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Nanoscale oxide/polymer composites consisting of a silica core coated with either methylmethacrylate (MMA) or ethyl-2-cyanoacrylate (ECA) are produced in-situ by chemical vapor synthesis (CVS). In this process, a hot-wall reactor is used for the preparation of the oxide core, followed by a plasma reactor to form the polymer coating. Deposition of the coating material was confirmed using nitrogen adsorption, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), highresolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and thermal analysis (TGA). The influence of the monomer on the dispersability in polar and non-polar media was investigated by photon correlation spectroscopy (PCS).

Nanocrystalline Sm2O3 and Sm2O3–MgO powders have been prepared by spray pyrolysis of aqueous precursor solutions containing citric acid as a complexant. Synthesized powders consist of hollow spheres with thin shells. The two‐phase samples exhibit an improved microstructural stability compared with pure Sm2O3. The microstructure before and after various heat treatments has been investigated by high‐resolution transmission electron microscopy, scanning electron microscopy, nitrogen adsorption, and X‐ray diffraction.

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Artificial light-harvesting antennas consisting of self-assembled chromophores that mimic the natural pigments of photosynthetic bacteria have been inserted into voids induced in porous titania (TiO2, anatase) in order to investigate their suitability for hybrid solar cells. Mesoporous nanocrystalline TiO2 with additional uniform macropores was treated with precursor solutions of the pigment which was then induced to self-assemble within the voids. The chromophores were tailored to combine the self-assembly characteristics of the natural bacteriochlorophylls with the robustness of artificial Zn-porphyrins being stable for prolonged periods even upon heating to over 200 degrees C. They assemble on the TiO2 surface to form nano- to micro-crystalline structures with lengths from tens of nm up to several microm and show a photosensitization effect which is supposed to be dependent on the assembly size. The natural examples of these antennas are found in green sulfur bacteria which are able to use photosynthesis in deep water regions with minute light intensities. The implementation of biomimetic antennas for light harvesting and a better photon management may lead to a rise in efficiency of dye-sensitized solar cells also under low light illumination conditions.