Doctorant(M/F):Advanced spectroscopic techniques for the characterization of Power to Ammonia catalysts

Job Description

Thesis Subject

Hydrogen (H2) is currently presented as a realistic energy carrier, but it suffers from a lack of long-term storage solutions. Ammonia (NH3) offers interesting advantages in terms of energy density and is considered as an alternative. The goal of the PEPR project CATANA-2 is to identify new catalysts for ammonia synthesis and ammonia decomposition. Within this project, we are seeking for a PhD candidate to develop In Situ and Operando characterization for the different catalysts that will be tested and modelled by the other partners. The goal is to access the structure of the different catalysts under real reaction conditions and to probe their electronic structure. Ultimately, a relationship between electronic structure of the catalysts and their performance in synthesis and/or cracking of ammonia would enable the design of new catalytic formulations.
Some of the characterization can be performed on laboratory scale experiments available at UCCS in Lille such as Laser Raman Spectroscopy, X-Ray Photoelectron Spectroscopy (XPS) as well as X-Ray Absorption Spectroscopy with our newly acquired Laboratory XAS spectrometer. Some more advanced techniques are available on the synchrotron light source SOLEIL. For example, Kβ XES can be used to elucidate electronic structure and spin state of transition metals and Valence-to-Core (VtC) transitions provide insight into valence bands of solids affording a precise electronic structure determination. Furthermore, High Energy Resolution Partial Fluorescence Detection XAS (HERPFD-XAS) allows to probe selectively metals with showing different oxidation state within a mixture. Finally X-Ray Raman Scattering (XRS) is a powerful thought barely used technique allowing to probe the environment of light elements with hard X-Ray and thus in Operando conditions.
All these advanced characterizations will first be used to characterize the catalysts used for the cracking of ammonia. These catalysts consist of 3d transitions metal (Fe, Co, Ni) supported on alumina or silica. The transition metal can be promoted by alkali metals (K, Cs). The transition metal is deposited on support through a simple impregnation in its stable oxide form. Depending on the nature of the dopants, the solid is activated under hydrogen/nitrogen mixture at adequate temperature. Then, the cracking reaction can start by replacing the H2/N2 flow by an ammonia flow. The different steps need to be monitored precisely and the exact role of dopants needs to be established. A clear picture of the structural and electronic properties of the different catalysts under reaction conditions will then be compared with the results obtained with DFT modelling at ICGM (Montpellier) and catalytic evaluation at UCEIV (ULCO).

Applicants should hold an MSc degree Chemistry, Physical Chemistry or Physics with a sound background in spectroscopy. Scientific rigor, autonomy, and good English writing skills are required.

Your Work Environment

Project within the frame of the « Programme et équipements prioritaires de recherche sur le développement de matériaux innovants par l'intelligence artificielle » (PEPR-DIADEM), our consortium (CNRS, Université de Lille, CEA, Université du Littoral-Côte d'Opale, Université de Montpellier, SOLEIL) launched a research project on the power to ammonia process. The work will be carried out primarily at the UCCS on the Cité Scientifique campus in Villeneuve d'Ascq. Short-term visits to SOLEIL are planned to fine-tune the experiments.

Compensation and benefits

Compensation

2300 € gross monthly

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

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