Molecular complexes can be used as electrocatalysts for oxygen reduction, water oxidation, and/or hydrogen peroxide production. However, in situ degradation of these catalyst is a major issue. This... Show moreMolecular complexes can be used as electrocatalysts for oxygen reduction, water oxidation, and/or hydrogen peroxide production. However, in situ degradation of these catalyst is a major issue. This dissertations describes the analysis of degradation processes as well as the performance of various molecular electrocatalysts. In addition, complexes have been structurally modified to perform structure-activity studies that could to mechanistic insight. In addition, it is described how molecular catalysts can be beneficial to heterogeneous electrocatalysis as well. Show less
The primary goal of this thesis is to study the potential role of electrochemistry in finding new routes for sustainable chemicals from biomass in aqueous-phase solutions. In order to assess the... Show moreThe primary goal of this thesis is to study the potential role of electrochemistry in finding new routes for sustainable chemicals from biomass in aqueous-phase solutions. In order to assess the potential of electrochemistry in biomass conversion, we developed an online HPLC system by using a fraction collector with a micrometer-sized sampling tip placed close to the working electrode, with the collected sample fractions subsequently analyzed in an offline HPLC system. To demonstrate this method, we applied it to the poly-ols, i.e. glycerol (C3H8O3), electro-oxidation on Au and Pt electrodes at different pH conditions, visualizing the concentration changes of glycerol and its reaction products in correspondence with the current measured in voltammetry, which brought us a concept to co-generate hydrogen and valuable chemicals (i.e. glyceraldehyde, glyceric acid, dihydroxyacetone, formic acid) with high selectivity depending on the applied potential. In addition, we aimed at single-cell synthesis of sorbitol from cellulosic material by generating glucose as an intermediate species. This thesis has demonstrated the separate reactions of cellobiose hydrolysis to glucose by acid and hydroxyl radical on an anode and glucose hydrogenation to sorbitol on a cathode in an electrolysis cell. Show less
