New boron-rich sulfide B6S and selenide B6Se have been discovered by combination of high pressure – high temperature synthesis and ab initio evolutionary crystal structure prediction, and studied by synchrotron X-ray diffraction and Raman spectroscopy at ambient conditions. As it follows from Rietveld refinement of powder X-ray diffraction data, both chalcogenides have orthorhombic symmetry and belong to Pmna space group. All experimentally observed Raman bands have been attributed to the theoretically calculated phonon modes, and the mode assignment has been performed. Prediction of mechanical properties (hardness and elastic moduli) of new boron-rich chalcogenides has been made using ab initio calculations, and both compounds were found to be members of a family of hard phases.

Raman spectra of rhombohedral boron monosulfide (r-BS)

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Quasi-hydrostatic compression of rhombohedral boron monosulfide (r-BS) has been studied up to 50 GPa at room temperature using diamond-anvil cells and angle-dispersive synchrotron X-ray diffraction. A fit of the experimental P-V data to the Vinet equation of state yields bulk modulus B0 of 42.2(1.4) GPa and its first pressure derivative B0′ of 7.6(2) that are in excellent agreement with our ab initio calculations. Formation of a new high-pressure phase of boron monosulfide (hp-BS) has been observed above 35 GPa. According to ab initio evolutionary crystal structure predictions combined with Rietveld refinement of high-pressure X-ray diffraction data, the structure of hp-BS has trigonal symmetry and belongs to the space group P-3m1. As it follows from electron density of states calculations, the phase transformation is accompanied by an insulator-metal transition.

Microcapsules loaded with n-docosane as phase change material (mPCMs) for thermal energy storage with a phase change transition temperature in the range of 36–45 °C have been employed to impregnate cotton fabrics. Fabrics impregnated with 8 wt % of mPCMs provided 11 °C of temperature buffering effect during heating. On the cooling step, impregnated fabrics demonstrated 6 °C temperature increase for over 100 cycles of switching on/off of the heating source. Similar thermoregulating performance was observed for impregnated fabrics stored for 4 years (1500 days) at room temperature. Temperature buffering effect increased to 14 °C during heating cycle and temperature increase effect reached 9 °C during cooling cycle in the aged fabric composites. Both effects remained stable in aged fabrics for more than 100 heating/cooling cycles. Our study demonstrates high potential use of the microencapsulated n-docosane for thermal management applications, including high-technical textiles, footwear materials, and building thermoregulating covers and paints with high potential for commercial applications.

New highly efficient heterogeneous catalysts based on an immobilized Anderson-type polyoxometalate supported on the functionalized SBA-15 surface have been successfully synthesized and characterized by FT-IR, XRD, N 2 adsorption−desorption isotherms, BET, SEM, TEM, EDX, and XPS analyses. The catalytic activity was investigated in the aerobic oxidative desulfurization of a model fuel. Heterogeneous catalysts were synthesized by various methods of immobilization using organic fragments of different natures. An efficient method of immobilization based on the grafting of N-methylimidazole as a cation-forming agent has been shown. The effect of temperature, dosage, and active phase loading on the conversion of dibenzothiophene (DBT) was studied. The highest activity was shown by the CoMo-0.5IL-SBA catalyst (IL = 1-methyl-3-(trimethoxysilylpropyl)-imidazolium cation), in the presence of which 100% DBT removal is achieved within 90 min at 120 °C at a catalyst amount of 0.2 wt %. Moreover, the immobilized catalyst could be recycled 5 times without a significant loss of catalytic activity.

Oxidative desulfurization is a promising method to produce clean fuels with an ultralow sulfur content at mild conditions. Herein, for the first time, we present multifunctional ionic liquid catalysts immobilized on mesoporous SBA-15 for highly efficient oxidation of dibenzothiophene. A combination of two active catalytic sites (phosphomolybdic acid fragment and carboxylic group) allows us to achieve complete oxidation of the most intractable dibenzothiophene to the corresponding sulfone in 5 min at 80 °C and H 2 O 2 /S = 6:1 molar ratio. The support and catalyst structures were investigated by low-temperature nitrogen adsorption/ desorption, Fourier transform infrared spectroscopy, X-ray fluorescence analysis, CHN analysis, and transmission electron microscopy techniques. Nicotinic acid fragments, bonded with the support and phosphomolybdic acid anion via covalent and ionic bonds, respectively, prevent active site leaching, thus retaining the catalyst activity for at least 10 reaction runs with preliminary regeneration. These catalysts are considered as promising systems for clean fuel production.

New boron subnitride B50N2 has been synthesized by crystallization from the B-BN melt at 5 GPa, and its structure has been refined using Rietveld analysis. B50N2 crystallizes in the tetragonal space group P-4n2 with unit cell parameters a = 8.8181(2) A and c = 5.0427(10) A. Quasi-hydrostatic compression of two boron subnitrides, B50N2 and B13N2, has been studied to 30 GPa at room temperature in a diamond-anvil cell using synchrotron X-ray diffraction. No pressure-induced phase transitions have been observed. A fit of experimental p-V data to the Murnaghan equation of state yielded B50N2 and B13N2 bulk moduli of 167(2) and 205(2) GPa, respectively, with fixed first bulk modulus pressure derivative of 4.0