The proposed PhD is taking place in the general context of the development of hydrogen-powered electric vehicles and more specifically aims to improve the tools for modelling and characterizing polymer membranes used in Proton Exchange Membrane Fuel Cells (PEMFC). In this fuel cell technology, in addition to the anode and the cathode, which are the sites of the oxidation of hydrogen and the reduction of oxygen respectively, there is a solid electrolyte made up of a cation-conducting polymer which transfers hydrated protons between the two compartments of the cell.
The thesis aims to investigate the relationship between structure and reactivity of transition metal sulfide within lithium-sulfur batteries. Lithium-sulfur batteries have theoretically very important assets (specific energy three times higher than lithium-ion, low cost, low toxicity) yet they are penalized by some limitations. Among them, a strong redox shuttle, short lithium polysulfides that leads to self-discharge and severe capacity loss. Transition metal sulfides such as MoS2 are known to trap and catalyze the transformation of these lithium polysulfides.
Butadiene is a crucial chemical, notably for the manufacturing of elastomers and tires but currently is only produced from fossil sources. In the transition to the sustainable economy, the ethanol-to-butadiene reaction has emerged as a promising solution to secure its production but above all to limit its environmental footprint. As a result, it has gathered significant scientific interest and private companies are investigating its application. The development of dedicated catalysts for this reaction is therefore a priority area of research.