Post-doc: How the Composition and Microstructure of High-Entropy Alloys Influence Their Hydrogen Sorption Properties (M/F)

Job Description

Missions

This postdoctoral contract will be conducted as part of the SolHyd project within the PEPR-H2 (Priority Research Program and Equipment for Decarbonized Hydrogen). The PEPR-H2 aims to develop decarbonized hydrogen as an essential vector for the future energy mix by supporting upstream research on all relevant topics for the emergence of a high-performance and sustainable hydrogen sector (low-carbon hydrogen production, new storage solutions for heavy mobility applications, etc.).

The postdoctoral researcher will focus on a recent and highly promising class of materials for reversible solid-state hydrogen storage: high-entropy alloys (HEAs). These multi-element compounds consist of at least 4–5 chemical elements, leading to high mixing entropy that promotes the formation of simple crystalline solid solutions (bcc, fcc, hcp). HEAs exhibit particularly interesting hydrogen sorption properties (fast kinetics, high reversible storage capacities, equilibrium plateaus compatible with applications such as electrolyzers and fuel cells), which can be modulated by the choice of constituent elements. This selection is based on the ability of a given element to form hydrides more or less easily, as expressed by the enthalpy of hydride formation. Combining elements with a strong affinity for hydrogen (Ti, V, Mg, Zr, Nb, Ta, etc.) with elements having a weaker affinity (Cr, Mn, Fe, Ni, Zn, etc.) allows the hydrogen sorption properties of HEAs to be tailored. The candidate will study new alloy compositions identified as promising, building on previous work conducted within our team (two PhD theses on the subject) and in collaboration with other SolHyd project teams contributing to the field, particularly through supervised machine learning predictions and thermodynamic calculations.

Activity

This postdoctoral project aims to link the chemical composition (present phases and their respective stoichiometries), crystalline structure, and microstructure of alloys with their hydrogen sorption properties. For a given alloy composition, the candidate will explore ways to modify these parameters, particularly through various heat treatments (annealing, quenching, or hyper-quenching) and severe plastic deformation (forging). A wide range of synthesis and characterization methods will be available: induction or arc melting, X-ray diffraction (XRD), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX), volumetric measurements using the Sieverts method for hydrogen sorption properties. Additional methods may be considered, such as EBSD, in situ XRD at large-scale facilities (synchrotron at ESRF and neutron diffraction at the Institut Laue-Langevin), to describe structural changes during absorption and desorption processes. A detailed exploration of these materials will enable optimization of their properties and a deeper fundamental understanding of hydrogen affinity in these disordered structures.

Your Profil

Skills

The candidate must have a strong background in materials science. The proposed work will be primarily experimental, so organizational skills, rigor, data analysis, and synthesis will be key evaluation criteria. Strong written and oral communication skills are also expected.

Your Work Environment

The candidate will work within the Materials, Radiation, and Structure (MRS) team at the Institut Néel. He will collaborate with L. Laversenne, P. de Rango and A. Bailly and will benefit from the support of the laboratory's technical teams. They may also collaborate with other scientists in the PEPR-H2.

The Institut Néel is a CNRS unit (UPR 2940) under agreement with the University Grenoble Alpes. The laboratory is related to the CNRS Physique. It is located in Grenoble, in the heart of a unique scientific, industrial and cultural environment. It is one of the largest French national research institutes for fundamental research in condensed matter physics enriched by interdisciplinary activities at the interfaces with chemistry, engineering and biology. It consists of 450 employees, including 175 researchers.
CNRS is a public, scientific and technological organisation.
The core mandate is to identify, carry out ou have carried out, either alone or with partners, all research that advances science or contributes to the country's economic, social, and cultural progress. Internationally recognised for the excellence of its scientific research, the CNRS is a reference in the world of research and development, as well as for the general public.

Compensation and benefits

Compensation

Between 3041,58 € and 3467,33 € gross monthly according to experience

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

The research professions