Functionalization And Electrochemical Characterization Of Micro- And Nanoparticles For Applications In Catalysis And Electrochemiluminescence

Electrochemiluminescence (ECL) is an analytical technique where chemiluminescence is obtained through the electrochemical generation of a very reactive species at an electrode surface. ECL, which triggers optical signal by electrochemical reactions, offers the advantages of simplified optical setup, versatile utilization, high signal-to-noise ratio, and good temporal and spatial control. Therefore, it has been widely used in the field of immunoassays, food and water analyses, and for the detection of toxic agents.The original purpose of this thesis work is to develop a new series of ruthenium complexes for further application such as the imaging of micro-objects modified with the newly synthesized complexes. In our group, the synthesis of a new ligand pyta (pyridyl-1,2,3-triazole) opened a versatile route for the design ruthenium complexes that we wanted to test for ECL measurements. We aimed at modifying polystyrene beads with Ru-pyta complexes as a first step in the ECL imaging of living cells. However, the original selected polystyrene microbeads were found not suitable for efficient adsorption and/or covalent attachement of Ru-complexes,and we switched to the use of conductive carbon-coated cobalt carbide 50-nm nanoparticles (C/Co-NPs) in order increase the specific area and the electro-active complex molecule numbers connected with the electrode. Preliminary experiments showed that those beads could be a very efficient water oxidation catalyst and we chose to further develop this aspect.The manuscript of this thesis is organized in the following way:In chapter one, we present an overview of ECL and the application of Ru-pyta complexes. First, the characterizations of Ru-pyta complexes in solution are described; then, the ruthenium complexes and Os(bpy)32+ adsorption on polystyrene micro-objects are discussed.In the second chapter, we report a methodology to use carbon-coated cobalt carbide nanoparticles (C/Co-NPs) for the electrodeposition of amorphous metal oxide water oxidation catalysts onto an electrode. In this method, the metallic magnetic nanoparticles are contacted on the surface of an electrode with a magnet and then anodically corroded in the presence of electrolyte phosphate buffer. This result is a fast and efficient formation of an amorphous catalytic film. The advantage of the method lies in producing a catalytic film in a fast and efficient way.The thesis will be divided into two chapters independently; each chapter has its own introduction, contents and own references.