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Alloying of perovskites nanocrystals by lanthanoids makes it possible to produce materials that luminesce effectively in both visible and near infrared spectra. In the present work, the influence of the width of the forbidden zone on the optical properties of the inorganic perovskites nanocrystals CsPbClxBr3-x alloyed by ions Yb3+ is investigated. For changing the chemical composition of nanocrystals, an anionic exchange method is used by adding bromide dodecyltrimethylammonium. As a result of the gradual substitution of chlorine ions with bromine ions, the forbidden area of nanocrystals is narrowed, resulting in a change in the spectral position of the optical transitions, the quantum output of photoluminescence in the near and infrared spectral ranges and the attenuation of photoluminescence. When the width of the forbidden area reaches 2.54 eV, the total quantum output of photoluminescence reaches 72%. Keywords: pervoskite nanocrystals, alloying, ytterbium, photoluminescence, anionic exchange.

Semiconductor 2D nanostructures are a new platform for the creation of modern optoelectronic devices. Layered 2D PbSe-MoS2 nanostructures with efficient photoinduced charge transfer from PbSe nanoplatelets (NPLs) to MoS2 were created. When PbSe NPLs with short organic ligands are deposited onto a thin layer of MoS2 NPLs, a decrease in their photoluminescence intensity and a decrease in the average photoluminescence lifetime are observed. When a layered 2D PbSe-MoS2 nanostructure is illuminated with IR radiation, a photocurrent appears, which indicates the contribution of PbSe NPLs to the electrical response of the system. Ultrathin layers of transition metal dichalcogenides sensitized with nanostructures based on lead chalcogenides can be used in photodetectors with a spectral sensitivity region extended to the near-IR range. Keywords: nanoplatelets, transition metal dichalcogenides, charge transfer, near infrared region.

© 2017, Pleiades Publishing, Ltd.An effective procedure for the preparation of imines based on 4-methyl-4-diphenylphosphorylpentan-2-one, aminoacetic, aminopropionic, and aminobutyric acids with yields of 90–95% was developed. Reaction of dimephosphone (4-methyl-4-dimethoxyphosphorilpentan-2-one) with potassium salts of these amino acids led to methylation of the carboxy group of the amino acid to form potassium salt of 2-methyl-4-oxopentylphosphonic acid methyl ester.

© 2016 Elsevier LtdA new two-step synthesis of phosphonium salts from phosphine oxides using Grignard reagents is reported. This approach involves a cyclization of Z-dialkyl-(diaryl)[2-(5-chloro-2-hydroxyphenyl)-2-phenylvinyl]phosphine oxides under the action of sulfinyl chloride with the formation of 2,2-dialkyl(diaryl)-6-chloro-4-phenyl-2H-1,2-benzoxaphosphinin-2-ium chlorides followed by ring opening under the action of organomagnesium compounds. The method was successfully applied to prepare a series of a new phosphonium salts bearing phenolic moiety with a wide range of substituents at phosphorus atom. Synthesized phosphonium salts shows high antibacterial and antifungal in vitro activity and low toxicity towards human red blood cell.

© 2015 Springer Science+Business Media New York. [Figure not available: see fulltext.] A Pfitzinger reaction of isatin with 2-methyl-(4-oxopent-2-yl)dialkyl(diphenyl)phosphine oxides was used to synthesize new derivatives of 4-quinolinecarboxylic acids, containing a phosphine oxide fragment, and screening for antimicrobial activity was performed.

Copyright © 2015 Taylor & Francis Group, LLC. A new two-step method for obtaining of phosphonium salts from phosphine oxides was developed. The method includes a cyclization of the dialkyl-2-(2-hydroxy-5-chlorophenyl)-2-phenylethenylphosphine oxides caused by sulfinyl chloride followed by the ring opening under the action of Grignard reagent.

© 2014 Elsevier B.V. The present work introduces a novel route to sense the permeability of the polyelectrolyte layer deposited onto luminescent core. The use of ternary Eu(III) complexes as the luminescent core enables to detect the permeability of the polyelectrolyte layers through the change of the Eu(III)-centered luminescence. The chelating anions, such as adenosine phosphates, glutamic acid and ethylenediaminetetraacetic acid disodium salt were used as substrates. The origin of the fluorescent response is the complex formation of the substrates with the Eu(III) complexes, which is greatly affected by the equilibrium concentration of the substrates at the surface of the core. The latter in turn is influenced by the permeability of the polyelectrolyte layer. The obtained results highlight the impact of the nature of the exterior layer in the penetration of the substrates through the negatively and positively charged polyelectrolyte layers.

The present report is inspired by the idea to develop novel spectroscopy based techniques to detect the phase transitions in solutions of triblock copolymers with the use of Gd(III) and Eu(III) ions as probes. The choice of (PEO)13(PPO)30(PEO)13 (L64), (PPO)14(PEO)24(PPO)14 (17R4), (PPO)8(PEO)22(PPO)8 (10R5) and Triton X-100 is conditioned by their phase transitions occurring in mild conditions. The cloud point extraction (CPE) data reveal the conditions (pH and chelating agent) where the binding of lanthanides with surfactant rich phase of triblock copolymers and Triton X-100 occurs. The effect of phase transitions in solutions of triblock copolymers on the temperature resolved line widths in EPR spectra of Gd(III) aqua ions and transverse relaxation rates of Gd(III) inner-sphere water protons depends on the architecture of triblock copolymers and pH conditions. The steady state luminescence of Eu(III) complexes with phosphine oxide in aqueous solutions of triblock copolymers and TX-100 is influenced by the temperature induced aggregation and phase separation in solutions of reverse triblock copolymers 17R4 and 10R5, while the effect of the aggregation is insignificant for L64. © 2012 Elsevier B.V.

Four new compounds, asymmetrical phosphine oxides containing 2-hydroxyphenylethenyl fragment in cis-orientation with respect to the phosphine oxide: dibutyl-, diphenyl-, dibenzyl-, and dinaphthyl-2-(2-hydroxy-5- chlorophenyl)-2-phenyl-ethenylphospnine oxides, have been studied in aqueous ethanol (80 vol % of EtOH) by means of potentiometry and spectrophotometry at 25±0.1 C, and their acid-base and complexing properties estimated. © 2013 Pleiades Publishing, Ltd.

The present work introduces the determination of fluoroquinolone antibiotics (FQs) in aqueous solutions through the fluorescent response of Eu(TTA)3 and [Eu(TTA)31] (TTA- and 1 are thenoyltrifluoroacetonate and phosphine oxide derivative) complexes encapsulated into the polyelectrolyte capsules fabricated through layer-by-layer deposition of poly(sodium 4-styrenesulfonate) (PSS) and polyethyleneimine (PEI). The variation of luminescent core, polyelectrolyte deposition and concentration conditions reveals two modes of fluorescent response on FQs of diverse structure namely the sensitization and quenching of Eu(III) centered luminescence. The obtained regularities reveal the ternary complex formation and the ligand exchange occurring at the interface of polyelectrolyte coated [Eu(TTA)31] based colloids as the reasons of the diverse fluorescent response of Eu(III) centered luminescence on FQs. The factors affecting the fluorescent response have been revealed, which are: the content of luminescent core, the mode of polyelectrolyte deposition, concentration and structure of FQs. The discrimination of moxifloxacin and lomefloxacin from levofloxacin, ofloxacin, difloxacin, perfloxacin through the quenching of Eu(III) luminescence in PSS-[Eu(TTA)31] colloids has been revealed. © 2013 Elsevier B.V.