Study of precipitation in microfluidic-scale droplets of MoZr and actinide oxalate compounds.
Understanding the precipitation reactions that occur during the various stages of the spent nuclear fuel reprocessing process is a major scientific challenge for ensuring optimal control of this process.
In this context, the postdoctoral research project aims to study, at the microfluidic scale, the nucleation of species under different chemical conditions for two key systems:
-On the one hand, the formation of MoZr compounds, for which the aim of the study is to define the precipitation conditions and nucleation mechanism in order to limit their formation in the industrial system,
-On the other hand, the precipitation of plutonium oxalate, for which the objective is to evaluate the impact of hydrodynamics on the particles formed.
Since the microfluidic approach allows for better control of the conditions under which solutions are implemented, it will be essential to develop microfluidic tools suited to studying the precipitation of these species and then to plan their adaptation to a nuclear environment while coupling them with various characterization equipment for conducting parametric tests (SWAXS, DLS, etc.). This work on adaptation to a nuclear environment and system integration will be carried out with the assistance of specialists in this field.
Analysing the potential of Small Modular Reactor in local low-carbon energy systems
Small Modular reactors (SMRs) have the potential to address various energy and environmental challenges beyond electricity generation. Considered at a local or regional scale, SMRs can be fully integrated in innovative hybrid energy systems, including variable renewables and nuclear energy in the form of electricity, heat, hydrogen, energy storage systems, heat networks, and power grids. These integrated energy systems are designed to meet the energy demand of one or more end users. They are currently under development to be ready for commercial deployment for the energy transition. The Euratom TANDEM project (“Small Modular ReacTor for a European sAfe aNd Decarbonized Energy Mix”), coordinated by CEA, developed tools and methodologies between 2022 and 2025 to study the integration of SMRs within hybrid energy systems, and implemented them in illustrative use-cases.
The CEA IRESNE R&D institute invites applications for a post-doctoral position whose aim is to continue the work initiated as part of the TANDEM project by analysing more complex use-cases. The post-doctoral fellow will participate in an international collaboration to define a use case based on the projected energy needs of a large port in Eastern Europe and to propose low-carbon energy systems incorporating SMRs. To this end, these energy systems will be designed through techno-economics and environmental optimization using the Cairn tool developed by CEA. The performances of these energy systems will then be assessed using simulators developed with the Modelica-based TANDEM library.
For the CEA's own purposes, the post-doctoral fellow may also work on the definition and analysis of other relevant use-cases, such as energy supply for an island in the French overseas territories.
This post-doctoral work will be carried out in close interaction between the designers of low carbon energy systems at CEA/IRESNE in Cadarache and the Cairn developers at CEA/LITEN in Grenoble.
Cell manufacturing and electrochemical testing of solid-state batteries
Holding a PhD in electrochemistry, materials science, chemistry, or process engineering, the postdoctoral researcher will work closely with project partners on the development of manufacturing processes and prototyping of solid-state battery cells of 4?? generation (Li/NMC high-nickel) and 5?? generation (Li/Sulfur).
The work will focus on electrode shaping and assembly of solid-state cells, using processes such as coating, extrusion, and alternative approaches including 3D printing. These processes will be optimized to produce prototype cells (button cells and pouch format) with capacities up to 1 Ah, incorporating optimized interfaces. The cells will then be electrochemically tested to evaluate performance in terms of specific capacity, coulombic efficiency, and cycling stability.
Most experimental work will be conducted in controlled environments (gloveboxes), with regular characterization of both electrodes and assembled cells. Main responsibilities will include:
- Contributing to the definition of test plans based on internal data and literature,
- Developing and optimizing manufacturing processes for electrodes and solid-state cells,
- Producing and testing Gen4b and Gen5 prototype cells,
- Evaluating electrochemical performance and analyzing results,
- Presenting results clearly and concisely,
- Proposing improvements, ensuring smooth laboratory operations, and adhering to safety and quality standards,
- Disseminating research through publications, scientific presentations,
Global Power System Modeling under Planetary and Social Boundaries
The EQUALS project (EQUitable Allocation of Low-carbon Electricity Sources in a Changing and Resource-limited World) addresses the challenge of transitioning from fossil fuels to low-carbon energy under the constraint of planetary and social boundaries. While the rapid electrification of end-uses is a major lever against climate change, the transition faces limited natural resources, carbon budgets, and territorial specificities. EQUALS assesses the feasibility of meeting global energy needs within these limits, treating energy as a common.
Based at CEA Liten in Grenoble, this 18-month postdoctoral position establishes the project’s methodological foundations. The mission focuses on the generation of country-level hourly electricity demand time-series. This work involves reconstructing demand profiles that integrate thermal sensitivity (heating and cooling), socioeconomic development trajectories, and the electrification of end-uses. In parallel, vRES (variable Renewable Energy Sources) generation profiles will be developed to quantify resource availability worldwide.
These data will feed a global optimization model to identify transition pathways that minimize reliance on fossil fuels, while respecting social floors and planetary ceilings. The candidate will join the interdisciplinary EQUALS team, collaborating with a network of experts in modeling, energy geography, industrial ecology, and climate science. This position offers a stimulating research environment within the Grenoble scientific ecosystem, bridging technical engineering with sustainability science.
Development of isotopic and elemental analysis methods on irradiated fuels for the reduction of sample quantities.
The objective of this postdoctoral research is to develop analytical methods for the overall reduction of sample quantities required for high-precision multi-element isotopic analysis (actinides and PF) of spent nuclear fuel, particularly through the use of novel "low-quantity" introduction methods on multi-collector ICPMS. These developments will notably reduce the amount of radioactive waste (consumables and effluents), the dose rate, and the exposure time of analysts/radioactive samples associated with this type of measurements.
To carry out this project, the candidate will conduct analytical developments in a controlled environment to minimize the quantities of elements required for analysis while maintaining or improving uncertainty levels compared to currently available methods.
Development of a chloride recovery process by precipitation – Application to molten salt reactors
Molten Salt Reactors (MSRs) represent an innovative option for safer and more sustainable nuclear energy.
They use liquid chloride salts containing actinides, enabling the closure of the nuclear fuel cycle.
During operation, these salts become enriched with fission products and impurities, making chemical treatment necessary.
Enrichment in chlorine-37 aims to limit the formation of chlorine-36, a long-lived radioactive isotope.
Controlling and recycling chloride ions is therefore a major challenge.
The CEA is developing a hydrometallurgical precipitation process to recover enriched chlorine in solid form.
This process is compatible with the La Hague reprocessing plant, in partnership with Orano.
The research focuses on the influence of actinides and fission products on the precipitation reaction and their retention in the solid.
The solubility and purity of the precipitate are studied using various physicochemical techniques.
Purification protocols are optimized when contamination is detected.
Once purified, the solid is recycled to produce reusable chlorine, notably through electrolysis or redox reactions.
This work contributes to the development of innovative reactors and benefits from strong scientific and industrial support.
Robust path-following solvers for the finite element simulation of cracking in complex heterogeneous media: application to reinforced concrete structures
Path-following (or continuation) procedures are used to describe the unstable responses of structures exhibiting snap-back or snap-through phenomena. These methods consist in adapting the external load during the deformation process in order to satisfy a control constraint, by introducing an additional unknown, the load multiplier. Several variants exist depending on the controlled quantity: degrees of freedom, strain measures, or variables related to energy dissipation.
In addition to enabling the tracing of unstable responses, a major advantage of these approaches lies in improving the convergence of incremental Newton-type solvers by reducing the number of iterations required. This gain often compensates for the additional computational cost associated with the continuation algorithm. Some formulations have proven both efficient and simple to implement.
However, no objective criterion yet allows one to determine which formulation is best suited for the simulation of reinforced concrete structures, where multiple dissipation mechanisms coexist along with a strong spatial variability of the material properties.
The proposed postdoctoral work aims to develop robust path-following algorithms for such structures, building upon previous research carried out at CEA. It will include a critical analysis of existing formulations, an evaluation of their performance (monolithic or partitioned solvers), followed by their implementation. Finally, representative test cases of industrial structures will be simulated to assess the gain in robustness and computational cost compared to standard solvers.
TOMOGLASS: Gamma Emission Tomography Applied to the Radiological Characterization of Glass Residues from the Cold Crucible Vitrification Process
The TOMOGLASS project aims to develop an innovative gamma tomography system capable of operating in high-activity environments to characterize in three dimensions the glass residues resulting from the vitrification process of nuclear waste. The objective is to precisely locate platinum-group inclusions, which are poorly soluble in glass, in order to improve the understanding and control of the process. The system is based on a compact gamma imager integrating high-resolution pixelated CZT detectors, pinhole-type collimation, and mounting on a robotic arm. It will enable multi-isotopic reconstruction using advanced tomographic algorithms. This project is part of the modernization of the La Hague facilities and the integration of digital technologies within the framework of the factory of the future.
The first phase of the project will consist in demonstrating the feasibility of implementing a spectro-imager prototype in a constrained environment, building on existing technological components: detection modules and acquisition electronics based on the HiSPECT technology, and image reconstruction algorithms developed at CEA-Leti. The work will focus on conducting a multi-parameter study through numerical simulations (Monte Carlo calculation code) to design an optimized measurement system, and to generate simulated datasets for various representative measurement configurations. Once the concept has been validated, the work will continue in year N+1 with the assembly of the prototype components and their integration on a robotic arm. Experimental tests may then be carried out to demonstrate the system in a representative environment.
Development of an innovative instrumentation architecture using an array of magneto-resistive sensors to create a fast tomography system for fuel cells
Developing an innovative instrumentation architecture using an array of magneto-resistive sensors to create a rapid tomography system for fuel cells.
The goal is to develop a TRL 4 demonstrator in the laboratory to demonstrate a proof of
concept on a low-temperature fuel cell stack. This will include four measurement boards
with several dozen of synchronized magnetic sensors for simultaneous acquisitions. Experimental results and a description of the instrumentation system will be published. Historical data will be used to validate current density resolution algorithms and compare their performance to solutions based on Physics Informed Neural Network. Estimated current density results will be used for an additional publication.
The instrumentation system will be integrated into a CEA test bench dedicated to optimal control, transient observation, fault detection and exploration of defect propagation phenomena. This approach will offer dynamic and non-invasive observation of current distribution in the fuel cell, thereby improving the understanding of its operation and facilitating the optimization of its performance and lifespan.
Modelling and analysis of prospective scenarios for the deployment of hydrogen infrastructure in France and Germany
The use of hydrogen produced by electrolysis or of molecules derived from electrolytic hydrogen (synthetic methanol, synthetic kerosene, etc.) is one of the solutions envisioned to decarbonise certain sectors such as the steel industry and long-distance sea and air transport.
The development of a Europe-wide hydrogen transport infrastructure is considered to facilitate the development of electrolytic hydrogen production on the continent. This infrastructure could provide access to massive underground hydrogen storages unevenly distributed across Europe, facilitate exchanges between regions with high solar or wind energy potential and major industrial hubs and, in certain areas, limit the cost of reinforcing the electricity transmission network.
The goal of the CrossHy project is to analyse the possible deployment pathways for hydrogen transport infrastructure in France and Germany. Two complementary modelling tools (REMix, ANTARES) are going to be used and to develop a European-scale model and a regional-scale model of a cross-border-region.
Regular physical meetings between the French and German research teams are planned during the project; the post-doc will include a 3-month visit to Stuttgart to work and exchange with the DLR team involved in the project.