StatusThe thesis was presented on the 4 September, 2015
Approved by NCAA on the 7 October, 2015
Abstract– 2.67 Mb / in romanian
– 2.55 Mb / in english
8.55 Mb /
Thesis consists of introduction, four chapters, overall conclusions and recommendations, bibliography of 223 references and 14 annexes comprising of 24 figures. 128 pages of main text contain 90 figures, 11 tables and two equations. The results described within this dissertation were published in 13 scientific papers: four articles in journals with impactfactor and one in journal of B grade (without co-authors), part of a chapter from international book, one oral and seven poster presentations (three without co-authors) at scientific conferences.
The aim of this work is the study of structure-property relationships that would allow a better understanding of the mechanisms governing the photophysical and electrochemical processes, in the porphyrin and ferrocene based systems, in order to identify their practical potential. A variety of contemporary methods, including IR, NMR and mass spectrometries, atomic absorption, elemental and X-ray diffraction analyses, were used for molecular composition and structural characterisation of the compounds, while UV-Vis absorption and spectroelectrochemistry, pump-probe transient absorption, Mössbauer spectrometry, cyclic voltammetry and DFT molecular modelling were employed in order to study the photophysical, electrochemical and applicative properties.
The originality of results. 14 new derivatives of ferrocene and porphyrin were obtained using elaborated synthetic protocols and the reaction mechanisms were proposed. It should be emphasized the synthesis of the new, rarely isolated ketopyrrole halfway product in the BODIPY synthesis, and its BF2 chelate, as well as the novel simple route for oxidative desymmetrization of ferrocene molecule. For the first time a ferrocene-porphyrin dye was employed as sensitizer for TiO2 surface in a Grätzel cell and the key processes governing the system efficiency were analysed. The mechanism for Pd(II) and Cu(II) porphyrin ring centred electrochemical hydrogen production was proposed consi-sting of a phlorin mediated pathway and a feasible explanation of ferrocene units role was suggested.
This work is giving some answers and conclusions with fundamental and applicative value, that are expected to be useful in the further research both in our and other teams working in similar or related area. The simple chromatography-free method elaborated for desymmetrizing ferrocene molecule is an alternative route to 1,1'-asymmetrical ferrocenes that could find practical applications in industrial catalytic processes. The cyclic voltammetry of bis-ketopyrrolic derivative of ferrocene proved the material to be useful for nucleophiles redox sensing. The study of photoinduced processes in ferrocene-porphyrin dye anchored on the TiO2 surface is a trial to find the “bottleneck” of DSSCs and the conclusions made within this work will guide further design of porphyrin-sensitized solar cells. The meso-tetraferrocenyl porphyrin metal complexes showed catalytic activity in electrochemical generation of molecular hydrogen, giving some valuable information for generation of alternative materials for the electrocatalytic reduction of protons.
The solved scientific problem consists of elucidating the structure-property relationship in the molecular systems based on ferrocene/porphyrin, contributing to a deeper understanding of the physical and chemical processes in the materials studied for further optimisation of their practical efficiency.
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