Inside Ceramics and Between MgO Grains: Solid-State Synthesis of Intergranular Semiconducting or Magnetic Spinels.

Configurations of composite metal oxide nanoparticles are typically far off their thermodynamic equilibrium state. As such they represent a versatile but so far overlooked source material for the intergranular solid-state chemistry inside ceramics. Here, it is demonstrated how the admixture of Fe and In ions to MgO nanoparticles, as achieved by flame spray pyrolysis, can be used to engage ion exsolution, phase separation, and subsequent spinel formation inside the network of diamagnetic and insulating MgO grains.

Bifunctional Fe(II) spin crossover-complexes based on ω-(1-tetrazol-1-yl) carboxylic acids.

To increase the supramolecular cooperativity in Fe(ii) spin crossover materials based on N1-substituted tetrazoles, a series of ω-(1H-tetrazol-1-yl) carboxylic acids with chain-lengths of C2-C4 were synthesized. Structural characterization confirmed the formation of a strong hydrogen-bond network, responsible for enhanced cooperativity in the materials and thus largely complete spin-state transitions for the ligands with chain lenghts of C2 and C4. To complement the structural and magnetic investigation, electronic spectroscopy was used to investigate the spin-state transition.

Identifying the reactive sites of hydrogen peroxide decomposition and hydroxyl radical formation on chrysotile asbestos surfaces.

Background: Fibrous chrysotile has been the most commonly applied asbestos mineral in a range of technical applications. However, it is toxic and carcinogenic upon inhalation. The chemical reactivity of chrysotile fiber surfaces contributes to its adverse health effects by catalyzing the formation of highly reactive hydroxyl radicals (HO) from HO.

Magnetic Characteristics of Ni-Filled Luminescent Porous Silicon.

The aim of the presented work is to combine luminescent porous silicon (PSi) with a ferromagnetic metal (Ni) to modify on the one hand the photoluminescence by the presence of metal deposits and on the other hand to influence the optical properties by an external magnetic field. The optical properties are investigated especially with respect to the wavelength-shift of the photoluminescence due to the metal filling. With increasing metal deposits within PSi the photoluminescence peak is blue-shifted and furthermore an increase of the intensity is observed.