Thèses en cours

Doctoral candidate : Clara MONGELLI
Thesis title : Design of Bifunctional Zeolite/Metal Catalysts for Redox Catalysis
Doctoral Advisor : Jean-Louis PAILLAUD
Supervisors : Emmanuel OHEIX

Abstract : Zeolites are inorganic, microporous, crystalline materials mainly composed of silicon and aluminum oxides. These materials are identified and classified according to their crystalline structure, and to date more than 250 different topologies have been reported. The presence of nanometer-sized pores enables the adsorption of small molecules, allowing for numerous applications in catalytic processes and separation technologies for the chemical industry, as well as in molecular decontamination. However, zeolites do not possess intrinsic redox properties. Therefore, the incorporation of metallic species can effectively complement their characteristics. Several methods are available to introduce metals into zeolites. Depending on the technique used, the amount, location, distribution, and nature of the metallic sites can vary significantly, thereby strongly influencing the properties and reactivity of the resulting materials. The aim of this project is to develop new hybrid materials (zeolite/metal systems) and to evaluate their catalytic activity in a reduction process for biomass valorization. The doctoral work includes the hydrothermal synthesis of zeolites, their functionalization with suitable metals, catalyst characterization at the different stages of preparation, and catalytic testing within the framework of a collaborative project.

Doctoral candidate : Thi Thuy Dung NGUYEN
Thesis title : Semiconductor perovskite nanocrystals confined in micro- and mesoporous matrices for CO2 photoreduction
Doctoral advisor : Andrey RYZHIKOV

Abstract : The thesis topic is part of the ANR EncaPer project, which will be carried out in collaboration with the Molecular Systems and Nanomaterials for Energy and Health Laboratory (SyMMES) in Grenoble and the Institute of Chemistry and Processes for Energy, Environment, and Health (ICPEES) in Strasbourg. It focuses on the synthesis of halogenated perovskite clusters and nanoparticles encapsulated in micro- and mesoporous matrices. The halogenated perovskites AMX3 and A3M2X9 (A+ is a monovalent inorganic or organic cation : Cs+, Rb+, methylammonium [CH3NH3]+, M is a divalent or trivalent metal cation such as Pb2+, Sn2+, Bi3+, and X is a halide anion I-, Br-, or Cl-) are a new class of inexpensive, efficient, and easily implemented semiconductor materials for photovoltaics, light emission, and photocatalysis. The nanocrystals of these materials are of particular interest due to the quantum confinement effect, which can influence their optoelectronic properties. The production of nanocrystals or clusters confined in micro- and mesoporous matrices such as zeolites and silicas with controlled morphology and pore size in the range of 0.5 to 10 nm is of great interest. This confinement should improve the stability of nanocrystals and enable the study of the effect of their shape and dimensions on their optical, electronic, and photocatalytic properties.

Doctoral candidate : Elena-Adelina RADUCAN
Thesis title : Development of Novel Hydrophobic ZIF-Type Materials for Energy Storage and Separation
Doctoral Advisor : Sylvie FERLAY, Aziz JOUATI (CMC)
Supervisors : Gérald CHAPLAIS (IS2M)

Abstract : Hybrid organic–inorganic materials of the ZIF (Zeolitic Imidazolate Framework) type generally exhibit (i) a high specific surface area, typically significantly higher than that of zeolites and porous silicas ; (ii) high thermal stability (300–600 °C), often exceeding that of other types of metal–organic frameworks ; and (iii) acceptable tolerance to high pressures, enabling their use across a wide range of applications. Within the framework of this collaborative PhD project between two research laboratories in the Alsace region, new series of fluorinated ligands will be synthesized on a large scale using conventional and “green” synthesis methods. These organic molecules will then be incorporated into new, highly hydrophobic ZIF-type hybrid phases. The structure–property relationships of these crystalline and porous architectures will be investigated in order to identify the most promising candidates for use in innovative mechanical energy storage and separation devices.

Doctoral candidate : Camille STUDER
Thesis title : Development of regenerable zeolitic adsorbent materials for the remediation of groundwater contaminated with oxygenated polycyclic aromatic compounds (O-PACs)
Doctoral co-advisor : Angélique SIMON-MASSERON
Supervisors  : Habiba NOUALI

Abstract : In industrialized countries, many soils are contaminated with polycyclic aromatic hydrocarbons (PAHs), which are toxic and carcinogenic compounds. Sixteen of these compounds, classified as priority pollutants by the US Environmental Protection Agency (EPA), are monitored due to their toxicity and frequent occurrence. However, other compounds, oxygenated polycyclic aromatic compounds (O-PACs), which are produced in particular by the degradation of PAHs, also pose risks to health and the environment. More soluble than PAHs, O-PACs migrate more easily into groundwater, thereby spreading pollution. Some existing decontamination methods for removing PAHs, such as chemical oxidation or biodegradation, promote the formation of O-PACs. It is therefore essential to develop effective solutions to eliminate the latter. This thesis project aims to design an innovative and economically viable process to treat both PAHs and O-PACs in groundwater. The chosen strategy is based on the use of regenerable porous mineral adsorbents to trap these contaminants. This approach will enable the validation of a decontamination process, a key step before possible industrialization.

Résumé : La recherche de la matière noire et de la double décroissance beta sans émission du neutrino constitue une thématique de recherche prioritaire en physique nucléaire. La mise en évidence de leur signature expérimentale nécessite des détecteurs ultrasensibles, avec une maîtrise totale des bruits de fond altérant les mesures. Les détecteurs sont basés sur des cibles formées des gaz monoatomiques (xénon) liquéfiés. Cependant le radon, un gaz radioactif présent à l’état de trace dans la cible constitue une source importante de bruit de fond. Il apparaît alors essentiel de purifier la cible, constituée du xénon de toute trace de radon. La réactivité de ces deux gaz monoatomiques est très limitée et en plus, leurs dimensions atomiques sont très proches. La purification de la cible du radon s’avère alors être un véritable challenge. Dans le domaine de la séparation des gaz, certains matériaux microporeux, tels que les zéolithes ont montré un fort potentiel. Par conséquent, l’objectif de la thèse, dans le cadre du projet ANR Innovative mateRials for Extreme radoN capturE est d’optimiser les paramètres des zéolithes afin qu’ils adsorbent sélectivement le radon dans un mélange avec le xénon. Une combinaison pertinente de différents outils de simulation moléculaire sera déployée dans ce but.

Mots-clés : adsorption, simulation moléculaire, Monte Carlo, dynamique moléculaire, DFT, zéolithes, radon, xénon

Doctoral candidate : El Batoul ZERIFI
Thesis title : Study of the adsorption properties of radon, xenon, and their mixtures in microporous materials, combining different molecular simulation techniques and working closely with the experiment
Doctoral advisor : Jean-Louis Paillaud
Supervisors : Irena Déroche, Taylan ORS

Abstract : The search for dark matter and double beta decay without neutrino emission is a priority research topic in nuclear physics. Detecting their experimental signature requires ultra-sensitive detectors with total control over background noise that can interfere with measurements. The detectors are based on targets formed from liquefied monoatomic gases (xenon). However, radon, a radioactive gas present in trace amounts in the target, is a significant source of background noise. It is therefore essential to purify the xenon target of all traces of radon. The reactivity of these two monoatomic gases is very limited and, in addition, their atomic dimensions are very similar. Purifying the target of radon therefore proves to be a real challenge. In the field of gas separation, certain microporous materials, such as zeolites, have shown great potential. Consequently, the objective of the thesis, as part of the ANR Innovative mateRials for Extreme radoN capturE project, is to optimize the parameters of zeolites so that they selectively adsorb radon in a mixture with xenon. A relevant combination of different molecular simulation tools will be deployed for this purpose. Keywords : adsorption, molecular simulation, Monte Carlo, molecular dynamics, DFT, zeolites, radon, xenon