Sujet de stage / Master 2 Internship

The aim of the internship is to explore the potential of radiolysis as a screening method for reagent/catalyst couples, with a view to developing an energy-efficient chemistry with a lower carbon footprint.

In the context of the search for less polluting and more energy-efficient processes than current ones, it is interesting to produce high-stake molecules such as CH4, C2H4.... The manufacture of ethylene, a basic product of the polymer industry, requires the use of high pressures and/or high temperatures. Processes such as photocatalysis, which are based on the use of light energy, are therefore attractive. However, their efficiency is sometimes low, and it can take a long time to identify the best catalysts for a given reaction.

The NIMBE unit (CEA/Saclay) specializes in the synthesis of different types of nanostructures to meet societal challenges particularly in the energy and environment sectors. As part of its research activities, it is developing pure TiO2 nanoparticles or nanoparticles surface-modified with metals for photocatalysis. The efficiency of these nanoparticles has been tested in photocatalysis for ethylene production. The results depend on the nature of the metal used, its dispersion, the size of the nanoparticles, etc. In order to determine whether radiolysis, which relies on the use of ionizing radiation to create excited species, can be an effective method of screening catalysts, initial experiments have already been carried out on reagent/catalyst couples previously studied in photocatalysis. The first results are encouraging. The aim of this internship is to extend this work by preparing reagent/catalyst mixtures in sealed ampoules, then irradiating them and measuring the gases produced by gas-phase micro-chromatography, focusing specifically on ethylene.

The trainee's task will be to measure the various gases produced by irradiation of the reagent/catalyst pairs and compare them with the results obtained in photocatalysis. He/she will also be able to make proposals to extend the study to other catalysts or reagents, to measure other species of interest and to gain a detailed understanding of the processes involved.

The internship will take place at CEA-Saclay in the CEA-CNRS NIMBE Unit (Nanosciences and Innovation, Materials, Biomedicine and Energy).

Profile: Master 1, Master 2 Materials, physical chemistry
Rigor, curiosity, taste for experimentation, critical thinking.
Duration: 4-6 months (to be defined with the trainee's teaching institute)
Starting date: from February 2024, to be defined with the trainee's teaching institute.
Location: CEA Saclay, Saclay
Contacts: Nathalie Herlin-Boime : nathalie.herlin@cea.fr and Sophie Le Caër : sophie.le-caer@cea.fr