Design, synthesis and investigation of the photosensitive properties of mesoporous titania powders and donor-acceptor chromophores

The experimental work performed during this thesis was devoted to the design, synthesis and characterisation of photosensitive materials. On one side, synthesis of mesoporous titania powders through EISA method was performed. The influence of synthetic conditions (precursors type and molar ratio, ligand addition, calcination rates and temperatures, water addition and surfactant type) on both structural (phase composition and crystallite size) and morphological (surface areas, pore distribution and size) parameters were evaluated by X-Ray Powder Diffraction, N2 Physisorption measurements and Transmission Electron Microscopy. The materials were also tested as photoanodes in the water splitting reaction and the results compared to Degussa P25 as standard. On the other hand, synthesis, electrochemical and optical characterization of novel D-π-A dyes were performed. All the compounds obtained in each synthetic step were characterised in the same way, thus allowing to study the influence of the introduction of donor or acceptor fragments on a bithiophene backbone. Almost all the synthesised compounds were electropolymerised. The corresponding conducting polymers, which can be regarded as polymer dyes, were characterised by cyclic voltammetry and UV-Vis spectrophotometry