Showing papers on "Iodide published in 2013"
TL;DR: It is found that the chemical and physical properties of these materials strongly depend on the preparation method, and the properties of the title hybrid materials with those of the "all-inorganic" CsSnI3 and CsPbI3 prepared using identical synthetic methods.
Abstract: A broad organic–inorganic series of hybrid metal iodide perovskites with the general formulation AMI3, where A is the methylammonium (CH3NH3+) or formamidinium (HC(NH2)2+) cation and M is Sn (1 and 2) or Pb (3 and 4) are reported. The compounds have been prepared through a variety of synthetic approaches, and the nature of the resulting materials is discussed in terms of their thermal stability and optical and electronic properties. We find that the chemical and physical properties of these materials strongly depend on the preparation method. Single crystal X-ray diffraction analysis of 1–4 classifies the compounds in the perovskite structural family. Structural phase transitions were observed and investigated by temperature-dependent single crystal X-ray diffraction in the 100–400 K range. The charge transport properties of the materials are discussed in conjunction with diffuse reflectance studies in the mid-IR region that display characteristic absorption features. Temperature-dependent studies show a ...
4,372 citations
TL;DR: These reactions provide a convenient and straightforward method for the preparation of high-value N-containing products from readily available amine and alkyl iodide precursors.
Abstract: We report an efficient method for the alkylation of γ-C(sp3)–H bonds of picolinamide-protected aliphatic amine substrates with primary alkyl iodides via palladium catalysis. Ag2CO3 and dibenzyl phosphate, (BnO)2PO2H, are critical promoters of this reaction. These reactions provide a convenient and straightforward method for the preparation of high-value N-containing products from readily available amine and alkyl iodide precursors.
322 citations
TL;DR: In this article, the effect of TiO2 film thickness on the charge transport, recombination, and device characteristics of perovskite (CH3NH3)PbI3 sensitized solar cells using iodide-based electrolytes was investigated.
Abstract: We report on the effect of TiO2 film thickness on the charge transport, recombination, and device characteristics of perovskite (CH3NH3)PbI3 sensitized solar cells using iodide-based electrolytes. (CH3NH3)PbI3 is relatively stable in a nonpolar solvent (e.g., ethyl acetate) with a low iodide concentration (e.g., 80 mM). Frequency-resolved modulated photocurrent/photovoltage spectroscopies show that increasing TiO2 film thickness from 1.8 to 8.3 μm has little effect on transport but increases recombination by more than 10-fold, reducing the electron diffusion length from 16.9 to 5.5 μm, which can be explained by the higher degree of iodide depletion within the TiO2 pores for thicker films. The changes of the charge-collection and light-absorption properties of (CH3NH3)PbI3 sensitized cells with varying TiO2 film thickness strongly affect the photocurrent density, photovoltage, fill factor, and solar conversion efficiency. Developing alternative, compatible redox electrolytes is important for (CH3NH3)PbI3 o...
291 citations
TL;DR: For example, this article showed that the reaction of ozone with iodide could account for around 75% of observed iodine oxide levels over the tropical Atlantic Ocean, where bromine and iodine-containing compounds substantially reduce regional and possibly global, tropospheric ozone levels.
Abstract: Naturally occurring bromine- and iodine-containing compounds substantially reduce regional, and possibly global, tropospheric ozone levels. Experimental and model results suggest that the reaction of ozone with iodide could account for around 75% of observed iodine oxide levels over the tropical Atlantic Ocean.
240 citations
TL;DR: A low cost, non-flammable and heavy-metal-free aqueous cathode can contribute to the feasibility of scale-up of lithium-iodine batteries for practical energy storage.
Abstract: Aqueous lithium batteries can store more energy because of their high ionic conductivity compared with the all-solid-state or non-aqueous electrolyte based counterparts. Zhao et al. report a large energy storage density by using safe and low-cost triiodide/iodide redox reaction in an aqueous cathode.
229 citations
TL;DR: Simultaneous evolution of H2 and O2 under visible light was achieved by combining the Pt/H4Nb6O17 semiconductor sensitized with the dye molecules having an oligothiophene moiety, with the IrO2-Pt-loaded WO3 photocatalyst that can reduce the I3(-) back to I(-) and oxidize water to O2.
Abstract: Water splitting into H2 and O2 under visible light was achieved using simple organic dyes such as coumarin and carbazole as photosensitizers on an n-type semiconductor for H2 evolution, a tungsten(VI) oxide (WO3) photocatalyst for O2 evolution, and a triiodide/iodide (I3(-)/I(-)) redox couple as a shuttle electron mediator between them. The results on electrochemical measurements revealed that the oxidized states of the dye molecules having an oligothiophene moiety (two or more thiophene rings) in their structures are relatively stable even in water and possess sufficiently long lifetimes to exhibit reversible oxidation-reduction cycles, while the carbazole system required more thiophene rings than the coumarin one to be substantially stabilized. The long lifetimes of the oxidized states enabled these dye molecules to be regenerated to the original states by accepting an electron from the I(-) electron donor even in an aqueous solution, achieving sustained H2 and I3(-) production from an aqueous KI solution under visible light irradiation when they were combined with an appropriate n-type semiconductor, ion-exchangeable layered niobate H4Nb6O17. The use of H4Nb6O17 loaded with Pt cocatalyst inside the interlayer allowed the water reduction to proceed preferentially with a steady rate even in the presence of a considerable amount of I3(-) in the solution, due to the inhibited access of I3(-) to the reduction site, Pt particles inside, by the electrostatic repulsion between the I3(-) anions and the negatively charged (Nb6O17)(4-) layers. It was also revealed that the WO3 particles coloaded with Pt and IrO2 catalysts exhibited higher rates of O2 evolution than the WO3 particles loaded only with Pt in aqueous solutions containing a considerable amount of I(-), which competitively consumes the holes and lowers the rate of O2 evolution on WO3 photocatalysts. The enhanced O2 evolution is certainly due to the improved selectivity of holes toward water oxidation on IrO2 cocatalyst, instead of undesirable oxidation of I(-). Simultaneous evolution of H2 and O2 under visible light was then achieved by combining the Pt/H4Nb6O17 semiconductor sensitized with the dye molecules having an oligothiophene moiety, which can stably generate H2 and I3(-) from an aqueous KI solution, with the IrO2-Pt-loaded WO3 photocatalyst that can reduce the I3(-) back to I(-) and oxidize water to O2.
224 citations
TL;DR: The role of halide anions in seed-mediated synthesis of anisotropic noble metal nanostructures has been a subject of debate within the nanomaterials community as discussed by the authors.
Abstract: The fundamental role of halide anions in the seed-mediated synthesis of anisotropic noble metal nanostructures has been a subject of debate within the nanomaterials community. Herein, we systematically investigate the roles of chloride, bromide and iodide anions in mediating the growth of anisotropic Au nanostructures. A high-purity surfactant solution of hexadecyltrimethylammonium bromide (CTABr) is used to reliably probe the role of each halide anion without interference from impurities. Our investigation reveals that bromide anions are required for the formation of Au nanorods, while the controlled combination of both bromide and iodide anions are necessary for the production of high-quality Au nanoprisms. Chloride anions, however, are ineffective at promoting anisotropic architectures and are detrimental to nanorod and/or nanoprism growth at high concentrations. We examine the seed structure and propose a growth model based on facet-selective adsorption on low-index Au facets to rationalize the nanost...
182 citations
TL;DR: In this paper, a simple method for the determination of iodide in aqueous solution by exploiting the fluorescence enhancement that is observed if the complex formed between carbon dots and mercury ion is exposed to iodide.
Abstract: We report on a simple method for the determination of iodide in aqueous solution by exploiting the fluorescence enhancement that is observed if the complex formed between carbon dots and mercury ion is exposed to iodide. Fluorescent carbon dots (C-dots) were treated with Hg(II) ion which causes quenching of the emission of the C-dots. On addition of iodide, the Hg(II) ions are removed from the complex due to the strong interaction between Hg(II) and iodide. This causes the fluorescence to be restored and enables iodide to be determined in the 0.5 to 20 μM concentration range and with a detection limit of ~430 nM. The test is highly selective for iodide (over common other anions) and was used for the determination of iodide in urine.
161 citations
TL;DR: A new method of producing carbon-centered radicals was discovered through the reaction of an alkyl iodide with organic salts to reversibly generate the correspondingAlkyl radical (R(•)).
Abstract: A new method of producing carbon-centered radicals was discovered through the reaction of an alkyl iodide (R-I) with organic salts to reversibly generate the corresponding alkyl radical (R•). Via this new reaction, the organic salts were used as new and highly efficient organic catalysts in living radical polymerization. The catalysts included common and inexpensive compounds such as tetrabutylammonium iodide and methyltributylphosphonium iodide. Notably, the catalysts were highly reactive. They enabled the synthesis of high-molecular-weight polymers (up to Mn = 140 000) and the control of acrylate polymerization, which had been difficult with other organic catalysts. The organic salt catalysts were highly versatile, reacting with methacrylate, acrylate, styrene, acrylonitrile, and functional methacrylate monomers. Well-defined block copolymers were also prepared by using this method. A kinetic study quantitatively confirmed the high reactivity of these catalysts. Attractive features of this system includ...
132 citations
TL;DR: The first C2-selective alkynylation of indoles using the hypervalent iodine reagent triisopropylsilylethynyl-1,2-benziodoxol-3(1H)-one (TIPS-EBX) with Pd(II) as a catalyst is described, which gives a single-step access to substituted alkynym indoles with very high C2 selectivity.
127 citations
TL;DR: n-Doping of solution-processible organic semiconductors: highly conductive fullerenes are demonstrated through solution- Processed fulleropyrrolidinium iodide (FPI) and FPI-doped PCBM to reach a high conductivity (3.2 S/m).
Abstract: n-Doping of solution-processible organic semiconductors: highly conductive fullerenes are demonstrated through solution-processed fulleropyrrolidinium iodide (FPI) and FPI-doped PCBM to reach a high conductivity (3.2 S/m). The n-doping proceeds via anion-induced electron transfer between the iodide on FPI and the fullerene in the solid state.
TL;DR: IFAB-ulous trifluoromethylation and CX3·/CX3I precursors for metal-free, visible-light, radical (trifluoro)(iodo)methylations of alkenes are illustrated by their use as photoinitiators for the controlled radical polymerization of vinylidene fluoride with external and in situ generated iodine chain transfer agents.
Abstract: IFAB-ulous trifluoromethylation: (CX3COO)2I(III) h (X=F, H) and (CH3COO)3I(V)(C6H4COO) are introduced as CX3·/CX3I precursors for metal-free, visible-light, radical (trifluoro)(iodo)methylations of alkenes, illustrated by their use as photoinitiators for the controlled radical polymerization of vinylidene fluoride with external (I(CF2)6I) and in situ generated (CF3I) iodine chain transfer agents, and for block copolymer synthesis.
TL;DR: Molecular modelling of an iodine(III) phenoxide was used as a starting point in the design of chiral aryl iodide catalysts for stereoselective oxidative dearomatization reactions.
TL;DR: It is demonstrated that ozone pre-treatment selectively oxidizes iodide to iodate and avoids the formation of iodinated disinfection by-products in iodide-containing waters, in which I-DBPs can be produced upon chlorination or especially chloramination.
TL;DR: Results confirm that the PPT polymer can be applied for the colorimetric as well as fluorometric sensing of I(-) and Hg(2+) ions in a competent environment in solution, aswell as in the solid state, using a membrane film rapidly.
Abstract: A neutral conjugated polymer poly-p-phenylene (PPP) derivative, poly(1,4-bis-(8-(4-phenylthiazole-2-thiol)-octyloxy)-benzene) (PPT), was prepared using a simple and economical method of oxidative polymerization reaction. This newly synthesized polymer PPT was characterized by means of Fourier transform infrared spectroscopy (FT-IR), 1H nuclear magnetic resonance (1H NMR), ultraviolet–visible (UV-Vis), and fluorescence spectroscopy. PPT displays fluorescence “turn-off/turn-on” characteristics and colorimetric responses to I– and Hg2+. The UV-Vis and fluorescence spectra of the PPT showed a significant shift in λmax via the addition of iodides and mercury. A colorless PPT solution turns to deep yellow in the presence of iodide salts, which subsequently becomes colorless again on addition of Hg2+ salts that could be easily detected visually by the naked eye. The Stern–Volmer constant (Ksv) value obtained for the detection of iodide is 0.13 × 105 M–1, confirming very high sensitivity of this polymer for iodid...
TL;DR: In this article, the authors provided experimental, computational and spectroscopic data in support of the direct reactivity of a Pd(I) dimer with an aryl iodide.
Abstract: This report provides experimental, computational and spectroscopic data in support of the direct reactivity of a Pd(I) dimer with an aryl iodide, resulting in Br/I halogen exchange between the complex and the aryl iodide. The reactivity could not be achieved through analogous Pd(0) conditions, demonstrating the distinct reactivities at such multiple Pd-sites. Computational studies support that the direct oxidative addition to ArI by the dinuclear metal complex is energetically feasible.
TL;DR: Solid-state DSSC with the 1-propargyl-3-methylimidazolium iodide as the single-component solid-state electrolyte has achieved a light-to-electricity power conversion efficiency of 6.3% under illumination of simulated AM1.5G solar light and exhibits good long-term stability under continuous 1 sun soaking for 1500 h.
Abstract: Imidazolium iodide is an often used component in iodine-based dye-sensitized solar cells (DSSCs), but it cannot operate an efficient DSSC in the absence of iodine due to its low conductivity. For this study, lamellar solid iodide salts of imidazolium or piperidinium with an N-substituted propargyl group have been prepared and applied in solid-state DSSCs. Owing to the high conductivity arising from the lamellar structure, these solid-state ionic conductors can be used as single-component solid electrolytes to operate solid-state DSSCs efficiently without any additives in the electrolyte and post-treatments on the dye-loaded TiO2 films. With a propargyl group attached to the imidazolium ring, the conductivity is enhanced by about 4 × 104-fold as compared to the alkyl-substituted imidazolium iodide. Solid-state DSSC with the 1-propargyl-3-methylimidazolium iodide as the single-component solid-state electrolyte has achieved a light-to-electricity power conversion efficiency of 6.3% under illumination of simu...
TL;DR: A wide range of indoles undergo cyanation smoothly by employing a reaction system of copper(I) iodide under open-to-air vessels.
Abstract: Copper-mediated direct and regioselective C3-cyanation of indoles using benzyl cyanide as the cyanide anion source is presented. A wide range of indoles undergo cyanation smoothly by employing a reaction system of copper(I) iodide under open-to-air vessels.
TL;DR: A novel colorimetric method for highly sensitive and accurate detection of iodide using citrate-stabilized silver triangular nanoplates (silver TNPs) that has good accuracy, stability and reproducibility comparing with other ordinary colorimetry.
TL;DR: This method was successfully applied to the determination of iodide, iodate and organo-iodine in a variety of water samples, including tap water, seawater, urine and wastewater.
TL;DR: Results showed that most of these model compounds could form a considerable amount of I-DBPs, especially for propanoic acid, butanoic Acid, resorcinol, hydroquinone, alanine, glutamic acid, phenylalanine and serine.
TL;DR: Electrospray ionization coupled to Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) was applied to elucidate the interactions between inorganic iodine species (iodide and iodate) and a fulvic acid (FA) extracted from a SRS surface soil and provides novel evidence to better understand the reactivity and scavenging properties of NOM towards radioiodine and possible influence of N OM on (129)I migration.
TL;DR: New bisoxamato palladate(II) complexes of formula (n -Bu 4 N) 2 [Pd(2-Mepma) 2 ]·4H 2 O (1a) and (n-Bu 4N) 2[Pd 4 N]·2H 2O·MeCN (1b) have been synthesized and characterized by spectroscopic methods and single crystal X-ray diffraction.
TL;DR: In this paper, a series of ionic salts have been investigated to catalyze the coupling reaction between epoxide and carbon dioxide at T = 80 °C and P = 8 MPa among them, they focused particularly on tetrabutylammonium, imidazolium and guanidinium salts.
TL;DR: The results showed that the MB based logic gate is highly selective and sensitive for the detection of Hg(2+) and I(-) over other interfering cations and anions.
Abstract: A simple, rapid, and reversible fluorescent DNA INHIBIT logic gate has been developed for sensing mercury (Hg2+) and iodide (I−) ions based on a molecular beacon (MB). In this logic gate, a mercury ion was introduced as the first input into the MB logic gate system to assist in the hybridization of the MB with an assistant DNA probe through the thymine–Hg2+–thymine interaction, which eventually restored the fluorescence of MB as the output. With this signal-on process, mercury ions can be detected with a limit of detection as low as 7.9 nM. Furthermore, when iodide ions were added to the Hg2+/MB system as the second input, the fluorescence intensity decreased because Hg2+ in the thymine–Hg2+–thymine complex was grabbed by I− due to a stronger binding force. Iodide ions can be detected with a limit of detection of 42 nM. Meanwhile, we studied the feasibility and basic performance of the DNA INHIBIT logic gate, optimized the logic gate conditions, and investigated its sensitivity and selectivity. The results showed that the MB based logic gate is highly selective and sensitive for the detection of Hg2+ and I− over other interfering cations and anions.
TL;DR: In this article, a simple aqueous two-phase system of polyethylene glycol (PEG)/sulphate salt (Na2SO4 or (NH4) 2SO4) was proposed for the selective extraction of Hg(II), Cd(II) and Zn(II).
TL;DR: In this article, the liquid-liquid extraction of toluene from hydrocarbons mixtures (toluene/heptane) was investigated using deep eutectic solvents as solvent.
TL;DR: A simple and reliable colorimetric iodide sensor that based on pH-dependent interaction of silver nanoparticles and H2O2 was developed, which not only innovated the field of iodide recognition but also opened up a novel insight of the application of AgNPs.
TL;DR: In this paper, the performance of dye sensitized nanocrystalline TiO2 solar cells based on quasi-solid state PAN electrolytes containing a series of six quaternary ammonium iodide salts was evaluated.