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The spread of bacterial infections aggravated by the development of microbial resistance to antibiotics requires the creation of protective antibacterial materials. Nanomaterials with biocides can provide antibacterial and antibiofilm properties against Gram-positive and Gram-negative bacteria. In this work, we synthesized nanocomposites with silver nanoparticles and different polyoxometalates of Keggin-structure (phosphomolybdic, phosphotungstic, and tungstosilicic acids) on eco-friendly nanoclay called halloysite. We found that the nanocomposite containing silver nanoparticles and phosphomolybdic acid deposited on the halloysite possesses the best antibacterial performance of all the obtained composites, having a minimal inhibitory concentration of 0.5 g/L against S. aureus, 0.25 g/L against P. aeruginosa and A. baumannii. This composite reduces the viability of formed biofilms at a concentration of 2.5 g/L.

The molecular and crystal structures of the title compound, C8H4F5NO, were examined by single-crystal X-ray diffraction and Hirshfeld surface analysis. The title compound was synthesized by a new method at the interface of aqueous solutions of LiOH and pentafluorophenylacetonitrile. In the crystal, hydrogen bonds and π–halogen interactions connect the molecules into double layers. Analysis of the Hirshfeld surface showed that the most important contributions to the crystal packing are made by F...F (30.4%), C...F/F...C (22.9%), O...H/H...O (14.9%), H...F/F...H (14.0%) and H...H (10.2%) contacts. The Hirshfeld surfaces of analogues of the title compound were compared and the effect of perfluorination on the crystal packing was shown.

The extraction of lithium from aqueous solutions of LiNTf2 and LiCl salts using benzo-15-crown-5 ether (B15C5) as an extractant in [C8mim][NTf2] ionic liquid was studied. The transition of the extractant into the aqueous phase and the distribution of Cl− ions during lithium extraction from LiCl solutions were determined. LiNTf2 complexes with B15C5 with different LiNTf2:B15C5 ratios were isolated for the first time and characterized via X-ray diffraction and IR spectroscopy. Differences in the extraction process of LiCl and LiNTf2 were determined via an infrared spectroscopic study of the extraction systems.

It was established that isopropyl salicylate can be used similarly to 1,3-diketones as a key component for a new efficient extraction system for selective separation of alkali metal cations. According to DFT modeling of complexes of isopropyl salicylate and 1,3-diketone with alkali metal cations (Li+, Na+, K+), six-membered metallacycles are formed whose stability decreases along the series Li > Na > K, which results in the observed enhanced affinity to lithium. The extraction ability of isopropyl salicylate is manifested in the presence of trioctylphosphine oxide (TOPO). The newly obtained complexes of isopropyl salicylate with alkali metal cations as well as their extracts in a mixture with TOPO are characterized by means of FT-IR, Raman, and NMR spectroscopy. The probable structure of the extracted lithium complex is presumed and the role of TOPO in the extraction process is investigated in detail. Extraction experiments showed extremely high separation coefficients for Li/Na and Li/K pairs in the extraction from a model multi-component solution.