18-month postdoctoral position in Ni-Al alloy cathode development for hydrogen production

Numerical simulation of gas bubble behavior: from nucleation to detachment in electrolysis 
Framework of this EU-funded research program: 
To date, hydrogen production has primarily relied on grey hydrogen, derived from fossil fuels, releasing approximately 70-100 million tons of CO₂ annually in the EU. To transition toward responsible hydrogen use, it is essential to adopt green hydrogen-produced sustainably via water electrolysis powered by renewable energy. In this process, water undergoes a redox reaction: high-purity hydrogen is generated at the cathode through the Hydrogen Evolution Reaction (HER), while oxygen forms at the anode via the Oxygen Evolution Reaction (OER). However, this method is not yet economically competitive, as it requires significant electrical energy and lacks the efficiency of established grey hydrogen production routes. 
Efficient production technology is critical to making hydrogen a viable energy carrier. Industrial insights from P5 (SF), a participating electrolyzer company, highlight the cathode as the area with the greatest potential for improvement. In Alkaline Water Electrolyzers (AWE), nickel stands out as a promising cathode material due to its catalytic properties and its ability to replace costly or critical materials like platinum or cobalt. Meanwhile, existing anode materials-such as nickel-(iron) oxides-already rely on less critical resources. To achieve competitive cathode performance, maximizing the active reaction surface is key. Open-pored structures with a high specific surface area outperform solid materials, and nickel cathodes can only compete with established solutions through such designs. Thermal spraying offers a viable method for creating such structures. 
For cathode development, the nickel-aluminum alloy Raney Ni, already proven effective in hydrogen production, is an ideal candidate. Combining thermal spraying with subsequent leaching of the porous structure unlocks significant synergy potential. Beyond increasing the outer surface area, this approach also enhances the inner surface area, thereby boosting the cathode material’s reactivity. In this context, this project aims to holistically develop a process chain for next-generation cathodic materials in alkaline water electrolysis. This involves advancing Raney Ni derivatives in terms of processing technology and functional properties. Evaluating all relevant thermal spraying process variants within a system unit and followed by leaching enables a thorough assessment of process-structure parameters. Functional testing completes this development approach, providing a solid foundation for identifying optimal material-process-system solutions. 
This project involves multidisciplinary challenges. Scientifically, it requires a deep understanding of powder metallurgy, thermal spraying technology, alloy composition, and computational fluid dynamics (CFD) as applied to water electrolysis. Technologically, the focus lies on scaling up laboratory processes for industrial production and enhancing cathode properties, particularly efficiency, robustness, and service life. These challenges are tackled through collaboration with industrial partners within the project consortium and other stakeholders. The ICB-Lermps PMDM Laboratory at UTBM provides its expertise in metal powder manufacturing, simulation thereof and electrochemical characterization. 

This postdoctoral R&D project will focus on the modeling and analysis of hydrogen (H₂) gas bubble nucleation, growth, detachment, and removal in porous Raney Ni-based cathodes for alkaline water electrolysis. The research will combine multiphase and multiphysics numerical simulations with physical experiments to investigate the dynamic behavior of bubbles and their relationship with pore structure, including pore size, pore shape, porosity, and connectivity. 
Computational Fluid Dynamics (CFD) simulations will be employed to assess the in-operando gas-liquid two-phase flow behavior of developed catalyst layers within alkaline electrolysis cells. This approach will enable: 
•    Performance benchmarking against reference catalysts and electrode structures;
•    Investigation of the influence of porous coating architecture on bubble transport and mass transfer;
•    The creation of a virtual platform for testing and optimizing innovative Raney electrode design concepts.
The simulation results will deepen the theoretical understanding of electrode processes, particularly for water electrolysis using Raney alloy-based coatings produced via thermal spraying and subsequent leaching. The data will also support comparisons between experimental observations and numerical models, providing guidance for the design of scalable, high-performance cathodic porous electrodes. 
The selected candidate will be responsible for leading the gas-liquid simulation and bubble dynamics part of the project through the end of the postdoctoral period. Key tasks will include: 
•    Conducting a comprehensive literature review on models for gas bubble nucleation, growth, detachment, coalescence, and removal from porous electrodes, and selecting suitable models for implementation;
•    Performing CFD simulations of hydrogen bubble dynamics in alkaline electrolysis under laboratory conditions, incorporating the selected model from the literature review;
•    Investigating the effects of pore size, pore shape, porosity, pore connectivity, and surface properties on bubble behavior and cathodic performance;
•    Evaluating and modeling potential coating design strategies to reduce bubble accumulation and minimize its impact on mass transport and electrochemical efficiency;
•    Developing CFD models for industrially relevant cell configurations, including fluid flow and gas-liquid transport simulations, to guide the design of scalable electrolyzers;
•    Testing, validating, and analyzing data from technological demonstrators.
•    Documenting findings through technical protocols, tutorials, work reports, and publications.
•    Facilitating project progress, including active participation in meetings with partners.

PhD in Mechanical Engineering, with strong background in Computational Fluid Dynamics (CFD) and multiphysics/multiphase simulations, knowledge of bubble nucleation and growth dynamics in porous media, proficiency in numerical modeling tools (COMSOL, ANSYS Fluent).