Superconducting low dimensional systems are the natural choice for fast and sensitive infrared detection, because of their quantum nature and the low-noise, cryogenic operation environment. On the other hand, monochromatic and coherent electron beams, emitted from superconductors and carbon-based nanostructured materials, respectively, are significant for the development of electron optical systems such as electron microscopes and electron-beam nanofabrication systems. Here we describe for the first time a simple method which yields carbon nanotubes encapsulating single crystalline superconducting tin nanowires by employing the catalytic chemical vapor deposition method over solid tin dioxide. The superconducting tin nanowires, with diameters 15-35 nm, are covered with well-graphitized carbon walls and show, due to their reduced diameters, a critical magnetic field (Hc) more than 30 times higher than the value of bulk metallic tin.

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Magnetic Fe(2)O(3)/carbon hybrids were prepared in a two-step process. First, acetic acid vapor interacted with iron cations dispersed on the surface of a nanocasted ordered mesoporous carbon (CMK-3). In the second step, the primarily created iron acetate species underwent pyrolysis and transformed to magnetic iron oxide nanoparticles. X-ray diffraction, Fourier-transform infrared, and Raman spectroscopies were used for the chemical and structural characterization of the hybrids, while surface area measurements, thermal analysis, and transmission electron microscopy were employed to determine their physical, surface, and textural properties. These results revealed the preservation of the host carbon structure, which was homogenously and controllably loaded (up to 27 wt %) with nanosized (ca. 20 nm) iron oxides inside the mesoporous system. Mössbauer spectroscopy and magnetic measurements at low temperatures confirmed the formation of γ-Fe(2)O(3) nanoparticles exhibiting superparamagnetic behavior. The kinetic studies showed a rapid removal of Cr(VI) ions from the aqueous solutions in the presence of these magnetic mesoporous hybrids and a considerably increased adsorption capacity per unit mass of sorbent in comparison to that of pristine CMK-3 carbon. The results also indicate highly pH-dependent sorption efficiency of the hybrids, whereas their kinetics was described by a pseudo-second-order kinetic model. Taking into account the simplicity of the synthetic procedure and possibility of magnetic separation of hybrids with immobilized pollutant, the developed mesoporous nanomaterials have quite real potential for applications in water treatment technologies.

Li2SnS3 is a fast Li+ ion conductor that exhibits high thermal stability (mp ∼750 °C) as well as environmental stability under ambient conditions. Polycrystalline Li2SnS3 was synthesized using high-temperature, solid-state synthesis. According to single-crystal X-ray diffraction, Li2SnS3 has a sodium chloride-like structure (space group C2/c), a result supported by synchrotron X-ray powder diffraction and 119Sn Mössbauer spectroscopy. According to impedance spectroscopy, Li2SnS3 exhibits Li+ ion conductivity up to 1.6 × 10–3 S/cm at 100 °C, which is among the highest for ternary chalcogenides. First-principles simulations of Li2SnS3 and the oxide analogue, Li2SnO3, provide insight into the basic properties and mechanisms of the ionic conduction. The high thermal stability, significant lithium ion conductivity, and environmental stability make Li2SnS3 a promising new solid-state electrolyte for lithium ion batteries.

Room temperature ferromagnetism is found in (Sn 1Ϫx M x)O 2 (M ϭMn, Fe, Co, xϭ0.05) ceramics where x-ray diffraction confirms the formation of a rutile-structure phase. Room temperature saturation magnetization of 0.2 and 1.8 Am 2 kg Ϫ1 for (Sn 0.95 Mn 0.05)O 2 and (Sn 0.95 Fe 0.05)O 2 , respectively, corresponds to a moment of 0.11 or 0.95 B per Mn or Fe atom. The Curie temperatures are 340 and 360 K, respectively. The magnetization cannot be attributed to any identified impurity phase. 57 Fe Mössbauer spectra of the Fe-doped SnO 2 samples, recorded at room temperature and 16 K, show that about 85% of the iron is in a magnetically ordered high spin Fe 3ϩ state, the remainder being paramagnetic.