A set of organoantimony(III/V) and organobismuth(V) fluorides (i.e. L SbF2, L SbClF, LPh2SbF2, L SbF4 and LPh2BiF2) bearing the 2-{[(2,6-diisopropylphenyl)imino]methyl}phenyl-as a C,N-chelating ligand (L) has been prepared using LCNR2SnF (where LCN = 2-( N,N-dimethylaminomethyl)phenyl); R = n-Bu or Ph) and/or XeF2 as fluorinating agents. All species were characterised by the combination of elemental analy-sis and multinuclear solution NMR spectroscopy. Solid-state structures of all complexes were established by the sc-XRD analysis. In addition, theoretical calculations were carried out to corroborate the experi-mental results. Preparation and structural characterisation of LSbI2 is also reported.(c) 2023 Elsevier B.V. All rights reserved.

The effect of ionic liquids on the separation of chlorinated anionic dyes such as Mordant Blue 9 (MB9) or Acid Yellow 17 (AY17) via ion exchange has been investigated in model aqueous solutions that simulate wastewater from the textile dyeing industry. The effect of ionic liquids chemical nature on the separation efficiency of mentioned dyes has been compared. It was found that especially ionic liquid based on quaternary ammonium salts comprising two or three long alkyl chains bound to the quaternary ammonium nitrogen (typically benzalkonium chloride or Aliquat 336) are very effective for the separation of both studied MB9 and AY17 from aqueous solution. In addition, the innovative technique has been developed for the reactivation of spent ionic liquids which is based on the chemical reduction of the formed ion pairs using NaBH4/NiSO4, NaBH4/Na2S2O5 or Raney Al-Ni alloy/NaOH. Thus, only NaBH4/NiSO4 in co-action with Al-Ni alloy enables both effective reduction of the azo bond and subsequent hydrodechlorination of emerging chlorinated aromatic amines. The efficiency of tested dyes separation or regeneration of ion pairs was evaluated by determination of the absorbance at wavelength of the maximum absorbance, of the Chemical Oxidation Demand (COD), and of the Adsorbables Organically bound Halogens (AOX). The formation of ion pairs or products of reduction and hydrodechlorination of these ion pairs has been studied using the 1H NMR and LC-MS techniques.

Raney Al-Ni contains 62% of Ni2Al3 and 38% NiAl3 crystalline phases. Its applicability has been studied within an effective hydrodehalogenation of hardly biodegradable anti-inflammatory drug diclofenac in model aqueous concentrates and, subsequently, even in real hospital wastewater with the aim of transforming them into easily biodegradable products. In model aqueous solution, complete hydrodechlorination of 2 mM aqueous diclofenac solution (0.59 g L−1) yielding the 2-anilinophenylacetate was achieved in less than 50 min at room temperature and ambient pressure using only 9.7 g L−1 of KOH and 1.65 g L−1 of Raney Al-Ni alloy. The dissolving of Al during the hydrodehalogenation process is accompanied by complete consumption of NiAl3 crystalline phase and partial depletion of Ni2Al3. A comparison of the hydrodehalogenation ability of a mixture of diclofenac and other widely used halogenated aromatic or heterocyclic biocides in model aqueous solution using Al-Ni was performed to verify the high hydrodehalogenation activity for each of the used halogenated contaminants. Remarkably, the robustness of Al-Ni-based hydrodehalogenation was demonstrated even for the removal of non-biodegradable diclofenac in real hospital wastewater with high chloride and nitrate content. After removal of the insoluble part of the Al-Ni for subsequent hydrometallurgical recycling, the low quantity of residual Ni was removed together with insoluble Al(OH)3 obtained after neutralization of aqueous filtrate by filtration.

A tunable approach for the non-phosphine synthesis of monodisperse, highly photoluminescent ZnSexS1-x and Mn-doped ZnSe0.1S0.9 quantum dots (QDs) using (Z)-1-(octadec-9-enyl)-3-phenylselenourea and (Z)-1-(octadec9-enyl)-3-phenylthiourea as novel sources of selenium and sulphur is provided. QDs syntheses were performed in an organic disperse medium at 280 degrees C using environmentally friendly and at the same time highly reactive N,N'disubstituted thio- and selenoureas.By varying the molar ratios of sulphur and selenium sources, ZnSexS1-x QDs, where x445; = 0.05, 0.1, 0.15, 0.2, 0.3, 0.4, 0.5, and 0.75, were obtained. Mn-doped ZnSe0.1S0.9 QDs (0.5-15 molar %) have been synthesized by the low cost hot-injection method. The presence of manganese in ZnSe0.1S0.9 QDs resulted in the appearance of the expected second emission band (579 nm), the maximum intensity of which was determined for Mn(5%):ZnSe0.1S0.9 QDs. According to the analytical data, ZnSexS1-x and Mn-doped ZnSe0.1S0.9 QDs are consistent with the desired elemental composition and uniform in size. The chemical composition, morphology and crystal structure of prepared undoped ZnSexS1-x and Mn-doped ZnSe0.1S0.9 QDs were studied by X-Ray diffraction (XRD), energy dispersive X-Ray spectroscopy (EDS), X-Ray photoelectron spectroscopy (XPS), scanning transmission electron microscopy (STEM) and transmission electron microscopy (TEM) analyses. The optical properties of nanocomposite materials based on synthesized ZnSexS1-x and Mn-doped ZnSe0.1S0.9 QDs in a polymer matrix of polyvinyl toluene (PVT) were also studied. It should be noted that transparent monoliths have the same photoluminescent characteristics as QDs. These results give proof of the chemical stability of the resulting nanomaterials and can contribute to their possible transfer in the photodetectors and LEDs production.

Solid solution AgInS2-ZnS nanostructures were prepared by reacting (Z)-1- (octadec-9-enyl)-3-phenylthiourea and 1-dodecanethiol with the corresponding metal linoleates. The combination of sulfur sources in modified ratios, which individually do not lead to significant results, resulted in the successful formation of nanorod-shaped heterostructures. The effect of sulfur source ratios on the structure, morphology, and optical properties of yellow-red emitting nanocrystals was systematically studied by X-ray diffraction (XRD), energy dispersive X-ray analysis (EDS), X-ray photoelectron spectroscopy (XPS) and scanning transmission electron microscopy (STEM) analyzes. Nanocomposite materials based on polyvinyl toluene co-divinylbenzene (PVT-DVB) were investigated for each of the resulting nanostructures. It was demonstrated that even traces of nanomaterial (∼ 0.1 wt. %) provide a high photoluminescence quantum yield (PL QY up to 61.5%) of prepared nanocomposites.

Stannylenes of L2Sn type bearing either C,N-chelating (1, L = LCN = 2-(N,N-dimethylaminomethyl)phenyl) or bulky amido (2, L = LN = N(SiMe3)2) ligands react with cyanogen bromide (Br-C[triple bond, length as m-dash]N) via an oxidative-addition reaction to give monomeric six-coordinate (LCN)2Sn(Br)CN (1a) and four-coordinate (LN)2Sn(Br)CN (2a) stannanes in moderate yields. In solution, both 1a and 2a undergo instantaneous bromido-cyanido ligand redistribution reactions, leading to mixtures containing 1a, (LCN)2SnBr2 (1b) and (LCN)2Sn(CN)2 (1c) or 2a, (LN)2SnBr2 (2b) and (LN)2Sn(CN)2 (2c), respectively. The prepared species were characterised by multinuclear NMR spectroscopy in solution (1a-c and 2a-c) and in the solid state (1a-c). The crystal structures of 1a/b/c, 2a/b/c and sole 2b were determined by XRD analyses. DFT calculations and QTAIM analysis were also carried out to corroborate the experimental results.

The catalytic effect of copper in Devarda’s Al-Cu-Zn alloy (Dev. alloy) and sole metallic copper, copper salts and copper oxides in the coaction of NaBH4 within the hydrodehalogenation (HDH) of polybrominated phenols, such as the herbicide Bromoxynil in alkaline aqueous solution has been investigated. Namely, the hydrodebromination (HDB) activity of Dev. alloy/NaOH system has been compared to heterogeneous Cu-based catalysts using NaBH4 as a reductant. Differences in the solid-state structures of used Cu-based heterogeneous catalysts after the mentioned HDB process have been studied using the powder XRD and SEM techniques. It was found that some of the used copper-based catalysts are reusable and reasonably effective even at room temperature. Efficiency of the most promising copper-based reduction systems (Dev. alloy/NaOH and Cu-based catalysts/NaBH4) have been successfully tested within the HDB of industrially important brominated flame retardant tetrabromobisphenol A (TBBPA). Dev. alloy/NaOH and Cu-based catalyst generated in-situ within the CuSO4/NaBH4 produced were recognized as the most active HDB agents for complete debromination of both BRX and TBBPA.

The surface of any binary or multi-component nanocrystal has imperfections and defects. The number of surface defects depends both on the nature of the nanomaterial and on the method of its preparation. One of the possibilities to confine the number of surface defects is the epitaxial growth of the shell, which leads to a change in the physical properties while maintaining the morphology of the core. To form a shell of the desired thickness, an accurate calculation of the amount of its precursors is substantial to avoid the appearance of individual crystals consisting of the shell material. This study aimed to develop an effective calculation method for the theoretical amount of precursors required for the formation of a ZnS shell on the surface of a Cd0.25Zn0.75Se core, followed by the practical implementation of theoretical calculations and characterization of the prepared nanomaterials. This method allows the complete control of the masses and volumes of the initial reagents, which will in turn prevent undesirable nucleation of nuclei consisting of the shell material. In the synthesis of Cd0.25Zn0.75Se/ZnS core/shell quantum dots (QDs), the sources of chalcogens were substituted seleno- and thioureas, which are capable of not only supplanting modern toxic sources of sulfur and selenium but also allowing one to perform the controlled synthesis of highly photoluminescent QDs with a low number of surface defects. The result of this shell overcoating method was an impetuous augmentation in the photoluminescence quantum yield (PL QY up to 83%), uniformity in size and shape, and a high yield of nanomaterials. The developed synthetic technique of core/shell QDs provides a controlled growth of the shell on the core surface, which makes it possible to transfer this method to an industrial scale.

Invited for the cover of this issue is the group of Michal Straka and Martin Dračínský (IOCB Prague, Czech Academy of Sciences). The image depicts a neutron star, which is used to represent the relativistic effects between a heavy element and a hydrogen atom reported in this work. Read the full text of the article at 10.1002/chem.202001532 .

Semiconductor quantum dots (QDs) have attracted great attention due to their unique optical and chemical properties. An increasing demand for size and shape uniformity of QDs, high quantum yield (QY) and photochemical stability can be resolved by synthetic methods. Here we report a study of the effect of the precursor ratios within the synthesis of a series of Cd–Zn–S QDs. Trisubstituted thiourea (N-phenylmorpholine-4-carbothioamide) as a new and environmentally friendly source of sulphur in the synthesis of Cd0.2Zn0.8S QDs (Cd, Zn : S molar ratios = 1 : 0.5; 1 : 1; 1 : 1.5; 1 : 2; 1 : 2.5) and CdxZn1−xS QDs (where x = 0.1; 0.25; 0.5; 0.75; 0.9) has been investigated. It was determined that an increase in the molar ratio of trisubstituted thiourea to metals leads to the growth of QDs and as a consequence, to a small emission red shift in the visible region of the spectrum. However, no significant changes in the elemental ratio in the material were detected. It was found that with an excess of trisubstituted thiourea taken to the reaction, oleylamine (OAm) as a co-ligand replaces linoleic acid from the protective shell of the QDs. In the case of an increase of Cd content in the CdxZn1−xS QDs, a significant shift in the emission to the red region of the spectrum was observed with an increase in the size of the QDs while their shape was unchanged. Based on the XRD data, a gradual transition from a cubic to a hexagonal crystal structure was detected. The high quantum yield (70%), the narrow photoluminescence (PL) signal (FWHM < 31 nm) and the size uniformity of the obtained nanomaterials are promising features for production of highly sensitive sensors and LEDs.

Observation of through-space (or through-hydrogen bond) relativistic effects between a heavy element (iodine) and a hydrogen atom is reported in this work. The artwork represents a neutron star (an extremely heavy space object) that causes relativistic time effects (a connotation of Einstein's theory of relativity). A stylized spacecraft with the shape of our experimental molecule (dimethylaminopyridine) is approaching the neutron star and the interaction between its hydrogen atom and the neutron star appears. More information can be found in the Communication by M. Straka, M. Dračínský, et al. on page 8698.

Nucleation and growth of quantum dots (QDs) in solution are mainly controlled by the kinetic and thermal modes of the reaction process. By influencing any of them, the properties of the final nanocrystals can be tuned. The influences of temperature and chemical nature of starting materials on nucleation and, as a consequence, on the structure and optical properties of Cd0.15Zn0.85S QDs have been systematically investigated by one-pot and hot-injection methods. All reactions were performed in organic disperse medium using N,N'-disubstituted and N,N',N'-trisubstituted thioureas (TU) as a new sources of sulfur. In addition to environmental friendliness, each of them has a number of unique chemical properties. The effect of the substituents' nature in thioureas on the morphology, size and optical properties of synthesized QDs has been studied. The strong correlation between the metal ratios taken to the reaction and elemental analysis (EDS) results for all obtained Cd0.15Zn0.85S QDs was found. However, prepared nanomaterials have different size (2.9-4.6 nm) and morphology. The optical features have also changed under the various thermal conditions. Especially, the changes in the photoluminescence spectra of QDs synthesized with different thioureas are noticeable. Highly photoluminescent (photoluminescence quantum yield PL QY up to 67%), morphologically and structurally homogeneous blue-emitting Cd0.15Zn0.85S QDs were obtained. (C) 2019 Elsevier B.V. All rights reserved.

Despite a great number of studies devoted to the synthesis of chalcogenide quantum dots (QDs), many essential questions remain open up to date. Primarily, it is a safety of the synthesis, both in the laboratory and in the industry. Another issue is the reproducibility of QDs with desired characteristics. And, without doubt, the ability to adjust properties of the resulting QDs by the implementation of various approaches to the synthesis is significant. Here we provide a novel approach to the synthesis of ternary Cd-Zn-Se QDs (ratios Cd: Zn = 10 : 90; 25 : 75; 50 : 50; 75 : 25; 90 : 10) using disubstituted selenourea as a novel source of selenium. (Z)-1-hexyl-3-(octadec-9-enyl)selenourea was synthesized in three steps with a good yield of the final product. It opens up a simple, convenient and environmentally friendly way to the synthesis of the selected QDs. Varying the molar ratios of Cd and Zn, QDs of different composition were produced in high yields. According to the conducted research, highly photoluminescent ternary Cd-Zn-Se QDs (photoluminescent quantum yield PL QY up to 64%) are uniform, both in elemental composition and in size (3.6-5.3 nm). Moreover, the selection of given selenourea made it possible to scale the synthesis by 24 times with an increase in the amount of QDs without loss of product quality. This demonstrates the feasibility to produce such type of materials on an industrial scale.

Two new porous coordination polymers, [Co-3(mu(3)-OH)(Bcb10DC)(2.5)(DEF)(3)(EtOH)(1.5)(H2O)(0.5)] center dot DEF center dot EtOH (3b) and [Co-2(Bcb12DC)(2)(DMF)(4)(EtOH)] center dot 2EtOH (4) based on 10- and 12-vertex p-bicarboranedicarboxylic acids, 1,1'-bi-(1,10-dicarba-closo-decaborane)-10,10'-dicarboxylic acid (H(2)Bcb10DC) and 1,1'-bi-(1,12-dicarba-closo-decaborane)-12,12'-dicarboxylic acid (H(2)Bcb12DC) were synthesized. Their properties were compared with the two known analogues based on shorter ligand-homologues, [Co(cb10DC)(DMF)] (1) and [Co-4(OH)(2)(cb12DC)(3)(DMF)(2)(H2O)(4)] center dot 3DMF center dot EtOH (2). The structure of 3b is based on a trinuclear cluster and has a 3D structure with a 5-c bnn underlying net, while 4 is based on a binuclear cluster and composed of stacked 2D sql layers. Activated 3' with altered structure has S-BET(N-2) of 1012 m(2) g(-1) and 4' with mostly retained structure 920 m(2) g(-1). Gas adsorption by 3' and 4' at 1 bar is: 80.1 cm(3) g(-1) (0.72%(wt)) and 81.3 cm(3) g(-1) (0.73%(wt)) H-2 at 77 K; 16.7 and 21.9 cm(3) g(-1) CO2 at 273 K; 6.2 and 10.0 cm(3) g(-1) of CH4 at 273 K. The isosteric heat of adsorption Q(st) at zero coverage are respectively: 5.0 and 4.5 kJ mol(-1) for H-2, 16.7 and 21.9 for CO2; 6.2 and 10.0 for CH4. 2' with similar to 645 m(2) g(-1) (calc. 883 m(2) g(-1)) has the highest mass-specific H-2 adsorption, > 30% than other compounds, while Q(st) is close to 1' and slightly higher than for 3' and 4'. Adsorption of CO2 and CH4 and Q(st) are similar to 1.5-2 times lower for 3' and 4' compared to 1' and 2'. The surface area specific adsorption of H-2, CO2 and CH4 is the highest for 1'. The CO2/CH4 LAST selectivities (0.15/0.85; 1 bar, 298 K) are in 2-4.5 range. 3' and 4' retain a significant part of porosity after soaking in water unlike 1' and 2'.

NovelC,N-chelated organotin(iv) complexes bearing weakly coordinating carborane moieties were prepared and used as a catalyst precursor for the direct synthesis of dimethyl carbonate (DMC) from CO2and methanol.

Non-symmetric lithium nitriloamidinate complexes of composition 3- or 4-(N equivalent to C)C6H4[C(NSiMe3)(NAr)] Li(D)(n) where Ar is phenyl, 2,6-(CH3)(2)C6H3 (Dmp) or 2,6-[(CH3)(2)CH](2)C6H3 (Dipp); D means coordinated solvent - THF or diethylether and n = 1 or 2, were prepared from 1,3- or 1,4-dicyanobenzene and one molar equivalent of appropriate trimethylsilylated lithium amide. Disymmetric dilithium bisamidinate complexes of 1, 3- or 1, 4-{[(NSiMe3)(NAr)C]Li(D)(n)}(2)C6H4 type were prepared by the same procedure using two molar equivalents of lithium amides. When the isolated lithium nitriloamidinate complexes were reacted with lithium amide of another type, asymmetric dilithium bisamidinates 3- or 4-{[(NSi-Me-3)(NAr)C]Li(D)(n)}{[(NSi-Me-3)(NAr')C]Li(D)(n)}C6H4 were obtained and characterized. The reaction period for essentially quantitative conversion of the starting material to desired bisamidinates is strongly dependent on the substitution pattern of parent lithium amides as well as the dinitrile going from hours to more than forty days in the case of Dipp-substituted amide and 1,3-dicyanobenzene combination. In the solid state, complexes bearing less bulky substituent - phenyl - tend to aggregate to dinuclear species for lithium nitriloamidinates or linear polymers for bisamidinates. Presence of more sterically demanding substituents directed the structure of prepared compounds to mononuclear species with isobidentate bonding fashion of amidinates and two molecules of solvent being extra-coordinated to the lithium atom. For all lithium amidinates prepared, the central lithium atom has distorted tetrahedral coordination geometry with ligands being in an anisobidenate or bidentate-bridging bonding fashion. (C) 2017 Elsevier B.V. All rights reserved.

This paper presents a study of pnictogen bonding in a series of pyrazine•PnX 5 (Pn = P, As, Sb and X = F, Cl, Br) complexes. The whole series was studied computationally. Moreover, the pyrazine complexes with PCl 5 and SbCl 5 were prepared and characterized experimentally. It was found that the Pn-N distances are only slightly elongated when compared to the sum of covalent radii. The conformation of PnX 5 changed considerably upon the complex formation, which resulted in a significant change of the dipole moment of the PnX 5 fragment and a considerably more positive σ-hole on the pnictogen atom. Finally, interaction energies were decomposed in order to provide a deeper insight into the nature of the studied pnictogen-bonded complexes. Graphical abstract The conformation of PnX5 changed considerably upon the complex formation, which resulted in a considerably more positive σ-hole on the pnictogen atom.