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A direct mass spectrometry method utilizing reactive paper spray ionization was developed for sensitive cannabinoid quantitation in biofluid matrices. The ca. 2-minute sample measurements used on-paper derivatization to significantly increase paper spray mass spectrometry (PS-MS) positive ion mode sensitivity while minimizing sample preparation steps. Calibrations demonstrate high linearity, with R2 > 0.99 for (−)-trans-Δ9-tetrahydrocannabinol (THC) in oral fluid and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) in urine. The limit of detection and lower limit of quantitation were 0.78 and 10 ng mL−1 for THC in oral fluid and 1.3 and 10 ng mL−1 for THC-COOH in urine, respectively. THC-COOH levels measured by reactive PS-MS in seven spiked human urine samples showed bias of −9.4 to 5.9%, and percent difference values of −16.8 to 9.8% in comparison with a reference LC-MS method. Based upon the method simplicity, validation experiments, sensitivity, and rapidity, we conclude that reactive PS-MS has potential applications for rapid cannabinoid drug testing in urine and oral fluid. [ABSTRACT FROM AUTHOR]

Phosphates, whose obvious disadvantage is the relatively small birefringence, can be overcome by the introduction of post-transition metal cations containing stereochemically active lone-pair electrons. In this paper, two new compounds were successfully explored in the A–Sb–P–O system, i.e. Cs2Sb3O(PO4)3 (CsSbPO) and (NH4)2Sb4O2(H2O)(PO4)2[PO3(OH)]2 (NH4SbPOH). Transmission spectra show that CsSbPO has a surprising transmission range with a UV cutoff edge of 213 nm. First-principles calculations show that both compounds have a wide band gap (5.02 eV for CsSbPO and 5.30 eV for NH4SbPOH) and enlarged birefringence (Δn = 0.034@1064 nm for CsSbPO and Δn = 0.045@1064 nm for NH4SbPOH). The results of real-space atom-cutting investigations show that the distorted [SbOx] polyhedra originating from the asymmetric lone pair electrons give the main contribution to the total birefringence and overcome the disadvantage of small birefringence of phosphates but maintain wide transition windows. [ABSTRACT FROM AUTHOR]

In this work, we have reviewed non-covalent interactions in technetium hexahalide compounds and obtained eight new compounds of the CatnTcHal6 type, where Cat = dimethylammonium, tetramethylammonium, caffeinium, benzothiazolium, nicotinamidium, and pyrazolium, and Hal = Cl, Br. SCXRD studies were carried out for new compounds. In some compounds, halide anions and/or crystallization water were present. In the compounds obtained, an essential influence on the formation of structures and crystal packing is exerted by the molecules of crystallization water and halide ions. Diethylammonium and nicotinamidium compounds, whose structures do not contain other ions and contain sufficiently strong non-covalent interactions, best bind hexahalotechnetates. π-Stacking interactions, anion–π interactions, and halogen bonds were found in the structures. The percentage contribution of the H⋯Hal/Hal⋯H interactions in the transition from fluorine to bromine in TcHal62− anions decreases, while the contribution of interactions of other types increases. The greatest variety of interactions in anions is observed for compounds of caffeinium and nicotinamidium with TcBr62−. The paper considers the processes of thermolysis of some new and previously known CatnTcHal6 compounds with various cations. It is shown that the thermal stability of the compounds is only due to the properties of the organic cation and does not depend on the nature of the halogen. The proposed stages of the process of thermolysis of the TcHal62− anion, accompanied by the reduction of technetium to metal, have been established. [ABSTRACT FROM AUTHOR]

Hybrid halocuprates(I) are nowadays the subject of intensive studies as promising materials for various optoelectronic applications. This class of materials is characterized by wide structural diversity enabled by a great variety in the size and shape of organic cations. Therefore, the study of composition–structure–property relationships is a key step for the rational design of new halocuprate materials with desired properties. In this paper, we comprehensively studied MABr/CuBr and FABr/CuBr systems (MA+ = methylammonium and FA+ = formamidinium) and established the existence of five novel phases (namely, MACu2Br3, FA2[Cu4Br6], MACuBr2, FACuBr2, and FA3CuBr4) related to four different structural types and three distinct A+ : Cu+ stoichiometries (A+ = MA+/FA+). The optical properties of the discovered phases are studied by absorption and low-temperature photoluminescence spectroscopy. Based on a crystal–chemical analysis, we explained a unique structural diversity of the MA- and FA-based bromocuprates, as well as revealed new structure–property relationships. [ABSTRACT FROM AUTHOR]

Hydrothermal conversion of actinide oxalates has recently gained attention as an innovative fabrication route for nuclear fuels but has remained mainly limited to tetra- or tri-valent cations. We report herein the reductive conversion of mixtures of uranyl and oxalate ions into UO2+x oxides under mild hydrothermal conditions (T = 250 °C). A multi-parametric study first led to specifying the optimal conditions in terms of pH, oxalate/U ratio and duration to provide a quantitative precipitation of uranium in the hyper-stoichiometric dioxide form with pH = 0.8; R = noxalate/nU = 3, and t = 72 hours. Particularly, pH was evidenced as a key parameter, with 3 different compounds obtained over a range of only 0.4 units. The mechanism leading to the formation of UO2+x was then investigated thanks to an in situ XANES study. Analysis of the supernatant showed that U(VI) was quickly reduced into U(IV) thanks to the presence of oxalates and/or their decomposition products in solution, following first-order kinetics. Tetravalent uranium was then hydrolysed, leading to the precipitation of UO2+x as the only crystalline phase. This study thus demonstrates that the hydrothermal conversion of actinide oxalates into oxides is an extremely versatile tool that can be implemented in a large variety of chemical systems, particularly in terms of the oxidation state of the cations initially present in solution. [ABSTRACT FROM AUTHOR]

Reactions of bromoantimonate(III) containing solutions with Br2 in the presence of different organic cations result in structurally highly diverse crystalline products readily forming halogen bonds (XBs). Herein, we add six new compounds to this palette using 1,n-bis(3-methylpyridinium)- or (4-methylpyridinium)alkane dications; the complexes were characterized using X-ray diffraction and thermogravimetric analysis (TGA). Further, we discuss all previous results in this field, including quantum chemistry investigation of the features of XBs in such compounds. [ABSTRACT FROM AUTHOR]

Co(III) complexes of the N-heterocyclic carbene ligand PY4Im (PY4Im = (1,3-bis(bis(2-pyridyl)methyl)imidazol-2-ylidene)) having the general formula [(PY4Im)Co(X)](ClO4)n (X = NCMe; n = 3: OH−, N3−, NCS−, ONO−, F−; n = 2: O2CO2−, n = 1; (N3−)3, n = 0) were prepared and structurally characterised. X-ray structural data are consistent with the presence of a trans influence due to the coordinated carbene carbon, and this is also supported by computational results. 13C NMR spectra of the complexes did not display peaks corresponding to the carbene carbon, except in the case of the [(PY4Im)Co(O2CO)]+ cation, where a peak at δ = 170.21 ppm was observed. However, HMBC spectra allowed indirect determination of the chemical shifts of the carbene carbon in the remaining complexes, owing to the geometry of the PY4Im ligand. Calculated 13C chemical shifts for the complexes showed very good agreement with the experimental values for all but the carbene carbon atoms in all cases. [ABSTRACT FROM AUTHOR]

The detection of excess toxic anions or cations in an aqueous solution through various fluorescent materials such as organic or inorganic fluorescent materials has aroused significant interest recently. Herein, a new tetraimidazole ligand 1,3-bis(1-imidazolyl)-5-[3,5-bis(1-imidazolyl)-phenoxymethyl]-benzene (timpb) and its two Cd(II) metal–organic frameworks {[Cd2(1,4-bdc)2(timpb)]·5.5(H2O)}n (1) (1,4-benzenedicarboxylic acid = 1,4-H2bdc) and {[Cd2(4,4′-bpdb)2(timpb)]·(MeCN)·2.5(H2O)}n (2) (4,4′-biphenyldicarboxylic acid = 4,4′-H2bpdb) were synthesized. Through X-ray single crystal diffraction analysis, 1 can be considered as a 2-fold interpenetrating pillared-bilayer framework formed by linking [Cd2(1,4-bdc)4]n layers with pairs of timpb ligands, whereas 2 exhibits a 2-fold interpenetrating 3D honeycombed framework formed by linking [Cd(4,4′-bpdb)]n chains with timpb ligands. The solid-state luminescent properties of timpb, 1 and 2 at ambient temperature were also investigated. Moreover, timpb acted as a potential luminescent sensor for the detection of cations Fe3+ or Cu2+ and the anion Cr2O72−, whereas 1 displayed high sensitivity toward the cation Fe3+ and anion Cr2O72−. [ABSTRACT FROM AUTHOR]

ortho-N-Substituted pyridinium cations with the weakly coordinating anion [B(C6F5)4]− have been studied and crucial structural features in the sp2 C–H borylation catalysis of 3-methylthiophene have been identified. The electron-deficiency of the aromatic core of the cation is essential for activity together with accessible protons. The spectroscopic yield of the borylation of 3-methylthiophene with catecholborane (CatBH) was optimized up to 86% and the method was further applied to other substrates such as N-alkylbenzenes. A mechanistic DFT study revealed the rate-limiting step in the catalysis to be the liberation of molecular H2 (ΔG‡ = 27.5 kcal mol−1), whereas the overall reaction was found to be exergonic by 5.1 kcal mol−1. [ABSTRACT FROM AUTHOR]

A series of single crystals of Ni3−xCoxB2O6 compounds with the kotoite structure and with different concentrations of transition metal ions (x = 0; 0.19; 0.6; 0.93 and 2) were obtained. The lattice parameters and atomic coordinates were determined using X-ray diffraction. The theoretical calculations using the WIEN2k package predict that nickel ions tend to occupy the 4f crystallographic position, while cobalt ions tend to occupy the 2a crystallographic position. The study of the diffuse scattering spectra and comparison of the Racah parameters for the compounds Ni3B2O6 and Co2NiB2O6 provides experimental evidence that nickel ions occupy crystallographic position 4f. [ABSTRACT FROM AUTHOR]

In this paper, we focused on the influence of common serum cations on monosodium urate monohydrate (MSUM) crystal nucleation determined from cumulative probability distributions (CPDs) of solute crystal nucleation events as a function of time. Surprisingly, with an increase in the concentration of additive ions, striking "opposite effects" were observed for cations, enhancing nucleation at first followed by suppressing nucleation at physiological pH and ionic strength. This enhancing nucleation phenomenon cannot be explained based on colloidal theories or simple descriptors, such as ion size, but it is consistent with the cationic efficacy for inducing an increase in the proportion of growth units of MSUM. [ABSTRACT FROM AUTHOR]

Selective identification of metal ions as well as their removal is possible when a sensing unit is anchored to a solid support. In this paper, functionalized mesoporous silica with a pendant rhodamine 6G moiety (R6FMS) has been obtained by successive grafting of an aldehyde derivative of bisphenol A followed by rhodamine 6G over a 3-aminopropyl anchored mesoporous silica framework. The materials have been characterized by powder X-ray diffraction, nitrogen sorption and electron microscopy studies, FT-IR and solid state MAS NMR spectral studies, and thermal analysis. In ethanol, the colorless silica material gives pink coloration in the presence of Al3+, Cr3+, Fe3+ and Cu2+ which is also clearly evident from the generation of an absorption peak at 525 nm. Upon excitation at 500 nm, the fluorescence intensity of the probe increases by 36-, 17-, 40- and 89-fold in the presence of Al3+, Cr3+, Fe3+ and Cu2+ ions, respectively. This suggests that R6FMS is a colorimetric and fluorescent chemosensor for these cations in ethanol. However, when the solvent is changed from ethanol to water, it becomes a selective chemosensor only for Cu2+ and Hg2+, by the generation of a pink color and strong fluorescence at ca. 550 nm, thereby discriminating the trivalent cations. Cations induce the opening of the spirolactam ring resulting in pink coloration and strong fluorescence. The quantum yield and lifetime of the probe have been increased considerably in the presence of these cations in ethanol as well as in aqueous media. The detection limit values for these cations range from 10−6 to 10−8 M. R6FMS has been used to remove Hg2+ and Cu2+ from their aqueous solution with a maximum adsorption capacity of 35 mg g−1 and 148 mg g−1 for Cu2+ and Hg2+, respectively. [ABSTRACT FROM AUTHOR]

The [18F]fluorobenzyltriphenylphosphonium cation ([18F]FBnTP) has emerged as a highly promising positron emission tomography (PET) tracer for myocardial perfusion imaging (MPI) due to its uniform distribution in the myocardium and favorable organ biodistribution demonstrated in preclinical studies. However, a complex and low-efficiency radiosynthesis procedure has significantly hindered its broader preclinical and clinical explorations. Recently, Zhang et al. developed a pinacolyl arylboronate precursor, enabling a one-step synthesis process that greatly streamlines the production of [18F]FBnTP. Building upon this progress, our group successfully adapted the approach to a microdroplet reaction format and demonstrated improved radiosynthesis performance in a preliminary optimization study. However, scaling up to clinical dose amounts was not explored. In this work, we demonstrate that scale-up can be performed in a straightforward manner using a "numbering up" strategy (i.e. performing multiple droplet reactions in parallel and pooling the crude products). The resulting radiochemical yield after purification and formulation was high, up to 66 ± 1% (n = 4) for a set of experiments involving pooling of 4 droplet reactions, accompanied by excellent radiochemical purity (>99%) and molar activity (339–710 GBq μmol−1). Notably, we efficiently achieved sufficient activity yield (0.76–1.84 GBq) for multiple clinical doses from 1.6 to 3.7 GBq of [18F]fluoride in just 37–47 min. [ABSTRACT FROM AUTHOR]

Although numerous non-metallic pentazolate (cyclo-N5−) salts have been synthesized and investigated, no cyclo-N5− salt containing cage-like cations has been reported to date. To identify how cage-like cations impact the structures and properties of cyclo-N5− salts, we synthesized and examined two cyclo-N5− salts (C10H18N6 and C6H14N12) based on cage-like cations. Furthermore, the structures and performances of these cyclo-N5− salts were compared. The results suggest that the cyclo-N5− salts based on cage-like cations possess good insensitivity (IS > 40 N, FS > 360 J), which provides a good idea for developing new energetic salts with low sensitivity. Furthermore, we compared C6H14N12 with chain-like cationic pentazolate salt based on a similar structure and reported that C6H14N12 demonstrated improved density and detonation performance. This result indicates that selecting cage-like cations as antagonistic ions to cyclo-N5− anions may be an improved choice compared to chain-like cations having similar structures. [ABSTRACT FROM AUTHOR]

Subphthalocyanines (SubPcs) and their aza-analogues (SubTPyzPzs) are fluorophores with strong orange fluorescence emission; however, their sensing ability towards metal cations remains uncharted. To fill this gap, we have developed an efficient method for introducing aza-crown moieties at the axial position of SubPcs and SubTPyzPzs to investigate the structure–activity relationship for sensing alkali (Li+, Na+, K+) and alkaline earth metal (Ca2+, Mg2+, Ba2+) cations. SubPcs showed better photostability than SubTPyzPzs and even a commonly utilized dye, 6-carboxyfluorescein. Selectivity toward metal cations was driven by the size of the aza-crown, irrespective of the counter anion. The stoichiometry of binding was found to be 1 : 1 in all cases, and the interaction between SubPcs and cations was characterized by the corresponding apparent binding constants (Ka). Notably, an unusually strong interaction of all sensoric SubPcs with Ba2+ compared to other studied cations was demonstrated. The role of the surrounding environment, i.e. the addition of water or methanol, in sensing cations is shown in detail as well. Selectivity towards K+ over Na+ was demonstrated in aqueous media with SubPcs bearing the 1-aza-6-crown-18 moiety in Tween 80 micelles. In this case, a 5-fold increase of the fluorescence quantum yield was observed upon binding K+ ions. The high brightness, photostability, and sensing activity in aqueous media make SubPc macrocycles promising fluorophores for metal cation sensing. [ABSTRACT FROM AUTHOR]

In recent years, hybrid manganese(II) halides (HMHs) have attracted wide attention due to their impressive optical properties, low toxicity, and facile synthetic processibility. Being effective reabsorption-free phosphors, these compounds demonstrate the potential to be used as low-cost solution-processable scintillators. However, most of the HMHs studied to date contain bulk organic cations and, as a result, are characterized by low density and low X-ray stopping power. For this reason, we studied manganese(II) bromides with compact organic cations such as formamidinium (FA+) and acetamidinium (AcA+). In particular, we synthesized four new phases, two of which are characterized by octahedral coordination of manganese ions ((FA)MnBr3 and (AcA)MnBr3) and red emission, whereas the other two have tetrahedrally coordinated Mn2+ ions ((FA)3MnBr5 and (AcA)2MnBr4) and green emission. Photoluminescence (PL) and radioluminescence measurements demonstrated high PL quantum yields and reasonable scintillation light yields of acetamidinium-based compounds. In addition, unlike most known HMH-based scintillators, the discovered materials have a relatively high density due to the small fraction of the volume occupied by organic cations, so their X-ray attenuation coefficients are comparable to the well-known oxide scintillators. [ABSTRACT FROM AUTHOR]

Achieving high luminescent quantum yield and thermal stability of phosphors simultaneously remains challenging, yet it is critical for facilitating high-power white light emitting diodes (WLEDs). Herein, we report the design and preparation of the layered structure BaZnB4O8:xEu3+ (0.10 ≤ x ≤ 0.60) red phosphors with high quantum yield (QY = 76.5%) and thermal stability (82.8%@150 °C) by the traditional solid-state reaction method. The results of XRD and Rietveld refinement show that the presence of Eu3+ ions at Ba2+ sites causes the formation of cation (Zn2+/Ba2+) vacancies in the lattice. The PL and PL decay results reveal that the quenching concentration of BZBO:xEu3+ phosphors is as high as 50%, and the lifetime remains unchanged with Eu3+ concentration due to the unique structure of the host and the cation vacancies generated by the heterovalent substitution. Furthermore, on a 395 nm near-UV chip, a pc-WLED device with exceptional optical performance (CCT = 4415 K, CRI = 92.1) was realized using the prepared BZBO:0.50Eu3+ as a red phosphor. Simple synthesis and excellent performance parameters suggest that the reported BaZnB4O8:xEu3+ phosphors have promising applications in high-power pc-WLEDs. At the same time, it also indicates that cationic vacancy engineering based on heterovalent ion substitution is a potential strategy for improving luminescence quantum yield and thermal quenching performance. [ABSTRACT FROM AUTHOR]

Samples of the pseudo-binary system Na2−xLixGa7 (x ≤ 1) were synthesized from the elements at 300 °C in sealed Ta ampoules or by the reaction of Na2Ga7 with LiCl. The peritectic formation temperature decreases with increasing Li content from 501(2) °C (x = 0) to 489(2) °C (x = 1). The boundary compositions Na2Ga7 and Na1Li1Ga7 crystallize with different structure types related by a group–subgroup relation. While the Na-rich compositions (x ≤ 0.5) represent a substitutional solid solution (space group Pnma), the Li-rich compositions feature an unconventional replacement mechanism in which Li atoms occupying interstitial positions induce vancancies at the Na positions (space group Cmce). The crystal structure of Na1Li1Ga7 (a = 8.562(1) Å, b = 14.822(2) Å, c = 11.454(2) Å; Z = 8) was determined from X-ray single-crystal diffraction data, and reveals an anionic framework comprising 12-bonded Ga12 icosahedra and 4-bonded Ga atoms, with alkali–metal atoms occupying channels and cavities. The arrangement of cations makes NaLiGa7 a new structure type within the MgB12Si2 structure family. Band structure calculations for the composition NaLiGa7 predict semiconducting behavior consistent with the balance [Na+]2[Li+]2[(Ga12)2−][Ga–]2, considering closo Wade clusters [(12b)Ga12]2− and Zintl anions [(4b)Ga]−. Susceptibility measurements indicate temperature-independent diamagnetic behavior. [ABSTRACT FROM AUTHOR]

A careful selection of organic and inorganic components enables the production of unusual structure types with promising practical properties by facile syntheses. In this paper, we describe novel supramolecular architectures comprising organic adamantane-like divalent building blocks and iodide or polyiodide anions. Highly acidic conditions facilitated the formation of a doubly protonated organic ligand out of 5,7-dimethyl-1,3-diazaadamantane that generates three different crystal structures with inorganic counterions. In these structures, cationic substructures are constructed by transforming neutral organic ligands into [(C10N2H20)I]+ or [(C10N2H20)(H2O)]2+ cations, which crystallize with charge-compensating iodine-based anions of different complexities. All three crystal structures are characterized by various noncovalent forces, ranging from strong (N)H⋯I, (O)H⋯I, and (N)H⋯O hydrogen bonds to secondary and weak I⋯I interactions. Raman and diffuse reflectance spectroscopy as well as DFT calculations were employed to describe the electronic structures and optical properties of new supramolecular architectures, with particular attention to the role of non-covalent interactions. [ABSTRACT FROM AUTHOR]

In this paper we probe the reactivity of the borenium cations [C3H2(NCH2C6H4)(NCH2Ph)BH][B(C6F5)4] 2 and [C3H2(NCH2C6H4)2B][B(C6F5)4] 3. The reactions of 2 with cyclohexene or 3,3-dimethyl-1-butene gave the alkyl-aryl borenium salts [PhCH2(CHN)2CCH2C6H4BR][B(C6F5)4] (R = Cy 4, CH2CH2tBu 5) while the corresponding reactions with diphenylacetylene, 1-hexyne and 1-phenyl-1-propyne gave the aryl–alkenyl borenium cation salts [PhCH2(CHN)2CCH2C6H4BC(R1)C(H)R2][B(C6F5)4] (R1 = R2 = Ph 6, R1 = H, R2 = C4H97, R1 = Me, R2 = Ph 8a, R1 = Ph, R2 = Me 8b). In contrast, the reaction of 2 with ethynyldiphenylphosphane or 2-vinylpyridine lead to the formation of the adducts, [PhCH2(CHN)2CCH2C6H4B(H)P(Ph2)CCH][B(C6F5)4] 9, [PhCH2(CHN)2CCH2C6H4B(H)NC5H4C(H)CH2][B(C6F5)4] 10, respectively, while the more bulky donor H2C＝C(Ph)PMes2 gave 1,2-hydroboration of the phosphinoalkene affording [PhCH2(CHN)2CCH2C6H4BCH2CH(Ph)PMes2][B(C6F5)4] 11. In another vein of reactivity, one or two equivalents of the FLP, PtBu3/B(C6F5)3 is shown to react with 3 to give the zwitterionic borenium-borate species [C2H2(NCH(BC(CHNCH2C6H4)2)C6H4)(NCH(B(C6F5)3)C6H4)CB] 12 and the anionic bis-borate species[tBu3PH][C2H2(NCH(B(C6F5)3)2C6H4)2CB] 13. The implications of these findings are discussed. [ABSTRACT FROM AUTHOR]

Herein, a new organic cationic matrix [N(CH3)4]3MoO3F3 suitable for Mn4+ doping was constructed. Due to the large steric hindrance of N[CH3]4+ (TMA), charge compensation defects can be effectively prevented in the heterovalent Mn4+-doping process, and a high IQE (91.05%) was obtained. Through the cation co-doping strategy, Mg2+/Zn2+/Li+ cations were introduced into the Mo6+ cationic site, which improved the crystallinity of the matrix and reduced energy losses, so as to improve luminescence intensity, QE, thermal stability, water stability and other spectral properties. Meanwhile, [N(CH3)4]2TiF6:Mn4+ phosphors with the same TMA organic cation and equivalent Mn4+ doping were synthesized for comparison, and the effects of the Mg2+ cation co-doping strategy on the spectral properties of phosphors with different matrix types (fluoride/oxyfluoride) and substitution types (equivalent/non-equivalent) were analyzed. These findings provide the basis for the preparation of new luminescent materials. Furthermore, according to the optical properties exhibited by these phosphors, they are packaged into WLED devices with excellent photoelectric properties, which are suitable for indoor lighting and display fields. [ABSTRACT FROM AUTHOR]

Phosphinoborenium cations stabilized by N-heterocyclic carbenes (NHCs) were synthesized via the reaction of bromo(phosphino)boranes with NHCs. Their structures were investigated by heteronuclear magnetic resonance spectroscopy, X-ray diffraction, and density functional theory calculations. They possess a planar trigonal boron center directly bonded with the pyramidal phosphanyl group (PR2) and can be treated as cationic phosphinoboranes. The reactivity of the selected NHC-phosphinoborenium cation was tested toward AuCl·SMe2 and Ph2PCl. In both reactions, the titled compound acted as a phosphido group donor under heterolytic cleavage of the P–B bond. Control experiments with parent phosphinoborane emphasized differences between the reactivity of low-coordinate neutral and cationic species with P–B functionality. [ABSTRACT FROM AUTHOR]

Synthesis of a series of hydrocarbon-soluble triarylamines bearing F, CF3, and Br substituents showing quasi-reversible redox events in the 0.59–1.32 V range is reported. Chemical oxidation of the amines was carried out with 0.5PhI(OAc)2/Me3SiX/Na[RCB11Cl11] (X = Cl or OTf, R = H or Me), and a few aminium salts were isolated as pure solids. [ABSTRACT FROM AUTHOR]

In this paper, some cationic dipeptides from scallop (Patinopecten yessoensis) male gonads (SMGs), which can synergistically gel with ι-carrageenan (ι-C), were screened by the in silico approach. Fourteen protein sequences of SMGs were obtained by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and nano liquid chromatography-mass spectrometry/mass spectrometry (nanoLC-MS/MS) analysis and were then hydrolyzed via in silico simulation. A total of 414 sequences were obtained with 56 duplicates, half of which were positively charged at pH 7. Among the cation sequences, 171 had good water solubility, including two amino acids (Lys and Arg). The molecular weight analysis of the cationic water-soluble sequences showed that 0.2-0.3 kDa accounted for the highest proportion. Based on the obvious synergistic effect of Lys and ι-C, 11 Lys-containing dipeptides, including Ser-Lys (SK), Thr-Lys (TK), Trp-Lys (WK), Ala-Lys (AK), Leu-Lys (LK), Gly-Lys (GK), Val-Lys (VK), Cys-Lys (CK), Asn-Lys (NK), Phe-Lys (FK), and Met-Lys (MK), were finally screened out to study gelation with ι-C. It was found that the dipeptides/ι-C formed firm gels except WK/ι-C. The values of the storage modulus (G') of 11 dipeptides/ι-C were investigated by a rheometer. The G' of 8 dipeptides/ι-C was higher than 1000 Pa. These results indicated that the in silico-screened dipeptides from SMGs can form composite gels with ι-C, which can be used for the design and development of functional hydrogels.

Oxide semiconductors with mixed-valence states generally exhibit excellent optoelectronic and photochemical properties due to facile charge transfer in redox reactions. In this work, we investigate the effects of mixed alkali on the optical absorption, luminescence spectra and photocatalytic abilities of (Na1−xKx)Sb3O7 nanoparticles. All the samples are fabricated using a simple one-step hydrothermal method. The structural studies show that the largest substitution of K+ ions in (Na1−xKx)Sb3O7 is at x = 0.3. In hydrothermal synthesis, the mixed arrangement of K+ and Na+ in (Na1−xKx)Sb3O7 has an influence on the crystal shape of particles. NaSb3O7 develops into a regular cube shape. With the increase of K+ ions in (Na1−xKx)Sb3O7, the edges and corners of the cube are further ground off, resulting in irregularly spherical particles. This mixed-alkali antimonite belongs to a p-type indirect allowed transition semiconductor, and the optical band gap is 2.71 eV (x = 0.3). The intrinsic luminescence of NaSb3O7 is detected at 540 nm, which is nearly quenched in Na0.7K0.3Sb3O7. It is demonstrated that the substitution of K+ in NaSb3O7 significantly increases the photodegradation of RhB solutions. There are two types of Sb cations, i.e., Sb5+ and Sb3+ mixed in the structure. The improved photocatalysis is attributed to the charge mediators between Sb5+/Sb3+ couples. The experiment shows that co-doping cations in antimonite oxides may be one of the strategies to improve photochemical properties. [ABSTRACT FROM AUTHOR]

Diazulenylmethyl cations bridged with a germanium and tin moiety were synthesized. In these cations, the nature of these elements has impacts on the chemical stability and photophysical properties. Upon aggregation, these cations exhibit absorption bands in the near-infrared region, which are slightly blue-shifted compared to those of silicon-bridged congeners. [ABSTRACT FROM AUTHOR]

Systemic acquired resistance (SAR) is one of the most promising ways to support plants in the fight against viruses. Using this approach biological or chemical factors interact with plants and stimulate their immune system against infections before infection occurs. This paper presents synthesis, physical properties, phytotoxicity and SAR induction efficacy of 15 ionic liquids, derivatives of SAR inducers paired with the cholinium cation, an essential nutrient for organisms. SAR induction efficacy tests were performed on tobacco Nicotiana tabacum var. Xanthi infected by tobacco mosaic virus (TMV). [ABSTRACT FROM AUTHOR]

The concept of nonmetallic frustrated cations has been used in small molecule activation. The in situ generated ambiphilic phosphinoborinium cation activated phenyl isocyanate, diisopropylcarbodiimide, and acetonitrile under very mild conditions without any catalyst, yielding single-, double-, or mixed-activation products. Furthermore, the mechanisms of the reactions of the phosphinoborinium cation with small molecules were elucidated using density functional theory calculations. [ABSTRACT FROM AUTHOR]

We report the synthesis and structural characterization of a series of heterometallic rings templated via alkylammonium or imidazolium cations. The template and preference of each metal's coordination geometry can control the structure of heterometallic compounds, leading to octa-, nona-, deca-, dodeca-, and tetradeca-metallic rings. The compounds were characterized by single-crystal X-ray diffraction, elemental analysis, magnetometry, and EPR measurements. Magnetic measurements show that the exchange coupling between metal centres is antiferromagnetic. EPR spectroscopy shows that the spectra of {Cr7Zn} and {Cr9Zn} have S = 3/2 ground states, while the spectra of {Cr12Zn2} and {Cr8Zn} are consistent with S = 1 and 2 excited states. The EPR spectra of {(ImidH)-Cr6Zn2}, {(1-MeImH)-Cr8Zn2}, and {(1,2-diMeImH)-Cr8Zn2} include a combination of linkage isomers. The results on these related compounds allow us to examine the transferability of magnetic parameters between compounds. [ABSTRACT FROM AUTHOR]

New iodobismuthate hybrids with lanthanide complex counter cations, [Ln(DMF)8][Bi2I9] (Ln = La (1), Eu (2)) and [Tb(DMF)8]2[Bi2I9]2 (3) (DMF = N,N-dimethylformamide), were prepared using solvated Ln(III) complexes formed in situ as structure-directing agents. The dimeric [Bi2I9]3− anion moieties of compounds 1–3 are aggregated by two slightly twisted BiI6 octahedra through face-sharing mode. The different crystal structures of 1–3 are due to the different I⋯I and C–H⋯I hydrogen bond interactions. Compounds 1–3 have narrow semiconducting band gaps at 2.23, 1.91 and 1.94 eV, respectively. Under Xe light irradiation, they exhibit steady photocurrent densities that are 1.81, 2.10 and 2.18 times higher than that of pure BiI3, respectively. Compounds 2 and 3 exhibited higher catalytic activities than 1 in the photodegradation of organic dyes CV and RhB, which are attributed to the stronger photocurrent response derived from the redox cycles of Eu3+/Eu2+ and Tb4+/Tb3+. [ABSTRACT FROM AUTHOR]

The valorization of abundant agrowastes into chemicals and advanced materials is of key importance in the context of the circular bioeconomy and biorefinery. Herein, we report the ionothermal carbonization (ITC) of sugarcane bagasse, a fibrous residue made of lignocellulose, to engineer advanced carbonaceous materials, namely ionochars. We prepared a series of imidazolium tetrachloroferrate ionic liquids (IL) bearing modular substituents, e.g., alkyl chains with different lengths or benzyl groups. The effect of the cation on both textural and morphological properties is highlighted. Ionochars with high specific surface area (up to 800 m2 g−1), tuneable pore volume (up to 0.8 cm3 g−1), singular nanostructures and adjustable CO2 uptake/retention were obtained. [ABSTRACT FROM AUTHOR]

Cobalt-based spinel oxides are considered potential candidates for the oxygen evolution reaction (OER) due to their abundant valence changes and promising electrochemical activity, but their low intrinsic activity hinders their practical applications. Herein, we synthesize a series of CoCeMOx (M = Zn, Ni, Ru, Er, Mg, Mn, Sn) derived from CoCeM coordination-driven self-assembled aggregates (CDSAAs) using a general ion exchange and subsequent calcination method. Interestingly, CoCeMOx exhibit different morphologies from porous nanospheres, particle-stacked nanospheres, to hollow nanospheres as the third metal element is altered. Markedly, CoCeZnOx porous nanospheres (PNs) exhibit the best OER performance. The XPS results reveal that the existence of CeO2 and Zn2+ ions significantly increased the Co2+/Co3+ ratio and the content of oxygen vacancies in Co3O4. Furthermore, Co2+ can be used as highly reactive sites to form CoOOH and the high content of oxygen vacancies can optimize the oxygen-containing intermediate adsorption energy, both of which can effectively improve the OER performance. Therefore, well-designed CoCeZnOx PNs demonstrate high OER activity with a lower overpotential (η = 333 mV) than that of commercial RuO2 (344 mV) in 10 mA cm−2, a Tafel slope of 98 mV dec−1, and a long-term durability of 45 h. This work may provide some inspiration for the design of trimetallic oxide nanomaterials. [ABSTRACT FROM AUTHOR]

Solvated tungsten iodide cluster compounds are presented with the homoleptic cluster cation [(W6I8)(CH3CN)6]4+ and the heteroleptic [(W6I8)I(CH3CN)5]3+, synthesized from W6I22 in acetonitrile. Crystal structures were solved and refined on deep red single-crystals of [(W6I8)(CH3CN)6](I3)(BF4)3·H2O, [(W6I8)I(CH3CN)5](I3)2(BF4), and on a yellow single-crystal of [W6I8(CH3CN)6](BF4)4·2(CH3CN) on the basis of X-ray diffraction data. The structure of the homoleptic [(W6I8)(CH3CN)6]4+ cluster is based on the octahedral [W6I8]4+ tungsten iodide cluster core, coordinated by six apical acetonitrile ligands. The electron localisation function of [(W6I8)(CH3CN)6]4+ is calculated and solid-state photoluminescence and its temperature depedence are reported. Additionally, photoluminescence and transient absorption measurements in acetonitrile are shown. Results of the obtained data are compared to compounds containing [(M6I8)I6]2− and [(M6I8)L6]2− (M = Mo or W; L = ligand) clusters. [ABSTRACT FROM AUTHOR]

Heterobimetallic tert-butoxides of alkali metal cations with tetravalent actinide centers exhibit two distinctive structural motifs, [AnM2(OtBu)6] and [AnM3(OtBu)7] (AnIV = Th, U and MI = Li, Na, K, Rb, Cs), evidently governed by the size of the alkali metal ions. Both [AnM3(OtBu)7] AnM3 (AnIV = U, MI = Li; AnIV = Th, MI = Li, Na) and [AnM2(OtBu)6] AnM2 (AnIV = U, MI = Na–Cs; AnIV = Th, MI = K–Cs) compounds are obtained in nearly quantitative yields by reacting actinide and alkali metal silyl amides with an excess of tert-butyl alcohol. The AnM3 complexes form a cubane-type coordination motif, whereas the AnM2 complexes display a geometry resembling two face-shared bipyramids. The sodium derivatives of thorium and uranium (ThNa3 and UNa2) allow the determination of the structural transition threshold as a function of the ratio of the ionic radii ri(AnIV)/ri(MI). The AnM3 complexes are formed for ratios above 0.92 and the AnM2 type is formed for ratios below 0.87. All compounds are unambiguously characterized in both solution and solid states by NMR and IR spectroscopic studies and single crystal X-ray diffraction analyses, respectively. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) hybrid perovskites have exhibited multiple features owing to their multiple quantum well structure. Here, we show the synthesis and characterization of 2D mixed-halide Cu-based perovskite crystals, R2Cu(Cl/Br)4, with three different alkyl chains, where R is methyl, butyl, or hexyl ammonium cations. Exfoliated perovskite flakes exhibit reversible thermochromism with changes in color darkness with temperature variation. Differential scanning calorimetry and temperature-dependent X-ray diffraction measurements reveal that the thermochromic behavior mechanism of R2Cu(Cl/Br)4 depends on the nature of the alkyl chain. [ABSTRACT FROM AUTHOR]

The reactivity between 2-(p-tolyl)selenopheno[2,3-b]pyridine (L) and ICl in MeCN is presented. Single crystal structure analysis revealed the formation of two distinct crystalline materials both featuring the protonated 2-(p-tolyl)selenopheno[2,3-b]pyridinium cation [HL]+. Colourless crystals were identified as the dihydrate salt [HL]Cl·2H2O (1), and dark-red crystals as compound {[HL]+[I2Cl]−}3·1/2I2 (2) that features the peculiar presence of the rare non-classical [I2Cl]− interhalide. Halogen Bonds (XBs) between the cocrystallized I2 molecule and [I2Cl]− anions led to the novel overall discrete [I10Cl4]4−H-shaped polyinterhalide formation, which is stabilized through hydrogen bonds (HBs) with the templating [HL]+ cations. The experimental observations are supported by extensive theoretical calculations at the DFT level that were employed to study the role played by non-covalent interactions in the formation of the presented unique polyinterhalide. [ABSTRACT FROM AUTHOR]

Results from the determination of sixteen X-ray single crystal structures are reported for a series of 3-(4-alkoxyphenyl)-5-perfluoroalkyl-2,4-dimethyl-1,2,4-triazolium salts with tetrafluoroborate, triflate or bistriflimide anions, in which the lengths of the alkoxy and perfluoroalkyl chains are varied systematically. On account of these cations having a hydrocarbon, fluorocarbon and ionic part, they are classified as triphilic. All of the tetrafluoroborate salts crystallised in the P21/c space group, most as acetone solvates, while for the bistriflimide salts, four different space groups were found although all contained a P21 screw axis often with additional symmetry elements. Of the triflates, two crystallised in space groups with a P21 screw axis and two in P1¯. The organisation in the crystalline state tended to reflect the triphilic nature of the materials with cations and anions associating in repeating motifs, while the rest of the space was occupied by either hydrocarbon or fluorocarbon domains with only two exceptions. [ABSTRACT FROM AUTHOR]

We have used quantum chemical methods to study the structural principles and energetics of A-site ordered AA′B2O6 double perovskites. 33 combinations of A-site ordering and Glazer tilting have been systematically studied for the ferroelectric CaMnTi2O6 model system. The used approach was able to predict the correct combination of A-site ordering and tilting of octahedra in comparison to the experimentally known CaMnTi2O6. The energy differences between the various combinations of A-site ordering and tilt systems show a large variation of tens of kJ mol−1 per formula unit, which suggests that the methodology used here can be used as a starting point for making reliable predictions on the structures of yet unknown A-site ordered double perovskites. The energy differences due to A-site ordering and octahedral tilting were larger compared to the energy difference arising from ferroelectric distortion in CaMnTi2O6. The energy differences between various hypothetical double perovskite structures could be explained by studying their structural characteristics in detail. The relative energies are closely correlated with the Mn–O distances and Mn coordination in the studied structures. [ABSTRACT FROM AUTHOR]

Metal thiophosphates have aroused much research interest due to their structural chemistry and possible applications as infrared functional materials. In this study, five quaternary Sr-based alkali metal thiophosphates ASrPS4 (A = Li, Na, K, Rb, Cs) were obtained. Their structural comparison shows that their symmetry undergoes transformation from tetragonal (I41/acd) to monoclinic (P21/c) to orthorhombic (Pnma) system, which is induced by the cation size effects and coordination features of different alkali metal cations. The experimental and theoretical results demonstrate that the band gaps of all title compounds are large, namely 3.6–3.9 eV (experimental results) and 3.78–4.12 eV (HSE06). Theoretical analyses indicate that the [PS4] group could be regarded as a good unit for designing wide band gap compounds, and the birefringence of NaSrPS4 is 0.08 at the fundemental 1064 nm wavelength, which shows that it may be a potential infrared birefringent material. [ABSTRACT FROM AUTHOR]

Chiral 2D and quasi-2D hybrid organic–inorganic perovskites (HOIPs) are emerging as promising materials for a variety of applications principally related to optoelectronics and spintronics, thanks to the combined benefits deriving from both the chiral cation and the perovskite structure. Since its recent birth, this research field is tremendously growing, focalizing on the chemical composition tuning to unveil its influence on the related functional properties as well as on developing devices for practical applications. In this review, we focused on the properties of 2D and quasi-2D chiral HOIPs, firstly providing an overview on their chiroptical behaviour followed by their potential exploitation in devices investigated so far for various applicative fields. [ABSTRACT FROM AUTHOR]

For improving the overall energy storage performance of aqueous zinc-ion battery (ZIB) systems, it is important to identify new cathode materials with superior characteristics. Along these lines, in this work, Na, K, and structural water were pre-inserted in vanadium oxide via a simple solution reaction method at room temperature. More specifically, Na2V6O16·1.96H2O (NVO) and K2V6O16·2.13H2O (KVO) nanorods were successfully prepared using CH3COONa and CH3COOK, respectively, and commercial V2O5 powder as starting materials. The NVO and KVO nanorods exhibited high Zn2+ storage ability; while the specific capacity of the NVO cathode reached 366.8 mAh g−1 at 0.3 A g−1, its capacity retention was 86.6% after 1000 consecutive cycles at 3 A g−1, and the KVO cathode also showed impressive performance. NaV3O8 and KV3O8 were prepared for comparison by annealing NVO and KVO at high temperatures. The comparison of their cycling stability, Zn2+ diffusivity coefficients, and electronic conductivity with the same characteristics of both NVO and KVO cathodes demonstrated that the presence of structural water had a positive impact on the electrochemical performance of the prepared materials. The high performance of NVO and KVO is mainly attributed to the synergistic effect between structural water and metal ions. [ABSTRACT FROM AUTHOR]

The synthesis of 1-silolyl and 1-germolyl triflates from the corresponding chlorides by salt metathesis reaction is reported. These covalent triflates are ideal starting materials for the preparation of ionic silolyl- and germolyl-imidazolium triflates by their reaction with N-heterocyclic carbenes. Similarily, ionic silolyl- and germolyl-oxophosphonium triflates are obtained by substitution of the triflate group by triethylphosphane oxide Et3PO. The analysis of their 31P NMR chemical shifts according to the Gutmann–Beckett method reveal the high Lewis acidity of the underlying silolyl and germolyl cations. Further analysis of structural and NMR parameters of the silolyl- and germolyl-imidazolium and oxophosphonium triflates indicates that these compounds are covalently bonded silole and germole derivatives with insignificant contributions from silolyl- or germolyl cations. Silolyl and germolyl triflates are however synthetic equivalents of these cations and might serve as a source for electrophilic silolyl and germolyl units. [ABSTRACT FROM AUTHOR]

The negatively charged polyuronates exhibit a high affinity for binding the bivalent metal cations. This feature is used for the removal of heavy metals from aqueous solutions. The aim of the present paper is to: (i) present the computational strategy, helpful in simulating the metal ion–uronate complexes; (ii) illustrate its applicability to the example of the α-l-guluronate anion (the monomeric unit of alginates) interacting with bivalent metal ions: Zn2+, Cu2+, Cd2+, Mn2+ and Co2+. The study was carried out on the basis of the ‘hybrid’ molecular dynamics simulations in which the selected part of the system (uronate anions and metal cations) is treated with the ab initio level of accuracy, whereas the interactions within the rest of the system are approximated by the classical force fields. The results allowed for determining the basic structural and energetic (for example, the free energy profiles associated with the cation binding–unbinding process) characteristics related to the metal ion–guluronate complexes. Most of the studied ions exhibited the preference for monodentate binding. Bidentate binding can be observed for Mn2+ and Co2+ (dominant binding mode) and Cd2+ (secondary binding mode). The calculated binding free energy order (Cu ＞ Co ＞ Zn ∼ Mn ＞ Cd) follows both the experimentally determined order of transition metal ion–alginate affinities and the metal–uronate interaction energies. The efficiency of the calculations and the general characteristics of the method allow for its potential use in simulations of other uronate–metal ion systems, increasing the range of methods which can be used for studying the metal biosorption processes. [ABSTRACT FROM AUTHOR]

The instability of all-inorganic perovskite nanocrystals (NCs) remains a major challenge to their practical applications in displays and lighting. In order to improve their environmental resistance, highly luminescent CsPbBr3 NC embedded Cs4PbBr6 microcrystals (MCs) have been fabricated by an anti-solvent reprecipitation method with the assistance of 1-alkyl-3-methyl-imidazolium bromides. The heterostructure of the MCs is investigated in detail, and their formation mechanism is discussed in terms of the dissolution–precipitation equilibria and the total energy of variously scaled nanoparticles via density functional theory (DFT) calculations. Although the imidazolium ligands are not directly capping with the inner CsPbBr3 NCs, they are important to the formation of these MCs. The MCs exhibit better thermal resistance compared to conventional CsPbBr3 NCs prepared by the hot-injection method. Additionally, a prototype white light-emitting diode (WLED) was fabricated to demonstrate its practical application prospects. Thanks to the narrow emission bands and enhanced stability of the MCs, the WLED shows greater performance compared to bare perovskite NCs, indicating its great potential as a green phosphor in lighting and display applications. [ABSTRACT FROM AUTHOR]

A new series of multicomponent compounds containing the cation [Co(NH3)6]3+ and various organic N-, N,O-, and O-donor moieties has been synthesized and crystallized. The series involves [Co(NH3)6]Cl3·2(phen)·3H2O (1), [Co(NH3)6](Hbdc)(bdc)·3H2O (2), [Co(NH3)6]Cl2(Hpht)·3H2O (3), [Co(NH3)6]Cl(Hpht)2·3H2O (4), [Co(NH3)6]Cl(2,3-pdc)·H2O (5), [Co(NH3)6]11[Co(2,5-pdc)3]8Cl·84H2O (6), [Co(NH3)6][Co(3,5-pdc)2(H2O)4]Cl·3H2O (7), [Co(NH3)6]Cl(sb)·4H2O (8), and [Co(NH3)6]2(sb)3·EtOH·2.5H2O (9) (where phen = 1,10-phenanthroline, H2bdc = diphenyl-4,4′-dicarboxylic acid, H2pht = o-phthalic acid, H2pdc = 2,3-/2,5-/3,5-pyridinedicarboxylic acid, H2sb = 4-sulfobenzoic acid). Single crystal X-ray diffraction studies have revealed that in these compounds the [Co(NH3)6]3+ cation serves as a building block for the incorporation of various anions/molecules and promotes the formation of multicomponent compounds with extended charge-supported networks between cations and anions and others such as H-bonds between charged⋯neutral and neutral⋯neutral components as well as π–π stacking interactions. In addition to the [Co(NH3)6]3+ cations, compounds 1–9 contain in changing composition Cl−, deprotonated phthalate, diphenyldicarboxylate, pyridinedicarboxylate, and sulfonate anions or complex [Co(2,5-pdc)3]4− and [Co(3,5-pdc)2(H2O)4]2− anions, as well as neutral 1,10-phenanthroline and ethanol and water molecules as components of the crystallization. Hirshfeld surface analysis was also performed to discuss the strength of hydrogen bonds and to quantify the inter-contacts. Energy decomposition analysis of the intermolecular interaction energy was performed using the SAPT method to study the non-covalent bonding interactions of [Co(NH3)6]3+ cations with mono-, dianions and neutral molecules, and it was found that the calculated bonding energy for compound 1 is minimal. Compounds 1–9 were tested in vitro against Rhizobium (Agrobacterium) vitis, an oncogenic bacterium that causes tumor formation in plants. Compound 1, comprising hexaammine cobalt(III) chloride and 1,10-phenanthroline, showed the highest inhibitory potential and is thus qualified for an application against bacterial cancer in plants. [ABSTRACT FROM AUTHOR]

European Committee for Standardisation (CEN) Technical Committee 264 'Air Quality' has recently produced a standard method for the measurements of anions and cations in PM 2.5 within its Working Group 34 in response to the requirements of European Directive 2008/50/EC. It is expected that this method will be used in future by all Member States making measurements of the ionic content of PM 2.5 . This paper details the results of a field measurement campaign and the statistical analysis performed to validate this method, assess its uncertainty and define its working range to provide clarity and confidence in the underpinning science for future users of the method. The statistical analysis showed that, except for the lowest range of concentrations, the expanded combined uncertainty is expected to be below 30% at the 95% confidence interval for all ions except Cl - . However, if the analysis is carried out on the lower concentrations found at rural sites the uncertainty can be in excess of 50% for Cl - , Na + , K + , Mg 2+ and Ca 2+ . An estimation of the detection limit for all ions was also calculated and found to be 0.03 μg m -3 or below.

A novel porous anionic MOF, [H2N(CH3)2][KZn2(bpyp)(dcba)2]·DMF·1.5H2O (Me2NH2@MOF-1), having exchangeable cations in 1D channels, has been synthesized and characterized. Specifically, the anionic MOF was shown to be able to serve as both a host and an antenna for protecting and sensitizing extra-framework light-emitting Eu3+/Tb3+ ions aqueously encapsulated within the MOF pores. Furthermore, the Tb3+ uptake and release was found to be a reversible process and the cationic Tb3+ can be gradually released. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) including novel superbase-derived ILs and imidazolium-based ILs with the potential to be used as green solvents for biomass utilization should be deeply evaluated with respect to their corrosion ability towards metallic equipment in industrialization. Herein, the corrosion susceptibility of 304SS in [DBUH][CH3CH2OCH2COO] was investigated for the first time and compared with that in common [EMIM][Ac] and [AMIM][Cl] by electrochemical, surface, and theoretical analyses. [DBUH][CH3CH2OCH2COO] exhibited an unprecedentedly excellent corrosion inhibition for 304SS compared to imidazolium-based ILs. This may be due to the presence of electron-donating carboxylate anions and macrocyclic superbase cations, which reacted with metals to form a compact layer and protected metals from damage. [EMIM][Ac] showed a slightly unfavorable corrosion inhibition compared to [DBUH][CH3CH2OCH2COO]. However, the corrosion rate of 304SS was dramatically increased in [AMIM][Cl] by increasing the temperature and water contents, which was reflected by pitting corrosion with plenty of pits (5–10 μm in diameter) on the 304SS surface after a polarization test. By studying the corrosion behaviour of five common steels in [DBUH][CH3CH2OCH2COO] and taking economy into consideration, 304SS with high Rct (26.69 × 105 Ω cm2) and Rp values (1230.8 Ω cm2) was the top priority for industrial equipment materials. According to the possible corrosion mechanism of metals in ILs from the viewpoint of DFT calculations and complex physico-chemical interactions, carboxylate ILs displaying outstandingly low contributions to corrosion particularly involving superbase cations or imidazolium cations and carboxylate anions with electron-donating groups such as –OCH2CH3, –OCH3, and –HC＝CH2 should be designed to mitigate corrosion damage in industrialized operations. [ABSTRACT FROM AUTHOR]

The post-synthetic exchange (PSE) method is a well-proven route to replace, modify, and add different functionalities to metal–organic frameworks (MOFs). Particularly, the solvent-assisted cation substitution (SACS) technique has been reported to prepare mixed-metal multivariate metal–organic frameworks (MTV-MOFs). However, such a technique does not apply to all types of MOFs. In 2013, Szilágyi et al. reported the achievement of the mixed-metal MTV-MIL-101 framework via PSE. Since then, a debate has been taking place about the validity of these findings. On the other hand, the attainment of the mixed-metal MIL-101 was reported to be obtainable through the direct synthesis, which is, to some, the only way to achieve it. Here, we settle this dispute by investigating Szilágyi's method not only as described, but also at extended conditions of time and different metal precursors: all attempts were vain. However, by reconsidering the refluxing solvent (dimethylformamide "DMF" instead of water) and the applied reaction conditions (110 °C–20 h), mixed-metal MIL-101(Cr/Fe) was achieved via a simple PSE method. [ABSTRACT FROM AUTHOR]