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Metal halide perovskite light-emitting diodes (PeLEDs) have been recognized as emerging candidates for next-generation solution-processed electronic display technology, and great progress has been made in recent years. However, their poor operational stability is yet to be solved. Here, we present a reformative all-inorganic red-emission PeLED based on the passivation effect caused by the incorporation of zinc ions into perovskites for enhancing the efficiency and operational stability. A high-quality quasi-two-dimensional perovskite CsPbI3−xBrx thin film with good crystallinity is obtained, benefiting from the combination of large organic ammonium ions (PEA+ ions) and inorganic salt zinc iodide (ZnI2). As a result, ZnI2-passivated CsPbI3−xBrx PeLEDs emitting at 666 nm show a maximum external quantum efficiency of 9.93% and a maximum brightness of 4258 cd m−2. More importantly, the PeLEDs achieve a long half-lifetime of about 2667 h at an initial luminance of 100 cd m−2. This work provides a facile method to obtain stable and efficient red-emission PeLEDs.

Heterometallic chromium(III) CrIII[(SQ-Cat)SbPh3]3 (I), copper(II) CuII[(SQ-Cat)SbPh3]2 (II), and zinc I2Zn(Q-Cat)SbPh3 (III) and IZn(SQ-Cat)SbPh3 (IV) complexes, where SQ is the corresponding o-semiquinone radical anion, and Cat is the catecholate dianion (mono- and direduced forms of the quinone fragment), are synthesized on the basis of the mononuclear triphenylantimony(V) quinone-catecholate complex (Q-Cat)SbPh3, which was derived from 4,4'-di-(6-tert-butyl-3-methylbenzo-1,2-quinone) (Q-Q). The one-electron oxidation and one-electron reduction of chromium complex I afford the paramagnetic derivatives [CrIII[(Q-Cat)SbPh3][(SQ-Cat)SbPh3]2]+ (I+) and [CrIII[(Cat-Cat)SbPh3][(SQ-Cat)SbPh3]2]– (I–), respectively, which are easily detected by EPR spectroscopy. The EPR spectroscopy data and measurements of the temperature dependence of the magnetic susceptibility of copper complex II indicate in favor of the localization of the lone electron on the organic ligand, which can be explained by the antiferromagnetic metal–ligand exchange in this complex (J(SQ-Cu) = –157 cm–1, J(SQ-SQ) = –10.0 cm–1). The coordination of (Q-Cat)SbPh3 as neutral o-quinone to zinc iodide with the formation of complex III increases significantly the oxidation ability of the quinone fragment in this complex (ERed1 = 0.43 V for III and –0.45 V for (Q-Cat)SbPh3 vs. Ag/AgCl/KCl(sat.)), and the complex can oxidize the iodide anion to iodine with the formation of paramagnetic derivative IV, whose EPR spectrum is characteristic of complexes of the M(SQ-Cat) type. The redox properties of complexes I and III are studied by cyclic voltammetry.

A facile synthesis of silicon-containing trimethylsilylated quinolines, 20 from 2-chloro-quinoline-3-carboxaldehyde, 19 are accounted for utilizing trimethylsilyl cyanide (TMSCN) as a reagent, zinc iodide (ZnI2) as a catalyst in dichloromethane (DCM) at room temperature with excellent yields. Further, silylated quinolines, 20 were converted into quinolinyl acetonitriles, 21 in the presence of dilute hydrochloric acid at room temperature in significant yields. Trimethylsilyl cyanide (TMSCN) reacts with aldehyde functional group to form protected silicon ethers as shown in 1HNMR, 13CNMR, and Mass spectral analysis.

Mixed lead-tin halide perovskites have sufficiently low bandgaps (∼1.2 eV) to be promising absorbers for perovskite-perovskite tandem solar cells. Previous reports on lead-tin perovskites have typically shown poor optoelectronic properties compared to neat lead counterparts: short photoluminescence lifetimes (

Undoped PVA and Zinc iodide (ZnI2) inorganic salt doped PVA with different ZnI2 (1–37) wt% percentages are novel composite polymer dielectric films have been successfully prepared by the solution cast method. The developed dielectric films were characterized by analyzing the physicochemical phenomenon to study the effect of ZnI2 inorganic salt concentrations. The XRD histogram explicated the being semi-crystalline nature of PVA polymeric matrix with ZnI2 inorganic salt doping. The optical UV–Vis–NIR characteristics of the composite dielectric films were measured. The effect of ZnI2 inorganic salt loading contents increasing on opto-electrical properties such as transmittance, Absorbance, optical band gap in addition to the AC impedance spectroscopy was studied in the polymer composite dielectric film. The modifications in the optical properties of PVA film are attributed to the interaction between the salt molecules and the PVA matrix. The frequency dependent AC\DC electric conductivity at different ZnI2 content follows and obeyed the Jonscher’s universal power law. The data of AC impedance spectroscopy is to map ready the complex generalization of resistance that includes capacitive and inductive effects of the polymer composite dielectrics as a function of the angular frequency. These films with excellent optoelectronic phenomenon beside appreciable flexibilities aid their claims as multifunctional UV shielding devices with enhanced a character of semiconductors.

Treatment of a series of aromatic hydrocarbons and O-carbethoxy phenol substrates with a mixture of chlorosulfonic acid and dimethoxymethane in CH2Cl2 catalyzed by zinc iodide affords the corresponding chloromethyl derivatives in good to excellent yields.

Having previously established that 1,3-diones could be used as nucleophiles to perform additions to ynamides, highly selective hydroalkoxylation of internal ynamides is now described herein. Several catalytic systems were compared to carry out this transformation including transition metal-based catalysts or Lewis acids. ZnI2 was found to be both very active and highly selective giving only E adducts through a syn addition. Scope and limits investigation showed that this catalyst was compatible with various functional groups. In addition to 17 examples of ynamide hydroalkoxylation, one example of ynamide hydroarylation is reported.

ZnO micro/nanocrystals with different morphologies were synthesized by thermal evaporation of various zinc source materials in an air atmosphere. Zinc acetate, zinc carbonate and zinc iodide were used as the source materials. No catalysts or substrates were used in the synthesis of the ZnO crystals. The scanning electron microscope(SEM) image showed that the morphology of ZnO crystals was strongly dependent on the source materials, which suggests that source material is one of the key factors in controlling the morphology of the obtained ZnO crystals. Tetrapods, nanogranular shaped crystals, spherical particles and crayon-shaped crystals were obtained using different source materials. The X-ray diffraction(XRD) pattern revealed that the all the ZnO crystals had hexagonal wurtzite crystalline structures. An ultraviolet emission was observed in the cathodoluminescence spectrum of the ZnO crystals prepared via thermal evaporation of Zn powder. However, a strong green emission centered at around 500 nm was observed in the cathodoluminescence spectra of the ZnO crystals prepared using zinc salts as the source materials.

A new bidentate Schiff base ligand named as N,N′-bis((E)-3-phenylallylidene)butane-1,4-diamine (L) and three its zinc halide complexes were synthesized and characterized by FT-IR, 1H NMR, 13C NMR and UV–Vis spectroscopy. The crystal structure of zinc bromide and iodide complexes were characterized using single crystal X-ray diffraction. The two structures are isomorphous, crystallizing in the monoclinic crystal system with space group C2/c with closely similar unit cell dimensions. In these complexes, the Zn(II) ion is in the center of a distorted tetrahedral environment completed by two iminic nitrogen atoms of Schiff base ligand and two halide anions. The analysis of crystal structures shows that intermolecular interactions such as C H ⋯ halogen, π ⋯ π and C H ⋯ π interactions have effective role in stabilization of complexes structure. Intermolecular interactions were more analyzed using 3D Hirshfeld surface analysis and corresponding 2D fingerprint plots. Furthermore, structural optimization by DFT calculations at the B3LYP/LANL2DZ level have been performed and then compared with the experimental data. Time-dependent density functional theory (TDDFT) has been also used to calculate the electronic transitions of molecules at B3LYP/LANL2DZ level using the optimized ground-state geometries. NBO analysis was applied for investigation of intra and inter-molecular bonding and conjugative interaction in molecular systems. Schiff base ligand and their zinc complexes have been screened for their antibacterial and antifungal activities by disc diffusion method. Thermal behaviors of all compounds were studied by TG/DTG analysis data. Also, nanostructures of zinc complexes were synthesized by sonochemical method and characterized by FT-IR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). ZnO nanoparticles were simply prepared by calcination of zinc iodide complex as new precursor at 600 °C.

To scrutinize the role of the weak interactions in structure-stability of zinc based metal-organic compounds a series of seventy derivatives were analyzed through single crystal X-ray crystallographic data obtained from IUCr. The structural parameters obtained from the cif file were simulated for molecular dynamics to calculate the weak interactions in series of zinc chloride, zinc bromide, zinc iodide and zinc fluoride based metal-organic composites. The structural frameworks depict that the metal halides are holding the organic moieties within the inorganic patterns through X H … A, C H … π, π … π, halogen-halogen and Metallophilic secondary interactions. The different structural motifs from 1D chain, 2D ribbons and 3D dimmer patterns were observed in the selected series. The comprehensive structural statistics results that the average Zn-X bond distance = 2.375 (4)A [ZnCl2 = 2.465 (4)A, ZnBr2 = 2.396 (4)A, ZnI2 = 2.557 (6)A, ZnF2 = 2.019 (5)A] and X-Zn-X bond angles lie in the range of 64.77–126.45° in these compounds. The X H … A hydrogen bond calculations result the average H … A bond length = 2.38 A [ZnCl2 = 2.37 A, ZnBr2 = 2.44 A, ZnI2 = 2.65 A, ZnF2 = 2.28 A] and the average X H … A bond angle = 125.5° [ZnCl2 = 139°, ZnBr2 = 130.5°, ZnI2 = 119.5°, ZnF2 = 133.5°]. This indicates that these hydrogen interactions are in the category of strong to moderate type of hydrogen bonds. The minimum value of H … π = 2.800 (4) A is observed in ZnBr17 at symmetry position -x, 1-y, 1-z shows that such interactions are stabilizing the organic moieties within the metal-organic derivatives. It is observed that the minimum value of halogen … halogen weak interaction is 2.382 (2)A for ZnF1 at symmetry position -x, 0.5-y, 0.5-z and the minimum value of metallophilic interaction distance is observed as 2.508 (6)A in ZnBr32 at symmetry position,1 + x, y, z, which are linking the inorganic components of metal-organic derivatives. The IR and Raman spectra tensors were calculated for the selected series of derivatives which indicates that IR, Raman and Hyper-Raman modes are dominant in ZnCl2 based derivatives as compared to ZnBr2, ZnI2 and ZnF2 based metal-organic compounds. The structural and spectroscopic parameters reveal that such weak interactions can be used to design the materials with spectroscopic applications.

Usually, when a silylene reacts with a transition metal Lewis acid, it forms an adduct which could be either monomeric or dimeric. However, we present here that a silylene, [PhC(NtBu)2SiN(SiMe3)2] can form both monomeric [PhC(NtBu)2Si{N(SiMe3)2} → ZnI2]·THF (1) and dimeric [{PhC(NtBu)2}(N(SiMe3)2)SiZnI,(μ-I)]2 (2) adducts upon reaction with ZnI2. The formation of 1 and 2 relies upon the solvent used for the reaction or crystallization. When the crystallization is carried out in THF complex 1 is formed, however, when the reaction and crystallization are performed in acetonitrile complex 2 is obtained. Both 1 and 2 were structurally authenticated and the nature of the Si-Zn bond in these complexes was determined by quantum chemical calculations. In addition, a spontaneous inter-conversion between 1 and 2 just by changing the solvents has been also observed; a feature presently not known for silylene-transition metal Lewis adducts.

A key challenge for present-day electric energy storage systems, such as supercapacitors and batteries, is to meet the world's growing demand for high performances, low cost, and environmental-friendliness. Here, we introduce a hybrid energy storage system combining zinc iodide (ZnI2) as redox electrolyte with a nanoporous activated carbon fiber (ACF) cathode and a zinc disk anode. We found that the nanopores (

Alkylzinc reagents prepared from an alkyllithium and zinc iodide were found to undergo coupling with aryl and alkenyl iodides in the presence of LiI in a mixed solvent consisting of THF and diglyme (1:1). Alkyllithiums, prepared by halogen–lithium exchange between an alkyl iodide and tert-butyllithium, are also converted to alkylarenes through alkylzinc reagents.

In this Communication, we developed a new procedure for the synthesis of β‐hydroxysulfides from thiophenols or diaryl disulfides with TBHP as the oxidant. In the presence of zinc iodide or potassium iodide, with TBHP as the oxidant and pre‐reactant, thiophenols and diaryl disulfides reacted with the methyl group of tBuOH smoothly and selectivity to give the corresponding 2‐methyl‐1‐(arylthio)propan‐2‐ols as the terminal products in moderate to good yields.

Some new five coordinated ZnLX2 complexes, where L is N-3-Schiff base ligand obtained by condensation reaction between diethylenetriamine and (E)-3-(2-nitrophenyl)acrylaldehyde and X (Cl-, Br-, I-, N-3(-) and NCS-), were synthesized and characterized by FT-IR, H-1 and (CNMR)-C-13, UV-visible, ESI-mass spectra and molar conductivity measurements. The structures of zinc iodide and thiocyanate complexes were determined by X-ray crystallographic analysis. The X-ray results showed that the Zn (II) center in these complexes is five-coordinated in a distorted trigonal-bipyramidal configuration. Zinc iodide and thiocyanate complexes crystallize in the monoclinic and triclinic systems with space groups of C2/c and P1 with eight and two molecules per unit cell respectively. The crystal packing of the complexes consists of intermolecular interactions such as C-H center dot center dot center dot O and C-H center dot center dot center dot S, N center dot center dot center dot O, together with pi-pi stacking and some other unexpected interactions. The mentioned interactions cause threedimensional supramolecular structure in the solid state. Zinc complexes were also prepared in nano-structure by sonochemical method confirmed by XRD, SEM and TEM analyses. Moreover, ZnO nanoparticles were synthesized by direct thermolysis of zinc iodide complex. Furthermore, antimicrobial and thermal properties of the compounds were completely investigated. (C) 2016 Elsevier B.V. All rights reserved.

Zinc Iodide and Dimethyl Sulfoxide compositions are proposed as therapeutic agents to treat and prevent chronic and acute viral infections including SARS-CoV-2 infected patients. The therapeutic combinations have a wide range of virucidal effects on DNA and RNA containing viruses. The combinations also exhibit anti-inflammatory, immunomodulating, antifibrotic, antibacterial, antifungal and antioxidative effects. Given the fact that Zinc Iodide has been used as an oral antiseptic agent and DMSO has been already proven as a safe pharmaceutical solvent and therapeutic agent, we hypothesize that the combination of these two agents can be applied as an effective, safe and inexpensive treatment for SARS-CoV-2 and other viral infection. The therapeutic compound can be applied as both etiological and pathogenesis therapy and used as an effective and safe antiseptic (disinfectant) for human and animals as well.

The introduction of the redox couple of triiodide/iodide (I3 - /I- ) into aqueous rechargeable zinc batteries is a promising energy-storage resource owing to its safety and cost-effectiveness. Nevertheless, the limited lifespan of zinc-iodine (Zn-I2 ) batteries is currently far from satisfactory owing to the uncontrolled shuttling of triiodide and unfavorable side-reactions on the Zn anode. Herein, space-resolution Raman and micro-IR spectroscopies reveal that the Zn anode suffers from corrosion induced by both water and iodine species. Then, a metal-organic framework (MOF) is exploited as an ionic sieve membrane to simultaneously resolve these problems for Zn-I2 batteries. The multifunctional MOF membrane, first, suppresses the shuttling of I3 - and restrains related parasitic side-reaction on the Zn anode. Furthermore, by regulating the electrolyte solvation structure, the MOF channels construct a unique electrolyte structure (more aggregative ion associations than in saturated electrolyte). With the concurrent improvement on both the iodine cathode and the Zn anode, Zn-I2 batteries achieve an ultralong lifespan (>6000 cycles), high capacity retention (84.6%), and high reversibility (Coulombic efficiency: 99.65%). This work not only systematically reveals the parasitic influence of free water and iodine species to the Zn anode, but also provides an efficient strategy to develop long-life aqueous Zn-I2 batteries.

Thermochemical ester bond cleavage in the phospholipid phosphatidylcholine (PC) was evaluated at reaction temperatures between ca. 20-60 °C using a series of lithium and zinc halides: lithium chloride, lithium bromide, lithium iodide, zinc chloride, zinc bromide, and zinc iodide. Hydroxides, produced via reaction between lithium or zinc halides and potassium hydroxide (KOH), attacked and cleaved selective phosphate and carbonyl ester bonds found in PC. Cleavage reaction efficacy was studied over a wide range of reaction conditions, 2 and 4 hours at 21, 30, 50 and 60 °C, using attenuated total reflectance and transmission FTIR (ATR-FTIR) spectroscopy. FTIR spectral analysis of neat (unreacted) and reacted PC showed qualitative and quantitative evidence of carbonyl and phosphonyl ester bond cleavage as indicated by the appearance and increase in the asymmetric carboxylate anion stretch (∼1577 cm-1) and symmetric phosphonyl dianion stretch (∼1010 cm-1) peaks, respectively. Ester cleavage in PC was demonstrated under extremely mild conditions using lithium hydroxide. In addition, the hydrolysis was found to be selective, leaving the zwitterionic phosphorylcholine group intact. Reaction time and temperature had little to no effect in promoting hydroxide attack on the ester bonds found in PC. Finally, the results of this study show that a non-enzymatic cleavage reaction methodology based on lithium hydroxide can be used for selective ester hydrolysis under extremely mild conditions. This ester hydrolysis method allows for a fast, low temperature, and selective cleavage using a chemical catalyst.

A very high energy density has been reported for the zinc-iodide flow battery [1]. In order to enhance the performance of a zinc-iodide flow battery, an iodide-based complexing agent (1-cyanomethyl-1-methylpyrrolidinium iodide) was added to a 3.0 M ZnI2 electrolyte system. An optimized flow field design for uniform distribution of the electrolyte is desirable for the redox flow battery systems. The impact of flow field design on the performance of the battery was investigated. Charge-discharge characteristics were carried out to investigate cyclability and efficiency of the zinc-iodide battery with and without the presence of complexing agent. The flow cell used graphite felt electrodes, a Nafion membrane, and had an active area of 5 cm2. In this study, the influence of a flow through design, and a flow-by design on the performance of the zinc-iodide flow battery was evaluated. Electrochemical characterization methods, including cyclic voltammetry (CV) and rotating disk electrode (RDE) studies, with and without the presence of complexing agent were performed to evaluate redox potential, diffusion coefficient and electrochemical reversibility of the electrolyte system. The deposited material on the positive and negative electrodes and stability of the electrode material were studied by SEM, EDX, XRD and Raman. [1]- Li, Bin, Zimin Nie, M. Vijayakumar, Guosheng Li, Jun Liu, Vincent Sprenkle, and Wei Wang. "Ambipolar zinc-polyiodide electrolyte for a high-energy density aqueous redox flow battery." Nature communications 6 (2015): 6303.

BACKGROUND The use of CO2 as a raw material to synthesize cyclic carbonates has attracted much attention in recent years. Ionic liquids (ILs) due to their unique properties are often used as effective catalysts for the reaction between CO2 and epoxide to afford cyclic carbonates. This report describes an efficient method for the synthesis of cyclic carbonates in the presence of IL with HSO4− anion as a catalyst which could be easily separated and reused. RESULTS The synthesis of cyclic carbonates from CO2 and epoxides using the two-component catalytic system consisting of the ionic liquid based on the imidazolium cation and the hydrogensulphate anion and an aqueous solution of zinc iodide is described. The cyclic carbonates were obtained with high yields (69–99%) and selectivities (>99%) under the optimized conditions: 120 °C, 2 MPa of CO2, without utilization of any organic solvents. CONCLUSION The new and effective catalytic system allows one to obtain cyclic carbonates in high yields and can be reused several times without significant loss of activity. Therefore, the proposed method seems to be useful for practical applications. © 2016 Society of Chemical Industry

Methyl pyropheophorbides possessing an S-alkylated or arylated sulfanylmethyl group at the 3-position were prepared by the reaction of a 3-hydroxymethyl-chlorin with the corresponding thiols in the presence of zinc iodide. The sulfides were readily oxidized to the corresponding sulfoxides and sulfones and the chlorin was smoothly transformed to its metal complexes. Their Qy absorption maxima in dichloromethane were dependent on the S-functional groups at the 31-position and bathochromically shifted by an increase of their electronegativities. The observation was due to their electron-withdrawing effect through homoconjugation of the 31-substituents with the chlorin π-system via a methylene moiety. Their fluorescence emission quantum yields were similarly affected by the 31-substituents and increased with suppression of the electron-donating ability of the S-atom. The partial fluorescence quenching in the sulfides would be ascribable to photoinduced electron transfer from the 31-S to the singlet excited state of the chlorin moiety in a molecule.

The mechanism of the Zn(II) catalyzed oxidation of benzylic alcohol to benzaldehyde and ester by H2O2 oxidant was investigated through density functional theory methods and compared with the similar oxidation mechanisms of other late transition metals. Both inner sphere and intermediate sphere mechanisms have been analyzed in the presence and absence of pyridine-2-carboxylic acid (ligand). An intermediate sphere mechanism involving the transfer of hydrogen from alcohol to H2O2 was found to be preferred over the competitive inner sphere mechanism involving β-hydride elimination. Kinetic barriers associated with the intermediate sphere mechanism are consistent with the experimental observations, suggesting that the intermediate sphere mechanism is a plausible mechanism under these reaction conditions. The oxidation of alcohols to aldehydes (first step) is kinetically more demanding than the oxidation of hemiacetals to esters (second step). Changing the oxidant to tert-butyl hydrogen peroxide (TBHP) increases the activation barrier for the oxidation of alcohol to aldehyde by 0.4 kcal mol−1, but decreases the activation barrier by 3.24 kcal mol−1 for oxidation of hemiacetal to ester. Replacement of zinc bromide with zinc iodide causes the second step to be more demanding than the first step. Pyridine-2-carboxylic acid ligand remarkably decreases the activation barriers for the intermediate sphere pathway, whereas a less pronounced inverse effect is estimated for the inner sphere mechanism.

Some novel Zn(II) complexes of a new long chain Schiff base ligand have been synthesized. The molecular formula of these complexes is suggested to be ZnLX2 (X = Cl−, Br−, I−, SCN− and N3 −). The ligand and its complexes were identified by elemental analysis, FT-IR, UV–Visible, 1H and 13C NMR spectra, thermogravimetry, conductometry, and melting point measurements. Moreover, the crystal structure of the zinc iodide complex was characterized by X-ray single-crystal analysis. This may be the first report on mononuclear four coordinated Schiff base complex based on 1,4-diaminobutane. The complex crystalizes in the triclinic system with space group P. The zinc ion is surrounded by two iminic nitrogen atoms from the ligand and two iodide anions. According to the angular index of Houser (τ 4) for description of the geometry of four coordinated centers, a distorted tetrahedron is suggested for the complex. Analysis of interactions between molecules of the ZnLI2 complex revealed the existence of intermolecular interactions such as C–H···I, C–H···π, and π···π interactions. There are three types of C–H···I interactions in the crystal packing. Each molecule forms six C–H···I hydrogen bonds with four neighbor molecules through aliphatic and alkenic carbons as donor and I atoms as acceptor. These various C–H···I interactions along with other ones lead to the formation of a supra-molecular structure in a two-dimensional network. After characterization of the complexes, thermal behavior and antimicrobial activities of the ligand and its complexes against some gram-positive and gram-negative bacteria as well as against two fungi were investigated by disk diffusion, MIC, and MBC methods.