UNamur: Laboratoire d’analyse par Réactions Nucléaires (LARN)

General expertise of the research group

The research and teaching activities fold up around (1) Materials sciences, (2) Ion-Matter interactions and (3) Life sciences.

LARN is a research laboratory at UNamur, comprising 28 individuals (3 Professors, 5 post-docs, 13 PhDs, 3 Engineers, 3 technicians, 1 secretary), divided into two research areas: Materials Science and Biophysics, the latter not being related to this project.

LARN has extensive expertise in the deposition of high-performance thin films by vacuum method (physical vapor deposition). Over the past ten years, numerous projects (FEDER, SPW, M-ERANET, etc.) have enabled the development of unique know-how in the deposition of thin films via low-pressure plasma, using state-of-the-art equipment (vacuum deposition chamber, high-specificity plasma generator, characterization methods). Understanding the growth modes and physico-chemical properties of films, with the aim of maximizing the performance of these surfaces, is at the core of LARN’s research activities. The targeted applications encompass the fields of engineering, optics, the medical sector, and the mechanical sector. These aspects are developed both experimentally with exceptional equipment and through simulation, thanks to the development of the NASCAM calculation code. This code allows for the determination of the growth and properties of films deposited by Monte Carlo method and is used by research centers as well as industries (approximately 700 licenses). In 2017, the spin-off Innovative Coating Solutions S.A. has been created based on the experience of the laboratory.

LARN also benefits from access to the SIAM platform (Synthesis, Irradiation, and Materials Analysis), which has state-of-the-art characterization equipment and recognized scientific expertise in materials analysis. Among its range of characterization techniques, we will particularly mention ion beam analyses, which have the unique ability to quantify the hydrogen concentration profile in materials without requiring sample destruction. Since its establishment in September 2016, the SIAM platform’s objectives are to support research within UNamur on one hand, and to offer its expertise in materials characterization to the industrial world on the other hand. The scientific staff of the platform is thus involved in daily interactions with both young scientists in their research and experienced industrial partners dealing with various challenges

The study of ion-matter interactions is the second topic in fundamental and applied research. Nuclear reactions which occur in the heart of stars (in the CNO cycle for instance) are the same as those used for materials analysis. Not only the efficient nuclear reactions mesure sections involved in astrophysics but also the knowledge about incident ions stopping section are of interest for materials analysis. Moreover, nuclear and atomic analysis techniques are improved and tested daily to better answer the growing needs of research and industry for surfaces and interfaces characterization.

Finally, the laboratory puts all the acquired knowledge in the two aforementioned topics to the service of life sciences. The multidisciplinary team studies cell response to photon or particle irradiation theoretically as well as experimentally.

Specific hydrogen- related expertise & research topics

• LARN and SIAM have been at the forefront of an industrial project aimed at evaluating the degradation of mechanical performance in various metallic materials subjected to very high hydrogen fluxes. This SMART project itself followed another project funded by the company IBA to study the performance of lithium targets under very high hydrogen fluxes. In both cases, the UNamur particle accelerator (LARN/SIAM) is used to implant hydrogen into the material being characterized. This ion implantation technique allows for precise control over the quantity and depth at which hydrogen is introduced into the material. Furthermore, this technique enables the achievement of hydrogen concentrations in materials much more rapidly than through more conventional methods (e.g., exposing the material to a high-pressure and/or high-temperature hydrogen atmosphere).
• The same particle accelerator is then used to perform ion beam analyses to determine the concentration profile of the implanted hydrogen. Since this analysis is non-destructive, it can be repeated after various sample treatments (e.g., temperature changes, corrosion, mechanical stresses), allowing the study of how hydrogen behaves in a given material based on its environmental conditions.
• Regarding coating activities, LARN was involved in the development of coating for bipolar plates of fuel cells and electrolyzers in funded projects (INOXYPEM project), but also directly in relation with renowned actors (Siemens Energy, Borit, ZBT). The development of new plasma product/process in relation to energy production and storage is at the heart of LARN activities, in addition to the scaling and validation of new plasma couples/processes developed by Unamur in relation to energy production and storage.

Available equipment/tools:

• 5 plasma deposition chambers with different types of discharges (DC, HiPIMS, RF, Bipolar, etc.), enabling deposits through PVD and PECVD (Physical Vapor Deposition and Plasma Enhancement Chemical Vapor Deposition) methods, including plasma diagnostic techniques (probes, emission spectroscopy, in-situ stress measurement, etc.).
• Mechanical characterization equipment (nanoindenter, tribometer, profilometer, Rockwell).
• ALTAÏS accelerator for ion implantation and ion beam analysis, including hydrogen quantification.
• 2 XPSspectrometers with ion or cluster profiling capabilities.
• ToF-SIMSspectrometer.
• Access toX-ray Diffraction (DRX), Scanning Electron Microscopy (SEM), SEM Energy Dispersive Spectroscopy (EDS), Transmission Electron Microscopy (TEM), and TEM-EDS measurements at UNamur.

This extensive range of equipment and capabilities at LARN and SIAM enables comprehensive research and analysis in various material science and characterization fields, making them valuable resources for both scientific research and industrial applications.

Participating in FL/B/EU funded projects with H2 related research:

• INOXYPEM FEDER Plasmanode (M-eranet) (energy/production storage) Win4Ex TiNTHyN
• Submitted project (not granted): Win²Wal PLASCOLYZE FTE COP-E FEDER StorHywall

Main relevant publications

1. E. Haye, F. Deschamps, G. Caldarella, M.-L. Piedboeuf, A. Lafort, H. Cornil, J.-F. Colomer, J.-J. Pireaux, N. Job, Formable chromium nitride coatings for proton exchange membrane fuel cell stainless steel bipolar plates, International Journal of Hydrogen Energy. 45 (2020) 15358–15365. https://doi.org/10.1016/j.ijhydene.2020.03.248.
2. S. Lucas, E. HAYE, J.-J. Pireaux, Tunable multifunctional carbon-based coatings, WO2022084519A1, 2022. (accessed August 18, 2022). https://patents.google.com/patent/WO2022084519A1/en
3. A. Costa, F. Ferreira, J.L. Colaux, et al., “Effect of hydrogen incorporation on the mechanical properties of DLC films deposited by HiPIMS in DOMS mode”, Surface and Coatings Technology (2023) 129980. https://doi.org/10.1016/j.surfcoat.2023.129980
4. M. Michiels, A. Hemberg, T. Godfroid, et al., “On the relationship between the plasma characteristics, the microstructure and the optical properties of reactively sputtered TiO2 thin films”, Journal of Physics D: Applied Physics 54 (2021). DOI: 10.1088/1361-6463/ac118e