Probing the Interfacial behavior of nanostructured electrocatalysts for environmentally relevant catalytic systems

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Development and viability of important renewable energy technologies are inextricably linked to the electrochemical performance of their related catalytical materials. The composition of an electrocatalyst's surface and its atomic structure have a crucial influence on its performance characteristics, i.e. its catalytic activity and reaction selectivity. The fundamental understanding of catalytic processes is as meaningful for society as the search for new materials necessary for the commercialization of electrochemical device as alternative energy systems. In both cases, electrochemistry continues to play a pivotal role. Of various catalytic processes examined on electroactive materials, carbon dioxide reduction reaction (CRR) is a relevant processes with environmental applications and can be excellent candidate to be used as model systems for testing new electrodes. The proposed research program is focus on initiating a study of the kinetics and mechanism of those redox processes at nanostructured alloys, modified surfaces and well-defined surfaces for the elucidation and the understanding of the interfacial and electrochemical phenomena involved in electrocatalytic processes (adsorption phenomena, electrodeposition and nucleation). We proposed to modify the surface state selectively to study its role in the nature of the reaction intermediates and products. By the proper choice of the nature and stoechiometry of the participant metal in the electrocatalysts, it is possible to design substrate with various adsorption capability, mobility and structural geometry to inhibit or control the side reactions and to enhance the process efficiency. The research program is focusing on the role of the “ensemble-effect” and the nature of the interface metal-electrolyte, namely for CRR and ORR, two relevant electrochemical reactions. New CO2 conversion systems will be explore with solvents such as room temperature ionic liquids as well as with conventional aqueous media. In order to understand the impact of surface modifications and surface structure on the electrochemical activity and selectivity of (in)organic molecules, the reaction mechanisms and products will be investigate using on-line Electrochemical Mass Spectrometry and Rotating ring-disk Electrodes as complementary techniques. In-situ X-ray Absorption Spectroscopy will also be explore as a powerful technique to study surfaces of the designed electrocatalysts . Technologically, this research aims to provide results that will, on the short or long term, leads towards a better fundamental understanding of bifunctionnality of active materials and, ultimately, should lead to improved electrocatalysts for energy conversion and environmental applications.