Functional hybrids are nano-composite materials lying at the interface of organic and inorganic realms, combining properties and advantages of both materials, and possibly minimizing their disadvantages. Nanostructured titanium dioxide is one of the most investigated material for hybrid systems, as its application areas range from photovoltaics and photocatalysis to photo-/electrochromics, optoelectronics and sensors. Among organic molecules, metal-phthalocyanines (MPcs) are of particular interest due their great versatility and high thermal and chemical stability. A critical and very challenging issue in hybrid system engineering is the contemporary achievement of the metal oxide nano-crystals and the molecular sensitization process. As the high crystalline quality of TiO2 is commonly obtained through thermal treatments, its organic decoration is usually carried out in successive separate steps. Supersonic beams techniques (SuMBD) offer to overcome this challenge, thanks to the possibility of working with both organic molecules and inorganic aggregates, and to the ability to achieve physical and chemical processes at surfaces. The final aim of this thesis work is the study of the molecular sensitization processes, induced by supersonic beams approaches, occurring at the titanium dioxide/copper phthalocyanine interface.A preliminary extensive analysis of the nanostructured TiO2 thin films grown by PMCS is performed, in order to test the material peculiarities resulting from the non conventionality of the deposition technique. At the Parma IMEM-CNR Laboratories, the as-grown TiO2 thin films were investigated by means of several electron microscopy techniques. The morphological and luminescence properties have been evaluated by Scanning Electron Microscopy and Cathodoluminescence, while Transmission Electron Microscopy analyses provided the structural information. These studies have been integrated by surface photoelectron spectroscopies (XPS and UPS), that the candidate performed at the Trento IMEM-CNR Laboratories in order to study the material electronic properties. Moreover, the effects of annealing treatments on the observed properties have been investigated and discussed.Photoelectron emission experiments on both copper and free-base phthalocyanine, grown by SuMBD. These experiments have been carried out at synchrotron ELETTRA (Trieste). The aim of this study was to understand the real influence of the metal core on the molecule electronic properties.Taking advantages of the high resolution of the synchrotron facility, it was possible to determine well suitable fit models for both molecules. In particular, the deconvolution model related to the CuPc was decisive in the last part of this thesis work, to analyze the reactivity processes at the inorganic/organic interface.After achieving a comprehensive knowledge of the electronic properties of both the organic and the inorganic counterparts, we focused our attention to the chemical reactivity phenomena occurring at their interface, which is the final aim of this thesis work. In the Trento IMEM-CNR Laboratories, we got two hybrid systems with the same configuration (CuPc/TiO2) in a combined PMCS/SuMBD approach. In both cases the nanocrystalline metal oxide has been synthesized by PMCS, at room temperature without the need of any thermal treatment. In order to understand the role of the kinetic energy during the sensitization process, the CuPc deposition has been performed by molecular seeded beams at high (experiment A) and low (experiment B) kinetic energies. For both hybrid systems, a complete characterization of core levels and valence band states have been performed at increasing organic coverages, in order to better emphasize the dynamic of the chemical bonds formation at the interface, induced by different kinetic energies.
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