Electrocatalysis at liquid/liquid interfaces

摘要: This thesis is devoted to the study of oxygen reduction reaction catalysed by porphyrins at interface between two immiscible electrolyte solutions (ITIES). Electrochemical and spectrophotometric techniques are introduced these interfaces in order gather more information about transfer mechanism. Furthermore, oxidation decamethylferrocene (DMFc) 1,2-DCE production hydrogen peroxide (H2O2) aqueous phase, on basis two-phase controlled a common ion investigated. Mass spectrometric measurements were carried out for phase before after with an containing acid indicate stability DMFc DMFc+ over course reaction. Density function theory (DFT) computations have been performed based developed pathway. Catalytic effect 5,10,15,20-tetraphenylporphyrinatocobalt(II) [Co(tpp)], 2,3,7,8,12,13,17,18-Octaethyl-porphyrin cobalt(II) (CoOEP) free-base 5,10,15,20-meso-tetraphenylporphyrin (H2TPP) 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin (H2OEP) investigated as catalyst electron O2 presence donor various pH values polarized water|1,2-DCE interface. Using voltammetry, it possible drive this catalytic applied potential difference, where protons organic donors combine reduce O2. The signal observed corresponds proton-coupled (PCET) reaction, no current can be absence either catalyst, or [Co(tpp)] CoOEP catalysis work like conventional cobalt porphyrins, activating via coordination formation superoxide structure. advantages present system that, controlling interfacial proton from water accurately controlled. Accordingly, driving force reactions also effectively harnessed. Assisted (APT) studied across facilitated such H2TPP H2OEP. At interface, di-acid H4TPP2+ H4OEP2+ ion-transfer voltammetry UV-Visible spectroscopy, due double protonation H2OEP tertiary nitrogens ring. Additionally, "Ionic Partition Diagram" neutral ionisable compounds plotted illustrate contributions H2TPP.