Post-doctoral position in Solid State Electrochemistry / Ceramic and metallic materials / High temperature corrosion

If, like us, you're interested in strengthening sustainable development, then come and join us! You will work in close collaboration with another laboratory, expert in high temperature non-aqueous corrosion (S2CM/LECNA located in Saclay) and with platforms for ceramic materials fabrication (INSTN in Saclay) and microstructural characterization.

Hydrogen is nowadays considered as an interesting energy vector that could be used in a climate neutral society when combined with an efficient electrochemical system able to produce electricity in fuel cell mode during the peaks of consumption and hydrogen in electrolysis mode during the low demand periods. In this context, the high-temperature electrochemical SOC devices (650-850 °C) are considered as one of the most promising technologies thanks to various advantages such as a high efficiency, a relative low cost and a good reversibility in fuel cell (SOFC) and electrolysis (SOEC) operating modes. If the SOC technology achieves satisfying performances nowadays, SOCs durability needs to be further improved to reach a degradation rate lower than 1%/kh for a life span of about 50 kh and its industrial deployment. Among the involved degradation phenomena, high temperature oxidation of interconnects made of ferritic stainless steel increases system global resistance because of the formation of a poorly conductive oxide scale in both gaseous atmospheres in contact with oxygen and hydrogen electrodes. Moreover, evaporation of chromium initially present in the steel leads to the progressive poisoning of the adjacent electrodes. Then to better understand and limit these phenomena at metal/ceramic interfaces through the use of coatings (supplied by S2CM/LECNA) remains a key challenge for the development of adapted solutions and the optimization of the system durability in SOFC and SOEC operation. Simultaneously to classical studies carried out at STH2 and S2CM on kinetics of interconnect oxidation, chromium evaporation and area specific resistance in relevant operating conditions, PTC-MP-INTERMEDE project has been initiated to study interactions between interconnect, coating and electrochemical cell of small size depending on the operating mode and for long durations (> 3000 h). The post-doctoral work represents the main part of this project and is exclusively funded by it.

For this post-doctoral work, interconnect and cell materials are those classically used in the full-scale CEA stack. The coating material and manufacturing process will be chosen among the most relevant ones developed and characterized thanks to other ongoing studies. The influence of the protective coatings on oxidation and chromium evaporation, and the impact of the contact layer made of LSM (strontium doped lanthanum manganite) in the CEA stack (same thickness and design) as well will be also evaluated and compared to the bare steel. This evaluation will be mainly performed thanks to electrochemical characterizations of performances and durability of the adjacent cell, and post-test microstructural characterizations as well.

Post-doctoral missions will be as follows:

- Adaptation of an electrochemical test bench dedicated to this specific study of interactions between interconnect, coating and SOFC/SOEC cell for an easy introduction of the interconnect ferritic stainless steel in each distinct atmosphere of the oxygen and hydrogen electrodes, and a good distribution of gases and electrical current at the cell surface,

- The management of the associated tests without and with coatings previously selected in collaboration with S2CM/LECNA,

- The fulfilment and analysis of the relevant electrochemical measurements during testing (polarization curves, electrochemical impedance spectroscopy, durability curves),

- The post-test characterizations of the different oxide layers formed on the interconnect surface and the chromium poisoning of the cell electrodes depending on the testing configurations and conditions. Techniques like SEM/EDX, XRD, ICP-OES, XPS and ToF-SIMS could be used for instance,

- In parallel and in a complementary way, long-term oxidation and chromium evaporation tests performed at STH2 on steel samples, in furnaces under atmospheres representative of the oxygen and hydrogen electrode will be followed by the post-doctoral fellow, with the associated post-test microstructural characterizations as well.

In collaboration with technicians of the team, the post-doctoral fellow will take care of the definition and planning of the testing program, its fulfilment from the test mounting to the analysis of the obtained results. He/She will be proactive counting on CEA expertise about SOEC in terms of electrolyte and electrodes materials, corrosion of metals, shaping, electrochemical characterizations of ceramics and microstructural characterisation.

This work should lead to at least 1 publication and 1 presentation at EFCF conference in 2026.

PhD in electrochemistry and/or high temperature corrosion fields

Knowledge and know-how required:

• Good academic knowledge in electrochemistry and/or high temperature corrosion
• Expertise in electrochemical measurements

Skills and qualities required:

• Ability to lead a research program
• Great liking for experimental work
• Ability to ensure dissemination activities (written and oral communication, publications)
• Ability to work in a team
• Autonomy, enthusiasm, energy, kindliness and scientific rigour/precision

The supply of recommendation letters will be appreciated.

English language: fluent.

adapt an electrochemical  test bench and perform 1 or 2 long-term tests on single cells facing interconnect material;

carry out post-test microstructural characterization of tested samples.