2-hydroxyethyl)- 1-piperazineethanesulfonic acid (HEPES) buffer solutions. [ABSTRACT FROM AUTHOR]

A series of platinum(II) complexes bearing 1,3-bis(2-pyridylimino)isoindoline (BPI) derivatives as ligand have been prepared by substitution of the coordinated Cl in precursors [Pt(L)Cl] [L = L1 ( 1), L2 ( 2), L3 ( 3)] by a monodentate strong-field ligand such as CN-, CN-cyclohexyl, PPh3, NCS-, PhS-, or N(CN)2-. Most of these compounds display orange-to-red luminescence in both the solid state and solution at ambient temperature. Compared with precursors 1- 3, both low-energy absorption and emission bands in ligand-substituted platinum(II) complexes 4- 13 exhibit distinct blueshifts. The emission of platinum(II) complexes with CN-containing monodentate ligands shows progressive blueshifts with increasing ligand field strength: 609 ( 10, NCS-) → 603 [ 12, N(CN)2-] → 590 ( 4, CN-) → 581 nm ( 7, C≡N-cyclohexyl). The emission of complexes 4- 9 originates mainly from the 3[π → π*(BPI)] 3IL triplet excited state, mixed with some 3[dπ(Pt) → π*(BPI)] 3MLCT character. In contrast, the emission of 10- 13 arises from a clearly increased 3[π(L) → π*(BPI)] 3LLCT state with reduced 3[π → π*(BPI)] 3IL and 3[5d(Pt) → π*(BPI)] 3MLCT character. Noticeably, dicyanamido-linked dinuclear complex 13 displays a significant ligand-ligand electronic interaction between the two BPI across the Pt-N≡C-N-C≡N-Pt bridge with remarkable LLCT character from one BPI to the other. [ABSTRACT FROM AUTHOR]

Hetero‐metal doping or substitution to create alloy clusters is a highly appealing strategy for improving physicochemical characteristics as well as tailoring optical and electronic properties, although high‐yield synthesis of alloy clusters with precise positioning of doped metals is a daunting challenge. Herein, we manifest rational synthesis of chiral alloy cluster enantiomers R/S‐Ag6Cu in 85 %–87 % yield by replacing one Ag(I) atom with Cu(I) in homometallic clusters R/S‐Ag7, achieving circularly polarized luminescence (CPL) with a quantum yield beyond 90 %. As a small energy gap (ca. 0.07 eV) between S1 and T1 states facilitates thermally activated delay fluorescence (TADF) through reverse intersystem crossing (RISC), the photoluminescence (PL) of R/S‐Ag7 and R/S‐Ag6Cu at ambient temperature originates mostly from TADF (85 % and 86 %) in place of phosphorescence (15 % and 14 %). Relative to those of R/S‐Ag7, copper(I) doping not only triples PL quantum yields of R/S‐Ag6Cu due to accelerating ISC (intersystem crossing) and RISC, but also doubles CPL asymmetry factors of R/S‐Ag6Cu ascribed to rigidizing cluster structure through stronger Ag−Cu interaction apart from dramatically improving thermodynamic stability. Solution‐processable circularly polarized organic light‐emitting diodes (CP‐OLEDs) demonstrate high‐efficiency circularly polarized electroluminescence (CPEL) with external quantum efficiency (EQE) of 26.7 %, which is superior to most of red‐emitting OLEDs through solution process. [ABSTRACT FROM AUTHOR]

The title compound, C18H12N4O·H2O, adopts the keto tautomeric form and the azomethine C=N double bond is in the E configuration. The dihedral angle between the planes of the di­aza­fluorene moiety and the phenyl ring is 11.3 (1)°. In the solid state, the mol­ecules form infinite chain-like structures via O-H⋯N hydrogen bonds involving the water mol­ecules and di­aza­fluorene moieties. [ABSTRACT FROM AUTHOR]

The reaction between [Cu2(μ-bis­(diphenyl­phosphino)­methane)2­(MeCN)2](ClO4)2 and (Bu4N)2[ W( cis-1,2-dicyano­ethyl­ene-1,2-dithiol­ate)3] gave the title compound, {[Cu2W(C4N2S2)3(C2H3N)(C25H22P2)2]·2C4H10O·C2H3N} n. Due to the binding between a Cu atom of the binuclear copper unit [Cu2{bis(diphenylphosphino)methane}2(MeCN)]2+ and the N atoms of the buliding block [W( cis-1,2-dicyano-ethylene-1,2-dithiolate)3]2−, a one-dimensional zigzag chain structure is formed. [ABSTRACT FROM AUTHOR]

Reaction of (Bu4N)2[Mo(mnt)3] (mnt = cis-1,2-dicyano­ethyl­ene-1,2-dithiol­ate) with [Cu2(dppa)2(MeCN)4](ClO4)2 [dppa = bis­(diphenyl­phosphino)amine] yields the polymeric heterometallic title compound, {[Cu2Mo(mnt)3(μ-dppa)2(MeCN)2]·2CH3CN} n or {[Cu2Mo(C4N2S2)3(C24H21NP2)2(C2H3N)2]·2C2H3N}. The compound exhibits a polymeric zigzag structure formed from [Mo(mnt)3]2− and [Cu2(dppa)2(MeCN)2]2+ units linked by coordination of the CN groups of the mnt ligands to the CuI centres. [ABSTRACT FROM AUTHOR]