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Jimmy Wang; Matthew A. Horwitz; Alexander B. Dürr; Francesco Ibba; Gabriele Pupo; Yuan Gao; Paolo Ricci; Kirsten E. Christensen; Tejas P. Pathak; Timothy D. W. Claridge; Guy C. Lloyd-Jones; Robert S. Paton; Véronique Gouverneur
Lewis acids; Lewis bases; X-ray diffraction; catalysts; catalytic activity; cations; enantiomers; enantioselectivity; fluorides; hydrogen; hydrogen bonding; nitrogen; nuclear magnetic resonance spectroscopy; sodium azide; stereoselective synthesis; urea
Abstract:
... Asymmetric catalytic azidation has increased in importance to access enantioenriched nitrogen containing molecules, but methods that employ inexpensive sodium azide remain scarce. This encouraged us to undertake a detailed study on the application of hydrogen bonding phase-transfer catalysis (HB-PTC) to enantioselective azidation with sodium azide. So far, this phase-transfer manifold has been app ...
... peri-Substituted naphthalene complexes (Trip₂Pn)₂Naph (Pn = Sb 1, Bi 2) were synthesised and their redox behaviour investigated. Oxidation of 1 with [Fc][BArF] (BArF = B(C₆F₅)₄) yielded [(Trip₂Sb)(TripSb)Naph][BArF] (3) containing the stibane-coordinated stibenium cation [(Trip₂Sb)(TripSb)Naph]⁺. Subsequent reduction of 3 with KC₈ yielded distibane (TripSb)₂Naph (4). 1–4 were characterised by NMR ...
... Ga- and In-exchanged chabazite (CHA) zeolites with same Si/Al and metal/Al ratios were prepared via the incipient wetness impregnation method, were characterized using N₂ adsorption, electron microscopy, temperature-programed reactions and were evaluated for the ethane dehydrogenation reaction using flow microreactors. Ga-CHA has higher reaction rates and a lower activation energy of 107 kJ/mol th ...
Xiaofeng Chen; Haomiao Xie; Emmaline R. Lorenzo; Charles J. Zeman; Yue Qi; Zoha H. Syed; Aaron E. B. S. Stone; Yao Wang; Subhadip Goswami; Peng Li; Timur Islamoglu; Emily A. Weiss; Joseph T. Hupp; George C. Schatz; Michael R. Wasielewski; Omar K. Farha
X-ray diffraction; acetone; cations; density functional theory; electron paramagnetic resonance spectroscopy; imidazole; infrared spectroscopy; irradiation; magnetism; solvents; topology; ultraviolet radiation
Abstract:
... Owing to their switchable spin states and dynamic electronic character, organic-based radical species have been invoked in phenomena unique to a variety of fields. When incorporated in solid state materials, generation of organic radicals proves challenging due to aggregation. Metal–organic frameworks (MOFs) are promising candidates for immobilization and stabilization of organic radicals because ...
Jana Glatz; Juan-Ramón Jiménez; Louis Godeffroy; Hans Jurgen von Bardeleben; Laure Fillaud; Emmanuel Maisonhaute; Yanling Li; Lise-Marie Chamoreau; Rodrigue Lescouëzec
... FeCo Prussian blue analogues of general formula AₓCoy[Fe(CN)₆]z are responsive, non-stoichiometric materials whose magnetic and optical properties can be reversibly switched by light irradiation. However, elucidating the critical influence of the inserted alkali ion, A⁺, on the material’s properties remains complicated due to their complex local structure. Here, by investigating soluble A ⊂ [Fe₄–C ...
... The development of high-performing p-type transparent conducting oxides will enable immense progress in the fabrication of optoelectronic devices including invisible electronics and all-oxide power electronics. While n-type transparent electrodes have already reached widespread industrial production, the lack of p-type counterparts with comparable transparency and conductivity has created a bottle ...
... The issue of effluent, especially organic colorants from several manufacturing units overlays an immense delinquent of the current epoch owing to its effect on oncogenic health hazards. Thus, Rare Earth Metal dysprosium (Dy) doped Zinc Ferrite (ZnFe₂O₄) were as-synthesized by a facile co-precipitation technique as an effectual nano photocatalyst intended to the amputation of these noxious dyes. Th ...
World Health Organization; X-radiation; X-ray diffraction; aquifers; cations; clay; coliform bacteria; electrical resistance; environmental impact; fluorescence; gravel; groundwater contamination; laterites; particle size distribution; permeability; risk; sand; silt; specific gravity; streams; topography; water analysis; water content; water hardness; wetlands; Nigeria
Abstract:
... Improper sitting positioning of cemeteries in Nigeria is mostly responsible for groundwater pollution. Poor water quality may lead to some communicable diseases in most rural and urban areas of the southwestern part of Nigeria. The environmental impact of cemeteries close to residential areas within the Edunabon metropolis, southwestern part of Nigeria, was assessed. The research is aimed to under ...
... Ionic liquids (ILs) have been introduced as novel high-performance shale inhibitors. The inhibition performance and mechanism of the cation groups in ILs have been widely investigated, whereas the effects of the anionic groups in ILs on the inhibitory capacity have rarely been reported. In this work, a series of fatty acid-based ionic liquids (FAILs) with different anionic groups, methyltrioctylam ...
... The crystal structure of a copper(II) complex of protonated sildenafil, CuCl₃C₂₂H₃₁N₆O₄S⋅2H₂O was studied by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P2₁/n with the unit cell parameters a = 15.4292(2), b = 9.06735(12), c = 21.1752(2) Å, V = 2945.48(7) ų, Z = 4. The Cu atom is coordinated by the sildenafil ligand via the N2 atom of the pyrazolopyrim ...
... Organic–inorganic hybrid perovskites have various potential applications in fuel cells and solar cells. In this regard, the physicochemical properties of an organic–inorganic [NH₃(CH₂)₆NH₃]CuCl₄ crystal was conducted. The crystals had a monoclinic structure with space group P2₁/n and lattice constants a = 7.2224 Å, b = 7.6112 Å, c = 23.3315 Å, β = 91.930°, and Z = 4 at 300 K, and the phase transit ...
... A series of novel semiconductors AAe₆Si₁₂P₂₀X (A = Na, K, Rb, Cs; Ae = Sr, Ba; X = Cl, Br, I) is reported. Their crystal structures feature a tetrahedral Si–P framework with large zeolite-like pores hosting two types of cations, monoatomic A⁺ and unprecedented octahedral X@Ae₆¹¹⁺. Mixing of the A and Ba cations was detected by single crystal X-ray diffraction and confirmed by multinuclear solid st ...
... In the present study, glutaraldehyde was used as a hydrophobic modifier to crosslink polyvinyl alcohol (PVA), and copper ion was immobilized by sodium alginate (SA). Polyvinyl alcohol-copper alginate (PVA-CA) gel beads were prepared by a one-step process, and were used to adsorb and remove tetracycline (TC) from an aqueous solution. The beads were characterized by scanning electron microscopy (SEM ...
... Structural, elastic and cation distribution properties have been investigated on stoichiometric and non-stoichiometric cobalt ferrites. Crystal structure, formation of spinel type ferrite, chemical bonding, cation distribution, and thermal properties of two series of Cr³⁺ substituted stoichiometric and non-stoichiometric various cobalt ferrites with general formula Co₁₋ₓCrₓFe₂O₄ (S1), and Co₁₊ₓCrₓ ...
... Ternary rare-earth hydride oxides (or oxyhydrides) REHO show rather high thermal stability and inertness in air. SmHO remained intact when stored in air for 12 h, while after storage for one year, it completely hydrolysed to form Sm(OH)₃. In contrast, YHO and HoHO show only slight decomposition upon longer storage. The cation’s basicity and the air humidity apparently are crucial factors in the ai ...
X-ray diffraction; ammonium thiocyanate; anisotropy; cations; crystal structure; dielectric spectroscopy; electric potential difference; photoluminescence; relative humidity; van der Waals forces
Abstract:
... Two-dimensional (2D) metal halide perovskites have recently emerged as promising photovoltaic materials due to their superior ambient stability and rich structural diversity. However, power conversion efficiencies (PCEs) of the 2D perovskites solar cells (PSCs) still lag behind their three-dimensional (3D) counterpart, particularly due to the anisotropy in the charge carrier mobility and inhomogen ...
... The triangulo-{Er₃} complex [Er₃Cl(o-van)₃(OH)₂(H₂O)₅]Cl₃·nH₂O (n = 9.4; H(o-van) = o-vanillin) (1) was generated by an in situ method. The isolated Er(iii) complex 1 was characterized by elemental analysis and molecular spectroscopy. The results of single crystal X-ray diffraction studies have shown that 1 is built up of trinuclear [Er₃Cl(o-van)₃(OH)₂(H₂O)₅]³⁺ complex cations, chloride anions and ...
... The introduction of new energy levels in the forbidden band through the doping of metal ions is an effective strategy to improve the thermal stability of TiO₂. In the present study, the impact of Ta doping on the anatase to rutile transition, structural characteristics, and anion and cation vacancy formation were investigated in detail using density functional theory and experimental characterizat ...
... In this work, sodium bentonite was silylated with 3-aminopropyltrimethoxysilane (APTMS) under microwave irradiation at 50 °C at different times (5, 10 and 15 min). Silylation was performed in presence and absence of ethylene glycol. Infrared and ²⁹Si NMR spectroscopies were used to monitor the grafting process, while the degree of functionalization was calculated by using CHN elemental analysis an ...
... The reaction of Bi, BiBr₃, and CuBr in the Lewis-acidic ionic liquid [BMIm]Br·4AlBr₃ (BMIm = 1-n-butyl-3-limidazolium) at 180 °C yielded air-sensitive, shiny black crystals of (CuBi₈)[AlBr₄]₂[Al₂Br₇]. Crystals of [MBi₁₀][AlCl₄]₄ (M = Pd, Pt) were obtained by reacting Bi, BiCl₃, and MCl₂ under similar conditions. The structures have been determined by X-ray diffraction on single-crystals and were f ...
... Boroles and borapyramidanes are classical and nonclassical constitutional isomers, respectively. It is here shown that they can indeed be interconverted. Treatment of the bis(alkynyl)B(C₆F₅) SMe₂ adduct 3·SMe₂ with HB(C₆F₅)₂ gave borole 1·SMe₂, featuring trimethylsilyl substituents in both α positions to boron, by means of a 1,1-hydroboration/alkenylboration sequence. Photolysis of the classical b ...
... Four types of ionic liquids (ILs) of [X]TFSI ([X]⁺ is a cation such as 1-butyl-3-methylimidazolium BMIm⁺, 1-butyl-1-methylpyrrolidinium BMPyrr⁺, 1-butyl-1-methylpiperidinium BMPip⁺ and methyltrioctylammonium MOc₃Am⁺ and TFSI⁻ is the bis(trifluoromethylsulfonyl)imide anion) were confined in halloysite nanoclay (Hal) at an excess ionic liquid concentration (IL : Hal ∼55 : 45 wt%) and studied by X-ra ...
... H₄SiW₁₂O₄₀ (HSiW) was supported on mesoporous silica (SBA-15), non-structured amorphous silica (AEROSIL) and γ-alumina (Al₂O₃) by impregnation. The supported HSiW samples were characterized by X-ray diffraction (XRD), N₂ adsorption-desorption isotherms, infrared (IR) spectroscopy and ethanol dehydration reaction as a model reaction. HSiW was not highly dispersed even at 29 wt% loading, but the hex ...
Epilobium angustifolium; X-ray diffraction; antioxidant activity; bioprocessing; cations; cryogels; freeze drying; gelatin; migratory behavior; polyphenols; water vapor; whey protein isolate
Abstract:
... Gelatin (GEL) and whey protein isolate (WPI) are often taken into account as carriers of phytoantioxidants for developing active packaging. The materials obtained, however, have not yet been systematically compared to demonstrate their potential benefits and drawbacks. Fireweed extract (FE) is a rich source of polyphenols with high antioxidant activity. Therefore, in this study, the structural, ph ...
X-ray absorption spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; cathodes; cations; electric vehicles; energy; energy density; lithium; temperature; transmission electron microscopy
Abstract:
... Ni-rich high-energy-density lithium ion batteries pose great risks to safety due to internal short circuits and overcharging; they also have poor performance because of cation mixing and disordering problems. For Ni-rich layered cathodes, these factors cause gas evolution, the formation of side products, and life cycle decay. In this study, a new cathode electrolyte interphase (CEI) for Ni²⁺ self- ...
... A ZnS nano-sorbent to remove copper(II) and lead(II) ions from aqueous solutions was prepared via a hydrothermal reaction and characterized by X-ray diffraction. The zinc sulfide nanoparticle size was determined to be 7.0 ± 0.22 nm. The effects of pH, light conditions, time, capacity, and interferences on the zinc sulfide ability to remove copper(II) and lead(II) ions from aqueous solutions were i ...
Liudmila A. Gorelova; Anna S. Pakhomova; Maria G. Krzhizhanovskaya; Dmitrii V. Pankin; Sergey V. Krivovichev; Leonid S. Dubrovinsky; Anatoly V. Kasatkin
... The high-pressure behavior of slawsonite, SrAl₂Si₂O₈, has been studied using in situ single-crystal X-ray diffraction (SCXRD) and Raman spectroscopy up to 31 GPa. Slawsonite undergoes displacive phase transition between 6 and 8 GPa with the formation of slawsonite-II, featuring fivefold coordinated silicon and aluminum. The results have been confirmed by the changes in vibrational modes using Rama ...
... Potassium 15-crown-5 phenanthrenide and potassium 18-crown-6 phenanthrenide were synthesized and characterized by powder X-ray diffraction and ³⁹K solid state NMR spectroscopy. While the radical carbanion is very reactive in solution, the crystals are stable and storable under inert atmosphere. For 15-crown-5, a sandwich-like complex of potassium is formed with two molecules of crown ether per pot ...
... Nanocrystalline CuFe₂O₄ was synthesized through stotiometric mixing of aqueous solutions of Cu(NO₃)₂. 3H₂O and Fe(NO₃)₃. 9H₂O mediated by α-Lactose monohydrate (C₁₂H₂₂O₁₁.H₂O) as reductant. Aqueous NaOH solution was used as the catalyst and the reaction was carried out at room temperature. The ageing of crystallites in cubic spinel structure was accomplished by annealing the powder sample at 600 ° ...
... Phase-pure copper(II) cyanoguanidine bromide hydrate, Cu(C₂N₄H₄)₂Br₂·2H₂O (1), was precipitated from aqueous solution and its structure was solved and refined from single-crystal X-ray diffraction data at 100 K. 1 crystallizes in space group P2₁/n with a = 12.09(3) Å, b = 3.925(9) Å, c = 13.79(3) Å, β = 96.62(6)°, Z = 2, and V = 650(2) ų. The copper(II) cation is coordinated by two cyanoguanidine ...
... We present a complete structural study of the successive phase transitions observed in the YBaMn₂O₆ compound with the layered ordering of cations on the perovskite A-site. We have combined synchrotron radiation X-ray powder diffraction and symmetry-adapted mode analysis to describe the distorted structures as pseudosymmetric with respect to the parent tetragonal structure. The YBaMn₂O₆ compound sh ...
Raman spectroscopy; X-ray diffraction; absorption; atomic force microscopy; case studies; cations
Abstract:
... In spite of environmental stability and toxic-free merits, the performance of double perovskite solar cells (Cs₂AgBiBr₆ to be specific) has not excelled due to their large indirect band gap, low absorption of solar spectrum, and more importantly hurdles in carrier transport processes. A large number of intrinsic defects and self-trapped excitons (STE) appear in the double perovskite due to a disor ...
Fourier transform infrared spectroscopy; X-ray diffraction; acetates; acidity; catalysts; catalytic activity; cations; crystal structure; desorption; ion exchange; nuclear magnetic resonance spectroscopy; porosity; porous media; process design; steam; zeolites
Abstract:
... A series of dealuminated mordenite (MOR) samples with different acidities and various porosities were prepared through steam treatment of H⁺/Na⁺ mordenite. The obtained zeolites were elaborately characterized by X-ray diffraction, N₂ adsorption–desorption, scanning electron microscopy, ²⁹Si nuclear magnetic resonance (NMR), ²⁷Al NMR, NH₃ temperature-programmed desorption, and Fourier transform inf ...
X-ray diffraction; cathodes; cations; chromium; crystal structure; electric potential difference; electrochemistry; energy density; fluorine; industry; lithium; transmission electron microscopy
Abstract:
... Li-rich layered oxides are identified as the most promising cathode material for lithium ion batteries due to their high specific capacity and energy density. However, capacity fading, voltage decay and inferior rate capability have restricted its development in industry. Herein, we developed a novel cation/anion (chromium/fluorine) co-doping methods to enhance the electrochemical performance of L ...
... Grinding, an essential pretreatment procedure before flotation, has particularly significance in spodumene flotation. The effects of grinding media on the flotation behavior of spodumene were investigated through zeta potential measurement, X-ray diffraction (XRD) test, scanning electron microscopy combined with energy dispersive spectrometry (SEM-EDS) and X-ray photoelectron spectroscopy (XPS). T ...
... Under mild conditions with a cation ratio of 1:1, Zn-Co layered double hydroxide (LDH) nanosheets were synthesized by co-precipitation. The effect of temperature on the physicochemical properties of LDH at 80, 300, and 500 ∘C was studied using x-ray diffraction (XRD), BET surface area, High resolution-Transmission electron microscopy (HR-TEM), Field Emission Scanning Electron Microscopy (FE-SEM), ...
... We engineered a tiger nut residue (TNR, a low-cost agricultural waste material) through a facile and simple process to take advantage of the introduced functional groups (cetylpyridinium chloride, CPC) in the removal of 2,4-dichlorophenoxyacetic acid (2,4-D) in batch mode and further investigated its impingement on bacterial growth in a yeast-dextrose broth. The surface characterizations of the ad ...
Faisal I. Chowdhury; Jahidul Islam; A. K. Arof; M. U. Khandaker; Hossain M. Zabed; Ibrahim Khalil; M. Rezaur Rahman; Shahidul M. Islam; M. Razaul Karim; Jamal Uddin
... In this study, gel polymer electrolytes (GPEs) were prepared using polyacrylonitrile (PAN) polymer, ethylene carbonate (EC), propylene carbonate (PC) plasticizers and different compositions of tetrapropylammonium iodide (TPAI) salt. Linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) measurements were done using non-blocking Pt-electrode symmetric cells. The limiting cu ...
Hyeseung Chung; Zachary Lebens-Higgins; Baharak Sayahpour; Carlos Mejia; Antonin Grenier; Gabrielle E. Kamm; Yixuan Li; Ricky Huang; Louis F. J. Piper; Karena W. Chapman; Jean-Marie Doux; Ying Shirley Meng
... Cation-disordered rock salt materials have attracted much interest as high energy density cathode materials due to their anionic electrochemical activity, providing them extra capacity, along with their lower cost. They are, however, still the subject of numerous studies as they suffer from poor cyclability and relatively slow kinetics compared to traditional intercalation materials. In this work, ...
... The functionalized graphene oxide-ZnO (fGO/ZnO) nanoflower composites have been studied as a photocatalyst material for flow photodegradation of humic acid (HA) in real samples. The fGO/ZnO nanoflower was prepared via hydrothermal methods. The chemical and physical properties of the synthesized photocatalyst have been carried out by several techniques, including X-ray diffraction (XRD), scanning e ...
... LiNi₁–ₓ–yMnₓCoyO₂ (NMC) is an important class of high-energy-density cathode materials. The possibility of changing both x and y in the chemical formula provides numerous materials with diverse electrochemical and structural properties. It is highly desirable to have guidance on correlating NMC structural and electrochemical properties with their chemical composition for material designing and scr ...
Raman spectroscopy; X-ray diffraction; camouflage; cations; chemical reactions; cooling; electric potential difference; graphene; ionic liquids
Abstract:
... Multilayer graphene has been employed as a functional material for tuning the emissivity in mid- and long-infrared range, which shows great potential for various applications, such as radiative cooling and thermal camouflage. However, the stability of the multilayer graphene is not sufficient for practical applications yet. Even though it is reported that the integrity of the multilayer graphene i ...
Tim W. J. van de Goor; Yun Liu; Sascha Feldmann; Sean A. Bourelle; Timo Neumann; Thomas Winkler; Nicola D. Kelly; Cheng Liu; Michael A. Jones; Steffen P. Emge; Richard H. Friend; Bartomeu Monserrat; Felix Deschler; Siân E. Dutton
... Band gap tuning of hybrid metal–halide perovskites by halide substitution holds promise for tailored light absorption in tandem solar cells and emission in light-emitting diodes. However, the impact of halide substitution on the crystal structure and the fundamental mechanism of photo-induced halide segregation remain open questions. Here, using a combination of temperature-dependent X-ray diffrac ...
... The interactions between metal ions and graphene oxide (GO) nanosheets were investigated by in situ two-dimensional grazing incidence X-ray diffraction (GIXRD). We found that metal cations (Mn²⁺, Co²⁺, Cu²⁺, Fe³⁺) and GO can self-assemble into a hydroxide/GO superlattice by drop-casting a metal chloride and GO solution due to the electrostatic interactions between the positively charged hydroxide ...
... The development of more sustainable societies has become an urgent goal worldwide. Electrical batteries are currently seen as one of the most important energy storage technologies for the development of decarbonized societies. However, many lithium-ion battery manufacturers currently utilize cobalt, a toxic and hazardous mineral, in their batteries. Lithium-deficient manganese nickel oxide spinels ...
... Three anionic metal–organic frameworks (MOFs) {[Zn₃(BTEC)₂(H₂O)(4-BCBPY)]·(H₂O)}ₙ (1–3) (BTEC⁴⁻ = 1,2,4,5-benzenetetracarboxylic acid anion, 4-BCBPY²⁺ = 1,1′-bis(4-cyanobenzyl)-4,4′-bipyridinium dication) were synthesized in the reaction of 1,2,4,5-benzenetetracarboxylic acid with different metal salts such as ZnNO₃, ZnCl₂, and ZnSO₄, under solvothermal conditions in the presence of 1,1′-bis(4-cya ...
... The properties of metal/dioxygen species, which are key intermediates in oxidation catalysis, can be modulated by interaction with redox-inactive Lewis acids, but structural information about these adducts is scarce. Here we demonstrate that even mildly Lewis acidic alkali metal ions, which are typically viewed as innocent “spectators”, bind strongly to a reactive cis-peroxo dicopper(II) intermedi ...
... Recent work has demonstrated a low-temperature route to fabricating mixed ionic/electronic conducting (MIEC) thin films with enhanced oxygen exchange kinetics by crystallizing amorphous-grown thin films under mild temperatures, eluding conditions for deleterious A-site cation surface segregation. Yet, the complex, multiscale chemical and structural changes during MIEC crystallization and their imp ...
... Two lanthanide-containing porous coordination polymers, [Ln₂(bpdc)₆(phen)₂]·nH₂O (1) and [Ln₂(bpdc)₆(terpy)₂]·3H₂O (2) (Ln = Pr, Nd, or Sm–Dy; bpdc: 2,2′-bipyridine-5,5′-dicarboxylic acid; phen: 1,10-phenanthroline; and terpy: 2,2′:6′,2″-terpyridine), have been hydrothermally synthesized and structurally characterized by powder and single-crystal X-ray diffraction. Crystallographic analyses reveal ...
X-ray diffraction; ambient temperature; cations; color; energy transfer; nanocrystals; photoluminescence
Abstract:
... The tunable dual-color emitting Mn²⁺ doped CsPbCl₃₋ₓBrₓ nanocrystals (NCs) with near-unity photoluminescence quantum yield (PL QY) were synthesized through post-treatment of metal bromide at room temperature for fabrication of efficient warm white light-emitting diodes (WLEDs). Especially, the CdBr₂ treated blue-orange emitting Mn doped NCs with various Mn/Pb molar feed ratios exhibit higher PL QY ...
Thuat Nguyen-Tran; Van An Dinh; Nam Van Ly; Huu Duc Luong; Dung Thi Pham; Tu Thanh Truong; Hung Quoc Nguyen; Quang-Duy Dao; Chi Thi Kim Tran; Hien Thi Thu Bui; Duyen Thi Nguyen; My Nguyen Ha Dang; Van Vu Thi Phan; Quang Duc Truong
X-ray diffraction; absorption; cations; crystal structure; density functional theory; films (materials); guanidinium; iodides; lead; momentum; photoluminescence
Abstract:
... In this work, a new crystalline structure of two-dimensional (2D) Ruddlesden–Popper guanidinium lead iodide [C(NH₂)₃]₂PbI₄ with a particular organic cation orientation is proposed. Density functional theory calculations indicate that this structure of [C(NH₂)₃]₂PbI₄ is more energetically stable than the reported structure belonging to the Pmna space group. The crystalline and electronic structures ...
... The iodido bismuthates [Bi(18-crown-6)I₂][BiI₄] (1) and [Bi(18-crown-6)I₂][Bi₃I₁₀] (2), the neutral complex [Bi(C₆H₁₄O₄)I₃](18-crown-6) (3) as well as the polyiodides [Bi(18-crown-6)I₂][I₅](18-crown-6) (4), [Bi(18-crown-6)I₂]₂[I₁₄] (5) and [Bi(18-crown-6)I₂]₂[I₁₉] (6) were prepared by reaction of BiI₃, 18-crown-6, and I₂ at T = 60–120 °C. The compounds 1–5 were prepared in [n-Bu₃MeN][N(Tf)₂] as an ...
... LiNi₀.₅Mn₁.₅O₄ (LNMO) based spinel cathode materials for lithium-ion batteries are promising alternatives to widely used mixed transition-metal layered Li(Ni,Co,Mn)O₂ (NCM) oxides. LNMO is cobalt free and thus cost efficient, while providing a high operating voltage of 4.7 V (vs. Li/Li⁺) and remarkable energy density of ∼650 W h kg⁻¹. Commercialization and large-scale application however are still ...
X-ray diffraction; activated carbon; anodes; batteries; cathodes; cations; density functional theory; electric potential difference; hysteresis
Abstract:
... A promising high-voltage spinel oxide cathode material MgCrMnO₄ with 18% Mg/Mn inversion was synthesized successfully. A new custom operando battery device was designed to study the cation migration mechanisms of the MgCrMnO₄ cathode using 0.1 M Mg(TPFA)₂ electrolyte dissolved in triglyme and activated carbon as the anode. For the first time in multivalent batteries, high-quality operando diffract ...
... The crystal structure and associated property changes brought about by substituting Cu²⁺ and Cr³⁺ ions for Li⁺ and Ga³⁺ ions, respectively, in ordered LiGa₅O₈ are probed in the present work. The samples were synthesized by a single-step calcination process of epoxide-mediated xerogels rapidly and characterized extensively. Powder X-ray diffraction patterns revealed the preservation of the superstr ...
... Oxygen availability, an important property of cerium oxide catalysts, has been investigated over a wide range of concentrations for the substitutional solid solution ZnₓCe₁–ₓO₂ in nanocrystalline (∼2.5 nm) form. X-ray diffraction data of the as-synthesized materials indicates ZnₓCe₁–ₓO₂ to be a single-phase system up to approximately x = 0.16, with the lattice parameter decreasing linearly with zi ...
Fenghua Ding; Nenian Charles; Jaye K. Harada; Christos D. Malliakas; Chi Zhang; Roberto dos Reis; Kent J. Griffith; Matthew L. Nisbet; Weiguo Zhang; P. Shiv Halasyamani; Vinayak P. Dravid; James M. Rondinelli; Kenneth R. Poeppelmeier
... Elpasolite- and cryolite-type oxyfluorides can be regarded as superstructures of perovskite and exhibit structural diversity. While maintaining a similar structural topology with the prototype structures, changes in the size, electronegativity, and charge of cation and/or anion inevitably lead to structural evolution. Therefore, the nominal one-to-one relation suggested by a doubled formula of per ...
... We synthesize three perylene bisimide-based triads with donor–acceptor–acceptor (D∼A₁–A₂) architectures, in which the distance between D and A₁ is varied to study its influence on the excited state electron processes. Very different intramolecular charge transfer (D⁺∼A₁–A₂–) lifetimes in dichloromethane (DCM) for these three triads are revealed by steady-state and transient spectroscopies. Free-en ...
Igor Vorona; Volodymyr Dzhagan; Valentyna Nosenko; Serhiy Kondratenko; Oleksandr Selyshchev; Mykhailo Valakh; Serhiy Okulov; Nazar Mazur; Oleksandra Raievska; Oleksandr L. Stroyuk; Dietrich R. T. Zahn
Raman spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; ambient temperature; cations; chemical composition; copper; copper zinc tin sulfide; crystal structure; electron paramagnetic resonance spectroscopy; nanocrystals; stoichiometry; tin; zinc
Abstract:
... We report on electron paramagnetic resonance (EPR) spectroscopy of Cu–Zn–Sn–S (CZTS) nanocrystals (NCs) synthesized by a colloidal chemistry method. The chemical composition of the NCs is characterized by a strong deficit of tin and slight zinc enrichment with respect to the “ideal” stoichiometry of kesterite Cu₂ZnSnS₄. Nevertheless, X-ray photoemission spectroscopy (XPS) shows that the net cation ...
Anni I. Taponen; Awatef Ayadi; Manu K. Lahtinen; Itziar Oyarzabal; Sébastien Bonhommeau; Mathieu Rouzières; Corine Mathonière; Heikki M. Tuononen; Rodolphe Clérac; Aaron Mailman
... Cocrystallization of 7,7′,8,8′-tetracyanoquinodimethane radical anion (TCNQ–•) and 3-methylpyridinium-1,2,3,5-dithiadiazolyl radical cation (3-MepyDTDA⁺•) afforded isostructural acetonitrile (MeCN) or propionitrile (EtCN) solvates containing cofacial π dimers of homologous components. Loss of lattice solvent from the diamagnetic solvates above 366 K affords a high-temperature paramagnetic phase co ...
X-ray diffraction; cations; ferrimagnetic materials; oxidation; polymers; van der Waals forces
Abstract:
... The monoradical cation 1˙⁺ and anion 1˙⁻ based on tetracene were generated by one-electron oxidation and one-electron reduction of the bulky tetracene (1), respectively, which contain the largest π-fused skeletons reported to date. For monoradical species, 1˙⁺ and 1˙⁻, EPR spectra and DFT calculation results indicate the spin density delocalized over the whole molecules. Notably, in the solid stat ...
... The reaction of Bi and BiCl₃ with RbCl or CsCl in the Lewis-acidic ionic liquid (IL) [BMIm]Cl·4AlCl₃ at T = 200 °C yielded air-sensitive, shiny black crystals. X-ray diffraction on single crystals revealed the hexagonal structures of two new salts (Bi₈)M[AlCl₄]₃ (M = Rb, Cs), which are isostructural to the high-temperature form of (Bi₈)Tl[AlCl₄]₃. The known (Bi₈)²⁺ polycation is a square antiprism ...
Elias Sebti; Hayden A. Evans; Hengning Chen; Peter M. Richardson; Kelly M. White; Raynald Giovine; Krishna Prasad Koirala; Yaobin Xu; Eliovardo Gonzalez-Correa; Chongmin Wang; Craig M. Brown; Anthony K. Cheetham; Pieremanuele Canepa; Raphaële J. Clément
X-ray diffraction; cations; density functional theory; dielectric spectroscopy; electric vehicles; electronics; energy; heat; neutron diffraction; nuclear magnetic resonance spectroscopy; temperature; transmission electron microscopy
Abstract:
... In the pursuit of urgently needed, energy dense solid-state batteries for electric vehicle and portable electronics applications, halide solid electrolytes offer a promising path forward with exceptional compatibility against high-voltage oxide electrodes, tunable ionic conductivities, and facile processing. For this family of compounds, synthesis protocols strongly affect cation site disorder and ...
Zoha H. Syed; Mohammad Rasel Mian; Roshan Patel; Haomiao Xie; Zihan Pengmei; Zhihengyu Chen; Florencia A. Son; Timothy A. Goetjen; Alon Chapovetsky; Kira M. Fahy; Fanrui Sha; Xingjie Wang; Selim Alayoglu; David M. Kaphan; Karena W. Chapman; Matthew Neurock; Laura Gagliardi; Massimiliano Delferro; Omar K. Farha
... Understanding heterogeneous catalysts is a challenging pursuit due to surface site nonuniformity and aperiodicity in traditionally used materials. One example is sulfated metal oxides, which function as highly active catalysts and as supports for organometallic complexes. These applications are due to traits such as acidity, ability to act as a weakly coordinating ligand, and aptitude for promotin ...
... We report the results of a multi-technique study on the thermodynamics and kinetics of formamidinium lead iodide (FAPI) thermal decomposition. Thermodynamics was investigated by means of Knudsen effusion techniques. Kinetics was studied either by temperature-controlled powder X-ray diffraction or by two isoconversional treatments of differential scanning calorimetry data. FAPI appears to be much m ...
Eugenia S. Vasileiadou; Xinyi Jiang; Mikaël Kepenekian; Jacky Even; Michael C. De Siena; Vladislav V. Klepov; Daniel Friedrich; Ioannis Spanopoulos; Qing Tu; Imra S. Tajuddin; Emily A. Weiss; Mercouri G. Kanatzidis
... The nature of the organic cation in two-dimensional (2D) hybrid lead iodide perovskites tailors the structural and technological features of the resultant material. Herein, we present three new homologous series of (100) lead iodide perovskites with the organic cations allylammonium (AA) containing an unsaturated C═C group and iodopropylammonium (IdPA) containing iodine on the organic chain: (AA)₂ ...
... We examined the uptake of Tl(I) by two hexagonal birnessites and related phase transformations in laboratory experiments over 12 sequential additions of 0.01 M Tl(I)/Mn at pH 4.0, 6.0, and 8.0. The Tl-reacted Mn oxides were characterized for their structure, Tl binding, and morphology using X-ray diffraction, X-ray photoelectron and X-ray absorption spectroscopies, and transmission electron micros ...
... The synthesis of high entropy oxide (HEO) nanoparticles (NPs) possesses many challenges in terms of process complexity and cost, scalability, tailoring nanoparticle morphology, and rapid synthesis. Herein, we report the synthesis of novel single-phase solid solution (Mn, Fe, Ni, Cu, Zn)₃(O)₄ quinary HEO NPs produced by a flame spray pyrolysis route. The aberration-corrected scanning transmission e ...
Mana Ayari; Ali Banitalebi Dehkordi; Ghodsi Mohammadi Ziarani; Jahan B. Ghasemi; Mohammad Reza Ganjali; Meisam Soleimani; Alireza Badiei; Elena Niculina Dragoi; Hassan Rokni
... In this work, europium ion was doped into boron phosphate nanoparticles (BPO₄) using an ultrasonic method followed by the calcination process. The nanoparticles were characterized by various techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy, transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FT-IR), ...
... The exploration of new highly efficient and durable for the oxidation of amines to imines has gained immense attention. In this work, a new polyoxometalate-based metal–organic framework (POMOF) {Cu₄(C₂₆H₁₆N₄O₄)₄(CH₃CN)₂[SiW₁₂O₄₀]}·4H₂O (SiW-Cu-DPNDI) was constructed with a catalytic oxidant Keggin-type [SiW₁₂O₄₀]⁴⁻ anion, a photosensitizer N,N'-bis(4-pyridylmethyl)naphthalene diimide (DPNDI) ligan ...
Gaspar Darin; Kengo Imakuma; Rafael Trautwein Santiago; Klebson Lucenildo Da Silva; Luiz Fernardo Cótica; Martin Fabián; Jan Valíček; Horst Hahn; Vladimír Šepelák
... The datasets presented here are related to the research paper entitled “Disordered Gd₆UO₁₂₋δwith the cation antisite defects prepared by a combined mechanochemical−thermal method”[1]. The datasets complement the findings [1] on the effect of the combined mechanochemical−thermal processing of the stoichiometric mixture of solid precursors (3Gd₂O₃ + UO₂) on the formation of Gd₆UO₁₂₋δ phase. In this ...
... A new salt (CH₆N₃)[t-Cr(C₂O₄)₂(H₂O)₂]·2H₂O (1) (CH₆N₃⁺ = guanidinium cation) has been synthesized and characterized by single-crystal X-ray diffraction, FT-IR and UV–Vis spectroscopies, elemental and thermogravimetric analyses. In the crystal structure of 1, the chromate(III) ion lies on an inversion center in the form of an elongated octahedron. The coordination sphere consists of four oxygen ato ...
... Dual graphite batteries (DGBs) employ graphite as an intercalation host and store energy using the redox reactions of ionic liquid electrolyte-derived ions with graphite electrodes. As bulky (e.g., imidazolium-based) cation intercalation into the negative graphite electrode may cause its deterioration and thus aggravate self-discharge behaviour, a deep mechanistic understanding of such intercalati ...
... Since adsorption on clay minerals is one of the most popular water-pollutant removal method, it is important to consider the coexistence of several compounds that can affect pollutant retention. In this work, the competitive behaviour between cationic herbicide paraquat (PQ) and a benzalkonium chloride compound (BAC) on montmorillonite (MMT) was performed by adsorption experiments and analysed by ...
... Adsorption behavior of lutetium by hydroxyapatite (HAP) was investigated by considering pH, adsorbent dose, contact time, initial concentration of lutetium, and temperature. The adsorbent was synthesized and characterized by X-ray diffraction (XRD; JCPDS file 01–04-3708), and the point of zero charge was 7.22. When the initial pH (pHᵢ) was 3, the final pH (pHf) of the system was approximately 6, a ...
... Ionic liquids (ILs (1-butyl-3-methylimidazolium chloride ([C₄mim][Cl]) and 1-butyl-3-methylimidazolium tetrafluoroborate ([C₄mim][BF₄]))) were used as heat transfer fluids for solar thermal collectors. The additive of ILs was biochar containing copper and silver nanoparticles (Cu–Ag/biochar) to improve the adsorption of solar irradiation and thermal conductivities. After impregnation and reduction ...
... There is currently significant interest in adsorbents for selective removal of caffeine from water. Here, we examined caffeine adsorption in a natural montmorillonite (Mnt) smectite clay mineral. A simple exchange of the original monovalent sodium interlayer cations with polyvalent aluminum cations increased the caffeine adsorption rate of the smectite by approximately 1.6 times (maximum adsorptio ...
... This research demonstrates the cation and anion transfer of an organic ionic plastic crystal (OIPC), quinuclidinium hexafluorophosphate ([HQ]PF₆), in the pure state and mixtures doped with lithium or chloride ions. The pure material and the mixtures show relatively simple thermal behaviors. Powder X-ray diffraction determined a cubic crystal structure, a common feature of OIPCs, in the high-temper ...
X-ray diffraction; benzaldehyde; byproducts; carbon-hydrogen bond activation; catalytic activity; cations; chemical bonding; hydrides; hydrogen; ligands; moieties; nickel; nuclear magnetic resonance spectroscopy; reducing agents; titration
Abstract:
... Nickel(I) metalloradicals bear great potential for the reductive activation of challenging substrates but are often too unstable to be isolated. Similar chemistry may be enabled by nickel(II) hydrides that store the reducing equivalents in hydride bonds and reductively eliminate H₂ upon substrate binding. Here we present a pyrazolate-based bis(β-diketiminato) ligand [Lᴾʰ]³– with bulky m-terphenyl ...
... To expand the application range of herbicidal ionic liquids (HILs), we attempted to increase the amount of the systemic herbicide dicamba in its HILs through the formation of neither purely ionic nor neutral hydrogen-bonded complexes (so-called oligomeric ions) of parent acid and conjugate base. We realized we faced an important question—how far is it possible to increase the amount of active spec ...
... Herein, the size dependent behavior of cobalt ferrite nanoparticles was investigated using synchrotron radiation based techniques. Scanning electron micrographs revealed the enhancement of particle/crystallite size with increase of annealing temperature. Moreover, the shape of these particles also changed with increase of crystallite size. Saturation magnetization increased with increase of crysta ...
Palmerina González-Izquierdo; Oscar Fabelo; Garikoitz Beobide; Israel Cano; Idoia Ruiz de Larramendi; Oriol Vallcorba; Jesús Rodríguez Fernández; María Teresa Fernández-Díaz; Imanol de Pedro
... A novel imidazolium halometallate molten salt with formula (trimim)[FeCl₄] (trimim: 1,2,3-trimethylimidazolium) was synthetized and studied with structural and physico-chemical characterization. Variable-temperature synchrotron X-ray powder diffraction (SXPD) from 100 to 400 K revealed two structural transitions at 200 and 300 K. Three different crystal structures were determined combining single ...
X-ray diffraction; X-ray photoelectron spectroscopy; cations; cesium; electrodes; gases; lead; models; scanning electron microscopy; silver; solar cells; ultraviolet-visible spectroscopy
Abstract:
... Lead halide perovskite solar cells have significantly increased in both efficiency and stability over the last decade. An important aspect of their long-term stability is the reaction between the perovskite and other materials in the solar cell. This includes the contact materials and their degradation if they can potentially come into contact through, e.g., pinholes or material diffusion and migr ...
... We present a combined experimental and computational study of the effect of charge doping in the osmium based double perovskite Ba₂Na₁–ₓCaₓOsO₆ for 0 ≤ x ≤ 1 in order to provide a structural and electronic basis for understanding this complex Dirac–Mott insulator material. Specifically, we investigate the effects of the substitution of monovalent Na with divalent Ca, a form of charge doping or all ...
... Ca₅Mg₄₊ₓV₆O₂₄ (− 0.05 ≤ x ≤ 0.15) ceramics were prepared via a conventional solid-state reaction route. XRD patterns and Raman spectra confirmed that a single garnet phase was formed in all samples. The full-width-at-half maximum of Raman peaks revealed that an appropriate excess of magnesium ions improves the ordering degree of cations and quality factor (Q × f) value. The dielectric constant (εᵣ ...
... In this study, various concentrations of the large-sized cation iodide, namely, phenylethylammonium iodide (PEAI), incorporated in lead iodide (PbI₂) solid films react with heated methylammonium iodide (MAI) to fabricate 2D/3D mixed perovskite films with vertical phase distribution, which are prepared by the low-pressure vapor-assisted solution process (LP-VASP). The 2D/3D mixed perovskite films e ...
... The expansive clay soils, which cover most of the new urbanized areas in Egypt, create major damages in most of the engineering structures and infrastructures such as buildings, roads, bridges, pipelines and others due to bad human activities, e.g. lack of maintenance for sewage and drinking lines, and flood irrigation of golf areas which causes fluctuation of water content through the foundation ...
X-ray diffraction; cathodes; cations; chemical structure; combustion; commercialization; crystallites; electrochemistry; energy; energy density; markets
Abstract:
... In order to satisfy the energy demands of the electromobility market, further improvements in cathode materials are receiving much attention, especially high energy density cathode materials for Li-ion batteries (LIBs). In this work, the self-propagating combustion (SPC) method is use to synthesise undoped LiNi₀.₆Co₀.₃Ti₀.₁O₂ (LNCT), novel nano-sized Al-doped LiNi₀.₆Co₀.₃₋ₓAlₓTi₀.₁O₂ (LCA) and LiN ...
... In this study, the effects of the new biodegradable chelating ligands, i.e., methylglycinediacetic acid (MGDA) and L-glutamic acid-N,N-diacetic acid (GLDA), were compared with that of ethylenediaminetetraacetic acid (EDTA) on lead (Pb) sorption by montmorillonite (MMT) at equimolar Pb:ligand ratios. The results of PHREEQC simulations indicated that Pb was predominantly present in the form of negat ...
Jannis Thien; Jascha Bahlmann; Andreas Alexander; Martin Hoppe; Tobias Pohlmann; Kevin Ruwisch; Carola Meyer; Florian Bertram; Karsten Küpper; Joachim Wollschläger
... In order to explore an alternative pathway to prepare ultrathin CoFe₂O₄ films, epitaxial CoO/Fe₃O₄ bilayers with varying film thickness of the CoO film were grown on Nb-doped SrTiO₃(001) substrates via reactive molecular beam epitaxy. Thereafter, cobalt ferrite films with varying stoichiometry were prepared by post-deposition annealing at different temperatures. The thermally mediated interdiffusi ...
... Understanding electrochemical behavior of the alkaline metal cation–graphene interface in electrolyte is essential for understanding the fundamental electrochemical interface and development of graphene-based technologies. However, most studies have been mainly conducted based on typical electrochemical analysis and computational evaluation, and the fundamental properties of both cations and graph ...
João Paulo de Campos da Costa; Marcelo Assis; Vinícius Teodoro; Andre Rodrigues; Camila Cristina de Foggi; Miguel Angel San-Miguel; João Paulo Pereira do Carmo; Juan Andrés; Elson Longo
... This study demonstrates that the electron beam irradiation of materials, typically used in characterization measurements, could be employed for advanced fabrication, modification, and functionalization of composites. We developed irradiation equipment using an electron beam irradiation source to be applied in materials modification. Using this equipment, the formation of a thick Ag film on the Ag₃ ...
... Acid mine drainage (AMD) is characterized by low pH, high soluble Fe, and heavy metal concentrations. Conventional lime neutralization produces large amounts of Fe(OH)₂ and Fe(OH)₃, which complicate subsequent disposal. Secondary iron minerals synthesized by biomineralization can reduce the concentration of soluble Fe in addition to adsorbing and removing heavy metals in AMD. Therefore, an appropr ...
... A series of promising Ce–Co–Fe catalysts were successfully synthesized using a cetyl-trimethylammonium-bromide-assisted co-precipitation method and investigated for diesel soot combustion. The surface morphological and structural properties were systematically examined using various techniques: X-ray diffraction, scanning electron microscope, N₂ adsorption–desorption, Raman spectroscopy, temperatu ...
... The H₂S removal performances of four deep eutectic solvent (DES) based nanofluid (NF) systems were measured using dynamic absorption experiment. The Cu containing NF system is found to be an excellent absorbent for H₂S removal with a significantly enhanced desulfurization performance compared with DES original solution. Besides, the NF systems have relatively high regeneration performance. The NF ...
X-ray diffraction; cathodes; cations; commercialization; dielectric spectroscopy; dissociation; electric potential difference; mixing; temperature
Abstract:
... Ni-rich cathode materials have attracted wide attention on account of their high specific capacity. However, the poor cycle retention of Ni-rich cathode materials, especially at high voltage or high temperature, is recognized as the main obstacle for extensive commercialization. In this research, we propose a new strategy of doping NCM622 (LiNi₀.₆Co₀.₂Mn₀.₂O₂) with Ta⁵⁺ to improve the structural s ...
... In order to overcome the toxicity and long-term stability of hybrid organic/inorganic Pb-based halide perovskites, which are believed to be the key obstacles for their utilization in optoelectronic devices, herein we explored the synthesis of binary Pb–Sn perovskite nanocrystals (NCs) with fixed composition of methylammonium (MA) and cesium (Cs) cations. Mixed MA-Cs composition has been used to ac ...
... The Basil seeds mucilaginous polysaccharide exhibits remarkable physical and chemical properties like high water-absorbing capacity, emulsifying, and stabilizing properties. The metal-organic frameworks are one of the most promising precursors made of metal clusters and organic connectors for the fabrication of advanced adsorbents due to their unique properties. In this study, the bionanocomposite ...
... In order to effectively remove reactive brilliant red (RBR) in aqueous solution, a novel Cu(II) coordinated chitosan-based magnetic composite (CTS-Cu@SiO₂@Fe₃O₄) was prepared. The physicochemical properties of the resultant adsorbent were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), vibrating sample magnetometer (VSM) thermogravimetric (TG) analysis, sc ...
X-ray diffraction; cations; cesium radioisotopes; comparative study; decontamination; foams; freshwater; ion exchange; liquid wastes; liquids; polymers; porous media; potassium; radioactive waste; scanning electron microscopy; sodium; sorption isotherms; transmission electron microscopy
Abstract:
... Geopolymer foam hosting a 3D network of interconnected pores was synthetized and functionalized with a potassium copper hexacyanoferrate [K₂CuFe(CN)₆] in order to decontaminate radioactive liquid waste containing cesium. The Geopolymer Foam (GF) and Functionalized Geopolymer Foams (FGF) were characterized using a panel of characterization techniques (SEM, TEM, XRD …) before studying their capacity ...