LiFe 1−y Mn y PO 4 /C nanofi ber composites are applied as cathode materials in Li-ion batteries and their electrochemical properties are explored. Nanofi ber meshes are synthesized via electrospinning of commercially available precursors (LiOH · H 2 O, FeSO 4 · 7H 2 O, MnSO 4 · H 2 O, H 3 PO 4 , and polyvinylpyrrolidone). Nanofi bers calcined at 850 ° C under Ar/H 2 (95/5 vol%) atmosphere are directly used as self-supporting electrodes in Swagelok half cells without the need for any conductive additive or polymer binder. The morphology, phase, and chemical composition of as-prepared and heat-treated samples are analyzed by means of X-ray powder diffraction, thermogravimetric analysis, and electron and scanning microscopy techniques. Brunauer-Emmett-Teller gas adsorption-desorption measurements show a high specifi c surface area (111m 2 g − 1 ) for LiFe 0.5 Mn 0.5 PO 4 . The infl uence of different Fe/Mn ratios on the morphology, electrical, and electrochemical performances are analyzed. 554 www.MaterialsViews.com www.advenergymat.de

An efficient synthesis of highly crystalline SnO(2) QDs with a narrow size distribution (4.27 +/- 0.67 nm) was achieved by microwave-assisted decomposition of Sn(OtBu)(4) in ionic liquid. Printed structures fabricated from SnO(2) QDs showed typical semiconducting I-V behaviors, and gas sensing properties.

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Hollow tin-oxide (SnO 2 ) nanospheres were synthesized by coating, carbon nanospheres (CNs) as hard templates, with a tin (IV) sol obtained by partial hydrolysis of [Sn(OBu t ) 4 ] under ambient conditions. Formation of crystalline SnO 2 spheres upon calcination was confirmed by powder X-ray diffraction data, whereas the hollow interiors of SnO 2 particles were verified by scanning and transmission electron microscopy of both intact and broken spheres. The shell of SnO 2 nanospheres sintered at 700°C consisted of a single layer of nanocrystallites (~6 nm) self-assembled in a ball-like superlattice. Tin-oxide hollow spheres showed an average diameter of 150 nm and could be homogeneously dispersed in water/ethylene glycol (50:50 vol%) mixture to form stable inorganic inks viable for their use in commercial ink-jet printers demonstrated by printing porous ceramic structures on an interdigitated sensor chip. The integration of large surface and nanoscopic voids in the final structures imparted higher sensitivity to the as-printed sensors toward both oxidizing (nitrogen dioxide) and reducing gases (methane and ethanol), which validates the enormous potential of printable inorganics in functional applications.

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Nanosized (20-30 nm) colloidal gold, silver and their alloys were obtained by reductive transformation of corresponding metal salts. Dispersions of metal nanoparticles (σ < 4%) in aqueous solutions were obtained by appropriate surface functionalization which led to inorganic inks with solid fraction ranging from 0.01-4%. Judicious choice of a polymer additive (polyethylene glycol or carboxymethyl cellulose) was found to be crucial to avoid the agglomeration of nanocrystals in the ink-jetted structures upon solvent evaporation. The versatility of the nanoparticle-based printing technology was demonstrated by fabrication of dot-matrices and circuitry patterns on different substrates. Characterization of printed structures showed a homogeneous topography (AFM) and uniform distribution of metallic nanoparticles (SEM/TEM) within the ink-jetted microdrops. The site-specific patterning on silicon (001) substrates with nanoparticle (mono)layers could also be achieved by printing the linker molecule, aminopropyltriethoxysilane, followed by selective attachment of gold nanoparticles. Positionally ordered and chemically bonded gold catalyst patterns were used for the chemical vapour deposition (CVD) of nanowires, which led to site-specific growth of nanowires via the vapour-liquid-solid (VLS) mechanism and unlike in the case of spin-coated metal colloids no significant lateral diffusion of metal nanoparticles was observed, in chemically anchored Au nanoparticles. Nanoparticle containing inks allow a user-defined dilution to vary the density of CVD grown nanowires, which was utilized to show the differences in catalytic activities of silver and gold catalysts in the VLS growth.