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Title

Σύνθεση της 5,10,15,20-tetrakis (4-carboxyphenyl)-porphyrin cobalt(II) και σύζευξή της με NC-Dots για φωτοκαταλυτική παραγωγή υδρογόνου

Alternative Title

Synthesis of the 5,10,15,20-tetrakis (4-carboxyphenyl)-porphyrin cobalt(II)) and coupling with NC-Dots for photocatalytic hydrogen generation

Author

Μερτζάνη, Στυλιανή

Thesis advisor

Κουτσολέλος, Αθανάσιος

Abstract

The rapid development of the modern world, has led to increased energy demands, the fulfilment of which mainly comes from the burning of fossil fuels. Fossil fuels are described as non-renewable sources and burning of fossil fuels leads to carbon dioxide emissions. Thus, the improvident use of fossil fuels led not only to the energy crisis, but to the environmental crisis as well. Therefore, the scientific world became interested in finding renewable sources, including which the solar energy stands out due to its abundance. Solar energy is very important, since it can be used by photocatalytic systems, for the generation of hydrogen. Nature was a great source of inspiration for this idea, since there are organisms that use solar energy and convert it into chemical energy in a biological path that is called photosynthesis. In addition, molecular hydrogen is a very promising type of fuel, since the element of hydrogen abundant and since its burning is clean and friendly for the environment, due to the fact that its only product is water. Photocatalytic systems that use solar energy consist of the photosensitizer (PS), the catalyst (CAT) and the sacrificial electron donor (SED). This bachelor thesis is about the implementation of such a photocatalytic system, through the synthesis of the porphyrin CoTCPP and the nanoparticles NC-Dots, that combine to form hybrids that will act both as photosensitizers and catalysts. Porphyrin CoTCPP, NC-Dots and hybrid NC-Dots- CoTCPP are characterized by various methods such as: matrix-assisted laser ionization (MADLI- TOF-MS), UV-Visible absorption spectroscopy (UV-Vis), fluorescence and nuclear magnetic resonance spectroscopy (NMR). Finally, photocatalytic experiments took place, in which samples of the hybrids and the NC-Dots alone are studied, in order to specify the importance of the porphyrin in the ability of the hybrids to act as photosensitizers. It was found that the porphyrin plays a significant role in the absorption of light by the photosensitizer, since the samples of the NC-Dots without the porphyrin didn’t generate hydrogen. Gas chromatography with a thermal conductivity detector (TCD) was used in order to measure the hydrogen generated by the samples.

Language

Greek

Subject

Energy crisis

Photocatalysis

Renewable energy sources

Solar energy

Ανανεώσιμες πηγές ενέργειας

Ενεργειακή κρίση

Ηλιακή ενέργεια

Πορφυρίνες

Φωτοκατάλυση