This work investigates the structural, magnetic and magneto-optical properties of a new zinc phosphate-tellurite glass belonging to the 45ZnO-10Al2O3-40P2O5-5TeO2 system. The glass was prepared by a wet method of processing the starting reagents followed by suitable melting–stirring–quenching–annealing steps. Specific parameters such as density, average molecular mass, molar volume, oxygen packaging density, refractive index, molar refractivity, electronic polarizability, reflection loss, optical transmission, band gap and optical basicity have been reported together with thermal, magnetic and magneto-optical characteristics. Absorption bands appear in the blue and red visible region, while over 600 nm the glass becomes more transparent. FTIR and Raman spectra evidenced phosphate-tellurite vibration modes proving the P2O5 and TeO2 network forming role. Magnetic measurements reveal the diamagnetic character of the Te-doped glass with an additional weak ferromagnetic signal, specific to diluted ferromagnetic oxides. Positive Faraday rotation angle with monotonous decreasing value at increasing wavelength was evidenced from magneto-optical measurements. The final product is a composite material comprising of a non-crystalline vitreous phase and Te-based nanoclusters accompanied by oxygen vacancies. The metallic-like Te colloids are responsible for the dark reddish color of the glass whereas the accompanying oxygen vacancies might be responsible for the weak ferromagnetic signal persisting up to room temperature.

Meteorites contain organic matter that may have contributed to the origin of life on Earth. Carbonyl compounds such as aldehydes and carboxylic acids, which occur in meteorites, may be precursors of biologically necessary organic materials in the solar system. Therefore, such organic matter is of astrobiological importance and their detection and characterization can contribute to the understanding of the early solar system as well as the origin of life. Most organic matter is typically sub-micrometer in size, and organic nanoglobules are even smaller (50–300 nm). Novel analytical techniques with nanoscale spatial resolution are required to detect and characterize organic matter within extraterrestrial materials. Most techniques require powdered samples, consume the material, and lose petrographic context of organics. Here, we report the detection of nanoglobular aldehyde and carboxylic acids in a highly primitive carbonaceous chondrite (DOM 08006) with ~ 20 nm spatial resolution using nano-FTIR spectroscopy. Such organic matter is found within the matrix of DOM 08006 and is typically 50–300 nm in size. We also show petrographic context and nanoscale morphologic/topographic features of the organic matter. Our results indicate that prebiotic carbonyl nanoglobules can form in a less aqueous and relatively elevated temperature-environment (220–230 °C) in a carbonaceous parent body.

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IV-VI semiconductor quantum dots embedded into an inorganic matrix represent nanostructured composite materials with potential application in temperature sensor systems. This study explores the optical, structural, and morphological properties of a novel PbS quantum dots (QDs)-doped inorganic thin film belonging to the Al2O3-SiO2-P2O5 system. The film was synthesized by the sol-gel method, spin coating technique, starting from a precursor solution deposited on a glass substrate in a multilayer process, followed by drying of each deposited layer. Crystalline PbS QDs embedded in the inorganic vitreous host matrix formed a nanocomposite material. Specific investigations such as X-ray diffraction (XRD), optical absorbance in the ultraviolet (UV)-visible (Vis)-near infrared (NIR) domain, NIR luminescence, Raman spectroscopy, scanning electron microscopy–energy dispersive X-ray (SEM-EDX), and atomic force microscopy (AFM) were used to obtain a comprehensive characterization of the deposited film. The dimensions of the PbS nanocrystallite phase were corroborated by XRD, SEM-EDX, and AFM results. The luminescence band from 1400 nm follows the luminescence peak of the precursor solution and that of the dopant solution. The emission of the PbS-doped film in the NIR domain is a premise for potential application in temperature sensing systems.

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