HEA (high entropy alloys), along with their multiphase recent developments, CCA (complex concentrated alloys), are new classes of metallic materials in which exceptional and improved properties are expected due to the several-element-rich composition of metallic matrix. These alloys are promised for future applications in different demanding areas like in the nuclear industry. The purpose of HERIA project is to evaluate the interest of applications of HEAs/CCAs in this field. The project takes advantage on its members’ expertise: (i) original single phase HEAs, recently designed and developed; (ii) successful development of methodology of numerical design of HEA/CCA alloys. This approach will be used to extend the range of possible applications through design and optimization of new multiphase CCAs, “HE-superalloys”. The whole set of alloys will cover a wide range of industrial interests (defined by project’s industrial partners), as possible substitutes for nowadays used 316SS, but also for more resistant precipitation hardened alloys like A286 or alloy 718. The criteria of success will be determined through an in-depth evaluation of selected alloys, from the point of view of their mechanical properties (yield strength YS, ultimate tensile stress UTS, elongation to fracture, formability) in parallel with their irradiation behaviour. Since very low stress relaxation is expected under irradiation, the stress corrosion resistance could be also an issue for high strength applications encountered in fuel design applications: the alloys that will be developed have to be also optimized for this property. The principal hypothesis is based on bibliographic data suggesting an improved radiation resistance of complex HEA matrices. The project goals are considered in two different fields. The technical objectives deal with the development of new HEAs/CCAs. The scientific objectives focus on: (i) in depth analysis and understanding of irradiation mechanisms and behaviour of HEA matrices, at atomic and microscopic level, including the confirmation of an improved irradiation resistance; (ii) application and improvement of existing alloy design methods to the case of CCAs. HERIA consortium is composed of five academic research labs (or “grand organisme” like DNM-CEA) and one industrial R&D entity, EDF R&D. The two other industrial partners are respectively in charge of (i) HEA elaboration and pre-industrialisation (Aperam); (ii) definition of alloys specification (Framatome); (iii) stress corrosion tests of HEAs/CCAs (Framatome). In this project, structured into five interconnecting work-packages, the consortium applies both experimental and computational approaches. It covers the whole necessary chain of development and evaluation of novel alloys: (i) elaboration, both in industrial-lab (Aperam) and by a unique high-purity cold crucible method laboratory melting (Armines, MINES St-Etienne); (ii) computational design of original and optimised grades (IMN) on the bases of thermodynamic and physical modelling associated to in-house developed genetic algorithms; (iii) access and expertise to use the unique JANNuS platforms associated to long-lasting experience of TEM quantitative analyses (DNM-CEA and CSNSM) to study irradiation defects; (iv) high-level expertise in TAP atomic scale chemical analyses, necessary to understand the phenomena of segregation and pre-precipitation (GPM); (v) long-lasting expertise in atomic scale computational modelling of alloys (DNM-CEA and EDF R&D MMC) especially those considered as “reference materials” in the project. The project will be performed with strong implication of Framatome, the unique European designer and producer of nuclear fuel assemblies.

The present fundamental research and experimental development project is dedicated to the conception, realization and optimization of a hybrid lab-on-a-chip, coupling actuators and biosensors for the active control and broad range characterization of biofluids. The purpose of a lab-on-a-chip is to miniaturize and integrate macro-scale laboratory functions on a chip format. This scale reduction can lead to lower reagent volume consumption, massive parallelization of experiments and better process control. From an industrial perspective, this will entail substantial cost reduction, productivity increase, and reduction of the environmental impact. These advantages are very appealing for biomedical applications. From a scientific point of view, the design of a lab-on-a-chip dedicated to biofluids raises several fundamental and technological issues: - Some biosensors (like Surface Plasmon Resonance (SPR) biosensors) are extremely sensitive to temperature variations. It is therefore necessary to manipulate biofluids within a very narrow temperature range. - A second issue is the precise, real time and adaptive control of biofluid samples. Rayleigh surface acoustic waves (R-SAW) are a versatile tool for displacement, atomization, and mixing of fluids either on the surface of a solid substrate or trapped in confined geometries. However, actuation via acoustic waves can lead to a substantial increase in temperature in the fluid, notably at high viscosity. Finally, the miniaturization and coupling of several biosensors like SPR, microcalorimeter and Love type SAW (L-SAW) biosensors on a chip coupled with R-SAW actuators requires further research. In this project, we will therefore: 1) Investigate thoroughly the physics involved in R-SAW actuators (especially the nonlinear acoustofluidic coupling) to propose efficient original ways of controlling precisely the displacement, mixing and atomization of biofluids with a limited temperature increase. 2) Develop a programmable electronic unit for real time monitoring, adaptive control and characterization of biofluids through the synthesis of suitable complex wavefields. 3) Design and optimize a unique platform allowing droplet manipulation and parallel measurement of a large number of biofluids properties (temperature, pressure, viscosity, binding kinetics, structural characteristics of biomolecules) through the integration and coupling of SPR, L-SAW and microcalorimetry sensors. This highly transverse scientific project, with high potential industrial application, will benefit from the synergy between experts in acoustics, microfluidics, electronics, micro- and nano-fabrication and biophysics. This unique consortium will allow the treatment of both fundamental and technological aspects of this subject. The team will also capitalize on the skills and state of the art technological facilities (clean room, characterization center) of the LN2 (UMI-CNRS 3463), and the Institutes involved in the project.

The MEMPACAP project (48 months) proposes to fabricate compact and encapsulated fast-charge storage micro-sources with high storage capacity, operating in a wide temperature range (-50 to 150°C) and delivering a cell voltage that can be modulated from 10 to 50 volts. To reach this goal, this micro-source will combine a metal-type electrode with a large developed surface area, covered with a dielectric film, with a (pseudo)capacitive electrode to form a hybrid micro-capacitor. The ionic conduction will be achieved by a solid electrolyte (ionogel technology) in its most advanced version. The capacitance of a flat metal/dielectric electrode being low, it will be exacerbated by the use of a 3D hierarchical scaffold with a high specific surface on which the electrode materials (metal and insulator) will be deposited. The second (pseudo)capacitive electrode will be deposited on the back side of a hermetic cap. The application fields are numerous: powering sensors in the automobile industry, implanted defibrillators for the medical sector, energy sources for radar and power lasers, for aerospace and military applications. This collaborative project brings together 4 laboratories (IEMN, UCCS, IMN, CIRIMAT) with complementary skills.

LiNbO3 (LN) and LiTaO3 (LT) are the two of the most important crystals, being the equivalent in the field of optics, nonlinear optics and optoelectronics to silicon in electronics. Thus, the studies about epitaxial ferroelectric LN and LT thin films are of great interest because of their potential application as elements in static random access memories, high dielectric constant capacitors, acoustic delay lines, microwave tunable devices, and optical waveguides. Although LN and LT films have been fabricated by different techniques, many electrical and electro-optical properties reported are not comparable for those of LiNbO3 and LiTaO3 single-crystals. Thus, the degradation of physical properties in thin films can be explained by the difficulty to control and to measure the Li concentration within the film. Moreover, the grain boundaries in polycrystalline films and twin structure in epitaxial ones lead to light scattering and large optical losses in waveguide devices fabricated from these films. Thus, high epitaxial quality, single-domain (twin free) and stoichiometric LN and LT thin films are needed. The aims of this project are challenging: -Deposition of stoichiometric LN and LT films (with 50 mol% of Li); - Elimination of twins and ferroelectric domains in films with thicknesses = 1 µm; -tuning of the thermal expansion of thin films in order to reduce thermal frequency coefficient (TCF) – an important parameter in SAW devices. One of the most promising deposition methods for multicomponent films is pulsed injection MOCVD, providing digital deposition control. The preliminary results obtained on LT and LN film deposition by PI MOCVD are encouraging. The films of high epitaxial quality, consisting of pure LT and LN phase, were deposited. However, all films were twinned. The first measurements of thermal expansion in LN and LT showed that it can changed by SEVERAL TIMES thus, opening a possibility to tune the TCF in thin films. In order to optimize the Li content in the film, the method, able to measure Li concentration with precision of 0.1-0.2 %, is required. The indirect methods, used for the single crystals cannot be applied directly due to the presence of strain, size effects or other defects in the films, which influences also the structural, optical and other physical properties. Therefore, in this project the indirect methods for thin films, based on Curie temperature and Raman mode dampings , will be developed. Then, the Li concentration in films will be optimized varying the deposition parameters or by vapor transport equilibration. The twins and domains will be eliminated by studying the twin formation mechanisms, optimizing deposition and post-deposition conditions or by applying static electric field. The electrical and electro-optical properties of stoichiometric single-domain and twin-free films will be studied. The thermal expansion will be tuned by applying strain engineering and TCF of these films will be studied.

The fluorine element is used in domains as diverse as medicine, energy, microelectronics and everyday plastic objects. Rare in the natural state, a tremendous number of elegant syntheses of fluorinated organic compounds has been developed by using catalysts to improve both activity and selectivity. Catalyzed fluorination by HF in the gas phase is largely operated at industrial scale, essentially for non-functionalized aliphatic fluorinated compounds prepared from chlorinated precursors by Cl/F exchange. In contrast, this strategy is neither applicable to functionalized aliphatic fluorinated compounds due to the sensitivity of most organic functions towards HF, nor for fluoroaromatics which are essentially produced by 2 liquid phase reactions (Balz-Schiemann and HALEX). However, these reactions, poorly selective, generate large volumes of non-recoverable effluents. Therefore, new selective fluorination methods are needed, ideally more efficient, selective and environmentally sustainable. Such an alternative approach, already successfully used for non-functionalized aliphatic fluorinated molecules, is the one-step fluorination of chlorinated aromatic molecules via a gas phase process based Cl/F exchange under anhydrous HF involving catalysts. Additionally, no solvent is required and HCl is the only by-product which is recoverable. Recently, nanofluorides were used as efficient catalysts for the fluorination of 2-chloropyridine. While the selectivity of this reaction is optimal, the activity, related to the weak strength of Lewis acidity of active sites, could be enhanced by increasing the catalyst surface area. Indeed, under harsh conditions (HF gas at 350°C), the nanofluoride catalysts undergo a sintering process leading to a drastic loss of the initially promising surface areas. This stumbling block forces us to explore innovative directions in order to develop such materials, fulfilling the 3 key requirements of a catalyst: activity related to its specific area, selectivity and stability under extreme operating conditions. The innovation of the OPIFCat project is to prepare inorganic fluorinated metallic materials as efficient, selective and stable catalysts under the harsh fluorination conditions of chlorinated reagents under HF gas. In this context, we will explore new architectures and innovative production methods focused on ordered porous inorganic fluorides (OPIFs) supposed to resist such conditions and whose design methodology will be soon patented by the team of IMMM. The chemical composition of the OPIF catalysts will be guided by computer modelling of reaction site chemistry. We will target new Cl/F exchange reactions involving nucleophilic aliphatic and aromatic substitution with five molecules which are involved in domains of energy, agrochemistry and medicine. This project aims to understand the catalyst structure-activity relationship and to establish a “catalyst library” with various strength of Lewis acidity which will help chemists to rapidly select the most appropriate catalyst for the Cl/F exchange as a function of the reactant characteristics (aliphatic/aromatic, activated or not, bearing one or several heteroatoms,…). This OPIFCat project relies on a transdisciplinary consortium with complementary skills, and involves a large industrial group proactive in the sustainable energy transition. It is composed of highly qualified scientists with expertise in the elaboration of fluorinated and polymer materials (IMMM) as well as heterogeneous catalysis (IC2MP), and is completed by an expert of modelling interaction of nanomaterials with reactive species (IMN). Solvay will ensure the scale-up of the OPIF materials and their catalytic properties will be validated in a continuous tubular reactor.