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[Display omitted] • Slow evaporation synthesis method at room temperature of (C 6 H 7 N 2 S)NO 3. • Hybrid nitrate salt of 4-pyridinethioamide with a supramolecular crystal structure. • A good thermal stability for a wide range of temperatures. Organic-inorganic hybrid nitrate salt associating the aromatic organic molecule 4-pyridinethioamide with the (C 6 H 7 N 2 S)NO 3 formula was synthesized by slow evaporation method at room temperature. The obtained material is crystallized in the monoclinic system with the centro-symmetric space group P 2 1 / c. The supramolecular crystal structure was built from nitrate anions N O 3 - entities linked to the organic cations (C 6 H 7 N 2 S)+ by hydrogen bonds and weak interactions. Besides, the aromatic pyridinium rings of 4-pyridinethioamide molecules were proven to form chains through π...π interactions. The Hirshfeld analysis results have shown that in all potential molecular contacts, the H...O/O...H constitutes the most important interaction in the crystal with a contribution percentage of 39 %. The thermal behavior studied by thermogravimetric analyses revealed good stability up to 175 °C. Preliminary analyses recorded with infrared and Raman spectroscopy confirmed the existence of vibrational modes corresponding to the formation of the hybrid compound before performing the characterization by X-ray single-crystal diffraction. The optical absorption spectrum exhibits two bands located at 4.82 eV (257 nm) and 3.95 eV (314 nm), which can be even observed with the naked eye at room temperature and is due to exaction emission. [ABSTRACT FROM AUTHOR]

Cu 1.8 S has received a lot of interest as a prospective thermoelectric material with the best performance and abundant resources. While high charge carrier concentration contributes to the high electrical conductivity and power factor values, grain-boundary engineering is required to improve the phonon scattering and thermal stability of Cu 1.8 S. We used a simple process that combined nanoparticles via mechanical alloying and post-annealing to introduce the reduced graphene oxide (rGO) heterointerface into the Cu 1.8 S matrix. A significant enhancement of power factor has been realized that the highest power factor is 721 μWm−1 K−2 at 550 K in the composite Cu 1.8 S/rGO with 10 % rGO, which is higher than the pure Cu 1.8 S. Furthermore, following four cycles of testing from ambient temperature to 550 K, the composite demonstrated excellent repeatability of power factor, confirming its practical application potential. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Single-phase MgFe 2 O 4 nanoparticles (crystallite size ∼ 27 nm) were synthesized via citrate precursor route. • Saturation magnetization increased from ∼ 26.46 emu/g (300 K) to ∼ 34.79 emu/g (100 K). • Low coercivity (92–187 Oe) from 300 K to 100 K indicated soft magnetic behavior. • Observed remanent magnetization of ∼ 5.58 emu/g and remanence ratio of 0.21 at 300 K. • Blocking temperature estimated at ∼ 573 K, coercivity at 0 K at ∼ 249 Oe, and Curie temperature at ∼ 660 K. Low temperature magnetization measurements of citrate precursor-synthesized magnesium ferrite nanoparticles (MFNPs) of ∼ 27 nm were conducted by progressively lowering the temperature from 300 K to 100 K. Hysteresis curves revealed unsaturated magnetization even at ± 15 kOe, attributed to surface spins. Specific saturation magnetization (σ s) and coercivity (H c) experienced an increase from 26.46 emu/g (300 K) to 34.79 emu/g (100 K), and from 92 Oe (300 K) to 187 Oe (100 K), respectively. Specific remanence magnetization (σ r) rose from 5.58 emu/g (300 K) to 10.14 emu/g (100 K), indicating a notable shift in magnetic behavior. Effective anisotropy constant (K eff) showed significant growth from 2474.14 erg/g (300 K) to 6635.04 erg/g (100 K), highlighting low magnetocrystalline anisotropy at room temperature. The rise in magnetic moment (n B) from 0.95 Am2 at 300 K to 1.25 Am2 at 100 K indicates improved magnetic alignment and stability, particularly at lower temperatures. Correlation analysis revealed strong negative curvilinear correlations between magnetic properties and temperature. Extrapolation estimated the blocking temperature (∼573 K), coercivity at 0 K (∼249 Oe), and Curie temperature (∼660 K). These results suggest promising applications in space technology, underscoring the enhanced sensitivity of MFNPs to external magnetic fields in cold environments. [ABSTRACT FROM AUTHOR]

• New oxyfluoroniobate glasses were synthesized in the ZnNbOF 5 -BaF 2 -InF 3 system. • The thermal properties of the obtained glasses are determined. • The structures of the glass networks in the system studied are revealed. • Glasses in the ZnNbOF 5 -BaF 2 -InF 3 system show luminescence was properties. • In glasses with luminescent properties, nano-objects 9–13 nm in size were found. Glasses in the ZnNbOF 5 –BaF 2 –InF 3 and ZnNbOF 5 -BaF 2 systems were produced using the ZnNbOF 5 •6H 2 O compound. The structure, thermal and luminescent properties of the obtained glasses were studied with IR-, Raman, SAXS, luminescent spectroscopy methods, calorimetry and X-ray diffraction. The highest range of thermal stability and resistance of glass to crystallization has been established for the glass of 20ZnNbOF 5 –40BaF 2 –40InF 3 composition. This value is an order of magnitude higher than in glasses of the same system, but not containing InF 3. Glasses networks are formed from polyhedra of InF 6 , NbO 2 F 4 and NbO 3 F 3. For all glasses containing InF 3 , photoluminescence contribution which depends on the concentration of indium trifluoride in the glass was recorded. This contribution corresponds to the emission levels of 542, 573, 673, 751 nm. Luminescent properties are shown by glasses in which nanoobjects (nanoinhomogeneities) in size of 9-13 nm were detected by SAXS method. [ABSTRACT FROM AUTHOR]