PhD Position (M/F): Recycling and Regeneration of Catalysts for Alkaline Water Electrolysers in Non-Conventional Solvents

Job Description

Thesis Subject

The energy transition requires the development of efficient and carbon-neutral technologies for energy storage and conversion. In this context, hydrogen (H2) is considered one of the most promising energy carriers. Ideally, hydrogen is produced by water electrolysis using intermittent renewable energy sources and subsequently converted back into electricity through fuel cells.
To date, proton exchange membrane water electrolysers (PEMWEs) and alkaline water electrolysers (AWEs) are the most mature and efficient technologies for hydrogen production. However, these systems rely on transition metals such as nickel, cobalt, and iron, which are classified as critical raw materials by the European Union. Consequently, the development of efficient recycling strategies has become a major challenge, particularly in light of European objectives aimed at increasing the proportion of recycled materials in energy technologies.
The RECAT-H2 project aims to develop innovative and environmentally friendly processes for the recovery and reuse of nickel, cobalt, and iron contained in alkaline electrolyser electrodes. The research will focus specifically on the regeneration of catalytic coatings deposited on nickel or stainless-steel meshes, including both porous deposits and electrodeposited alloys.
A key step of the recycling process will consist of dissolving end-of-life materials and subsequently reconstructing them as new coatings exhibiting physical, chemical, and electrocatalytic properties comparable to those of the original materials. This approach will be developed using non-conventional solvents, namely ionic liquids (ILs) and deep eutectic solvents (DESs).
Recent advances in alkaline water electrolysers have relied on innovative nickel-based alloy coatings (Ni-Co, Ni-Fe, Ni-Cu) as well as porous structures produced through the Dynamic Hydrogen Bubble Template (DHBT) technique. The primary challenge of the project will be to identify and control the parameters enabling the direct regeneration of these coatings from the dissolution medium itself. An important scientific question will be to assess whether a DHBT-type approach can be successfully implemented in ionic liquids or deep eutectic solvents. In addition to research into the electrodeposition of coatings, work will be carried out on the design of a pilot-scale leaching/redeposition plant.
Another major scientific challenge will concern the control of the chemical composition of the regenerated coatings, particularly in the case of multicomponent alloys. To address this issue, chemical and electrochemical dissolution studies will be carried out in various families of ionic liquids and deep eutectic solvents. Extraction yields will be quantified using appropriate analytical techniques, including ICP-OES and atomic absorption spectroscopy (AAS), in order to identify the most effective media for the selective leaching of nickel and nickel-based alloys.
The research will also investigate the influence of several experimental parameters, including temperature, atmospheric control, mechanical stirring, and ultrasonic agitation, with the objective of maximizing extraction efficiency while minimizing substrate degradation and contamination phenomena.
The second part of the PhD project will focus on the electrodeposition of nickel and nickel-based alloys from the leaching solutions. Particular attention will be paid to deposition selectivity and alloy composition control. In the specific case of porous coatings prepared by the DHBT method, the competition between metal electrodeposition and hydrogen evolution will be investigated in order to control the final morphology of the deposits.
The regenerated materials will undergo comprehensive characterization to evaluate their composition, structure, crystallographic texture, morphology, and adhesion properties. These investigations will rely on the extensive facilities available at both the Surface Reactivity Laboratory (LRS) and the UTINAM Institute, including SEM, XRD, GDOES, and advanced electrochemical characterization techniques.
This PhD project will be carried out jointly between the Surface Reactivity Laboratory (LRS, Sorbonne University, Paris) and the UTINAM Institute (Marie and Louis Pasteur University, Besançon) within the framework of a close collaboration between the two laboratories.

Your Work Environment

This PhD research will be carried out at the Surface Reactivity Laboratory at Sorbonne University, Paris, in close collaboration with the UTINAM Institute at Marie and Louis Pasteur University in Besançon.

Constraints and risks

-

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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