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Iron phthalocyanine-coated hexagonal boron nitride (FePc/h-BN) nanoparticles, obtained by FePcCl adsorption on the h-BN surface from a dimethylformamide solution, were subjected to heat treatment in order to form single atom Fe1/h-BN catalysts. Samples were characterized by means of X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, scanning and transmission electron microscopy, and temperature-programmed oxidation/reduction/desorption. The FePc deposition process was optimized to avoid the formation of nanoparticles. FePc exhibits high thermal stability in a hydrogen atmosphere and decomposes into a single iron atom when oxidizing in an O2 flow at 350 °C (sample Fe1-ox/h-BN). Subsequent reductive heat treatment in hydrogen (sample Fe1-red/h-BN) results in the formation of Fe-based nanoparticles due to Fe1 diffusion and association, resulting in a decrease in catalytic activity. Hydrogenation proceeds according to the Eley–Rideal mechanism with CO2 chemisorption on the Fe1 surface species (Fe1-ox/h-BN) and is changed to the Langmuir–Hinshelwood mechanism (Fe1-red/h-BN). Selectivity for hydrocarbons increases after reduction of the Fe1-ox/h-BN sample. Our results open up new possibilities for using metal phthalocyanine as a precursor for cheap, reproducible, and efficient single atom catalysts for CO2 hydrogenation. [ABSTRACT FROM AUTHOR]

The results of detailed characterization of new antimicrobial materials in the form of Ce(NO3)3 × 6H2O salt with the proposed crystal-chemical composition of [Ce3+(H2O)4(NO3)3] × 2H2O and its aqueous solution by X-ray diffraction (XRD), differential scanning calorimetry (DSC), X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS) are presented. The stages of [Ce3+(H2O)4(NO3)3] × 2H2O thermal decomposition with the formation of [Ce3+(H2O)4(NO3)3] (<220 °C), Ce3+ONO3 (230–320 °C) and Ce4+O2 (>300 °C) are shown. It was found that Ce3+ ions in the composition of [Ce(H2O)4(NO3)3] × 2H2O salt and in its aqueous solution retain their formal charge (FC Ce = 3) and coordination number (CNCe = 10, where 6O from three NO3− groups and 4O from four 4H2O molecules) with the reorientation of nitro groups in Ce3+ far environment in an aqueous salt solution. It was established that [Ce3+(H2O)4(NO3)3] × 2H2O, [Ce3+(H2O)4(NO3)3] and Ce3+ONO3 salts inhibit the growth of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa bacteria in the absence of radiation with a growth zone inhibition diameter D > 37 mm with Dmax = 45 mm on the multiphase sample ([Ce3+(H2O)4(NO3)3], Ce3+ONO3, Ce4+O2), which is higher than that on penicillin (D = 12–18 mm). It is shown that an increase in the [Ce3+(H2O)4(NO3)3] × 2H2O salt concentration in an aqueous solution has a positive effect on antimicrobial activity. It is not excluded that the absence of interaction of Ce3+ ions in the salt solution with Langmuir phospholipid monolayers of phosphatidylethanolamine (DPPE) and phosphatidylglycerin (DPPG) is associated with the damage to the protein component of the bacterial membrane and not with the phospholipid one and/or with the "penetration" of Ce3+ ions into the cell and violation of its water-ionic balance. It is shown that the "H-Beta – Ce3+(NO3)3 × 6H2O" system fabrication with biocompatible H-Beta zeolite contributes to the preservation of antimicrobial activity in the dark (Pseudomonas aeruginosa) with a decrease in the amount of the active component. [ABSTRACT FROM AUTHOR]

Implantation and subsequent behaviour of heavy noble gases (Ar, Kr, and Xe) in few-layer graphene sheets and in nanodiamonds are studied both using computational methods and experimentally using X-ray absorption spectroscopy. X-ray absorption spectroscopy provides substantial support for Xe-vacancy (Xe-V) defects as main sites for Xe in nanodiamonds. It is shown that noble gases in thin graphene stacks distort the layers, forming bulges. The energy of an ion placed in between flat graphene sheets is notably lower than that in domains with high curvature. However, if the ion is trapped in the curved domain, considerable additional energy is required to displace it. This phenomenon is likely responsible for strong binding of noble gases implanted into disordered carbonaceous phase in meteorites (the Q-component). [ABSTRACT FROM AUTHOR]

Novel heteroleptic Er(III) and Yb(III) naphthalocyaninato-phthalocyaninates containing an octa-phenyl or octa-phenoxysubstituted naphthalocyanine deck were synthesised and identified by 1H NMR, EPR and high resolution MALDI-TOF/TOF mass spectrometry. Direct synthesis of novel homoleptic Yb(III) bis (octa-phenylnaphthalocyaninate) was carried out. Downfield lanthanide induced shifts of the aromatic protons in target compounds were observed compared with the corresponding diamagnetic Lu(III) complexes. In the near-IR absorption spectra, an increase in ionic radius from Lu(III) to Er(III) resulted in a bathochromic shift of the intervalence band up to 1473 nm. This work presents the first experimental EPR study of Yb(III) bis naphthalocyaninate, where a set of magnetic parameters and properties (including spin, magnitude and sign of magnetic anisotropy parameter D, increased splitting in a crystal field, ferromagnetic f–π interaction etc.) were determined and interpreted by both EPR and SQUID techniques and supported by theoretical considerations. [ABSTRACT FROM AUTHOR]