We have synthesized a series of polystyrene-block-poly(4-vinylpyridine)s (PS-b-PVP) to which luminescent tricarbonyl(2,2‘-bipyridyl)rhenium(I) complexes were attached. The rhenium complexes could induce the self-assembly of the copolymers into nanosized micelles with different shapes and dimensions, depending on the block size distribution of the copolymers and the solvent system being used. In general, spherical micelles were observed when methanol, a nonsolvent for the polystyrene block, was added to a copolymer solution in dichloromethane. Micellization was observed when the added methanol concentration was approximately 30%. When toluene, a nonsolvent for the poly(4-vinylpyridine) block, was added to the copolymer solution in dichloromethane, micelles with different interesting shapes were observed. For copolymers with larger PVP block size, spherical micelles were observed. When the relative block size of the PVP block was reduced, the micelles gradually changed to disk or vesicle structures and then to rodlike structures. The rhenium complex can act as a luminescent probe in the resulting nanosized micelles and provide sufficient contrast for electron microscopic studies. Significant changes in luminescence spectra were observed after the micellization.

Multilayer polymer films composed of a ruthenium terpyridine complex containing poly(p-phenylenevinylene) (Ru-PPV) and sulfonated polyaniline (SPAN) were prepared by a layer-by-layer electrostatic self-assembly deposition. The deposition process was carried out from SPAN solution in water and Ru-PPV in dimethylformamide (DMF). Optical-quality multilayer thin films were obtained. The film growth process was monitored by quartz crystal microbalance, and the surface morphology of the films was studied by atomic force microscopy. It was found that the properties of the multilayer films were dependent on deposition conditions such as the pH of the SPAN solution, the presence of salt in the polymer solutions, and the post-film-forming thermal annealing process. Cross-section transmission electron microscopic images suggested that there was no stratified structure formed in the multilayer films. Photovoltaic cells were fabricated by sandwiching the multilayer films between indium-tin-oxide and aluminum electrodes. The device performances were examined by illumination with AM 1.5 simulated solar light. The power conversion efficiencies of these devices were on the order of 10(-3)%. The maximum incident photon-to-electron conversion efficiency (IPCE) of the devices was found to be approximately 2% at 510 nm, which is consistent with the absorption maximum of the ruthenium complex. This indicates that the photosensitization process is due to the electronic excitation of the ruthenium complex.

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