We report on a new and versatile method for preparing homogenous, crack-free and macro-meso-porous thick films of TiO 2 , ZnO and ZnO-TiO 2 composites using a single step coating procedure and fairly low annealing temperatures of a maximum of 400 1C. The method relies on an oxide nanopowder filler in an optimized precursor solution. The films are well adherent to the substrate, show homogeneously distributed open porosity, and are hydrophilic. The photocatalytic activity of these films was characterized using methyl orange as a model dye. We show that the TiO 2 films have better photocatalytic activity than ZnO and ZnO-TiO 2 composite films. The advantages of these composite films over particulate photocatalysts lie in their robustness and ease of application as no filtration is needed. Furthermore it is possible to apply them on suitable large area membranes.

A template-free sol-gel method for the synthesis of hierarchically nano-structured lithium-titaniumoxide films is proposed involving a p-type doping of titanium isopropoxide sols with lithium. The structures of the films are analyzed by scanning electron microscopy, X-ray powder diffraction and Raman spectroscopy. Different phases can be accessed by controlling the annealing temperature. Supersaturated anatase (Ti, Li)O 2 is formed at 400 C, whereas anatase and/or rutile interspersed with Li 2 TiO 3 and Li 4 Ti 5 O 12 are observed between 450 C and 800 C. The nanostructure formation is explained by a dissolution-crystallization-self-assembly mechanism.

The giant magnetoresistance (GMR) and structure was investigated for electrodeposited Co/Cu multilayers prepared by a conventional galvanostatic/potentiostatic pulse combination from a pure sulfate electrolyte with various layer thicknesses, total multilayer thickness and Cu deposition potential. X-ray diffraction (XRD) measurements revealed superlattice satellite reflections for many of the multilayers having sufficiently large thickness (at least 2 nm) of both constituent layers. The bilayer repeats derived from the positions of the visible superlattice reflections were typically 10 -20% higher than the nominal values. The observed GMR was found to be dominated by the multilayer-like ferromagnetic (FM) contribution even for multilayers without visible superlattice satellites. There was always also a modest superparamagnetic (SPM) contribution to the GMR and this term was the largest for multilayers with very thin (0.5 nm) magnetic layers containing apparently a small amount of magnetically decoupled SPM regions. No oscillatory GMR behavior with spacer thickness was observed at any magnetic layer thickness. The saturation of the coercivity as measured by the peak position of the MR(H) curves indicated a complete decoupling of magnetic layers for large spacer thicknesses. The GMR increased with total multilayer thickness which could be ascribed to an increasing SPM contribution to the GMR due to an increasing surface roughness, also indicated by the increasing coercivity. For multilayers with Cu layers deposited at more and more positive potentials, the GMR FM term increased and the GMR SPM term decreased. At the same time, a corresponding reduction of surface roughness measured with atomic force microscopy indicated an improvement of the multilayer structural quality which was, however, not accompanied by an increase of the superlattice reflection intensities. The present results underline that whereas the structural quality as characterized by the surface roughness generally correlates fairly well with the magnitude of the GMR, the microstructural features determining the amplitude of superlattice reflections apparently do not have a direct influence on the GMR. Due to the large giant magnetoresistance (GMR) effect observed in physically deposited Co/Cu multilayers, 1-3 a lot of efforts have been devoted to the study of GMR also on electrodeposited (ED) Co/Cu multilayers (for detailed references, see a recent review).4 A variety of baths have been used for the preparation of ED Co/Cu multilayers, 4 the simplest one containing merely CoSO 4 and CuSO 4 . Over the last two decades, numerous reports have been published on studying the GMR characteristics of ED Co/Cu multilayers from the pure sulfate bath (containing at most some buffering agents). [5][6][7][8][9][10][11][12][13][14][15] In this list of references, we have included only those works from the much larger number of reports 4 in which the ED Co/Cu multilayers were prepared from the sulfate bath at or close to the electrochemically optimized Cu depositi...

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In both title pyridine derivatives, (I) and (II), the cation adopts an E configuration with respect to the C=C. In compound (I), the PF6 − anion is disordered with occupancy factors of 0.614 (7):0.386 (7). In both the compounds, the crystal packing is stabilized by C—H⋯F inter­molecular inter­actions results into two-dimensional mol­ecular sheets, which are formed by (14) ring motifs in compound (I), (40) ring motifs in compound (II). In addition to that, the crystal packing is further stabilized by P—F⋯π inter­actions in compound (I) and π–π in compound (II).