Every year, more than 200 000 orthopaedic prostheses (knee, hip) and a huge (but unknown) number of dental implants are implanted in France. For an optimal efficiency, these implants have to be well integrated in bone. To favour osseointegration, dental implants rely on modification of their surface morphology, while a Calcium-Phosphate coating is often required on the surface of orthopaedic implants. Traditionally, these coatings are fabricated by plasma-spray, leading to well crystallized films in the most stable phases (mainly hydroxyapatite).Even though these plasma-sprayed coatings are commonly used on stems and metal-backs of hip prostheses, their efficiency is subject to controversy because of several drawbacks such as the excessive thickness of the coatings, their possible delamination leading to local inflammations, and the overly stable nature of the constitutive materials that do not favour reactivity. DECaP project aims at developing alternative coating techniques, less costly and leading more efficient coatings (with higher adhesion to substrate, more reactive to allow faster bone ongrowth and faster healing of the patient) potentially applicable to both dental and orthopaedic implants. The consortium will thus use ElectroSpinning (ES) and Electrostatic Spray Deposition (ESD) to fabricate (and characterize) osseoconductive coatings of optimized architectures, compositions and structures (amorphous or crystalline), on biomedical grade titanium substrates. We will aim at biologically reactive coatings such as out-of-equilibrium or amorphous calcium phosphates (highly difficult to stabilize as coatings by any other technique, thus their potential as osseoconductive coatings could never be assessed) or bioactive glasses (whose synthesis has never been attempted using ESD). Moreover, we will look for architectures that promote reactivity and mechanical adhesion to bone tissues: dense coatings with arborescent surface, and porous coatings with a large amount of porosity (easily obtained with ES), or even with a multiscale architecture (network of tubular pores inside a coral-like dense matrix). As a proof of concept, these findings will be applied to a real dental implant. The expected outputs of this project are: - Scientific: obtaining stable over time, out-of-equilibrium, reactive CaP or bioactive glass phases is a scientific challenge. Understanding how these phases are stabilized during the process could open the way to new materials with original properties (reactivity, transport…) - Industrial: after further development, the findings of DECaP project will allow biomaterial companies to implement new processes leading to innovative and efficient coatings for improved osseoconductivity of biomedical implants. - Societal: the improved osseoconductiviy of these implants will allow faster healing of the patients, thus better comfort, shorter treatments thus lower treatment cost and hopefully better long term success. Besides these cheaper coatings will help reduce the price of implants. DECaP consortium combines the competencies of three laboratories: MATEIS will bring its knowledge of calcium phosphates and extensive, in-situ characterization. LEPMI will use its in-depth understanding and practice of Electrostatic Spray Deposition, already applied with great success to the fabrication of Solid Oxide Fuel Cell components. LMI masters Electro Spinning, that was used (combined with sol-gel chemistry) to fabricate original and architectured materials.The synergy between the three laboratories will allow reaching our ambitious goals.

The present PRC deals with the Redox Flow Batteries (RFB) used for the conversion and the storage of renewable electrical energies under chemical form, as well as the reversal procedure. The project, based on the knowledge acquired into the RFB “all-liquid-all-Vanadium/V-RFB” and the Semi-Solid lithium based RFB, introduces an entirely new (no works find bibliography) concept: “all-aqueous, all-Vanadium, Solid(crystalized V salts)-Liquid(dissolved V salts) Redox Flow Battery (VSL-RFB)”. It expects to overcome the limitations of the V-RFB (specifically ‘the low solubility->low stored energy ~40 kWh/m3), by “scientific” and “technological” actions enabling to i) bring new knowledge in the field, ii) to design, manufacture and optimize a VSL-RFB able to deliver 100 W. The scientific and technical actions consist: -to elaborate and characterize concentrated flowing suspensions containing more than 500 g/L of VSL, in order to increase the energy stored up to 350 kWh/m3, as well as to reduce the stored volume (ratio: 10mol/L/~1.6M=~6), -to introduce nano-metric carbon black additive (KB) into the formulation, expecting to create: a) electronic percolation into the bulk, thus enhancing the electrochemical surface area of the collector (×5 Sgeom.) and consequently the answer in current of the reactor, and b) catalytic seeds for the ‘rapid’ V salts dissolution and precipitation, -to intensify the electrochemical reactor by: i) the optimization of the geometry, the shape and the structure of the electrolytic compartments enabling to control the non-Newtonian fluid flow, avoiding dead zones (uniform distribution of the residence time), ii) the use of three dimensions electronic collectors (porous or milli/micro-metric scale grooved plates) enabling the increase of the electrochemical surface area (×5 Sgeom.). The expected current density is 2 kA/m², (instead 0.6kA/m² for V-RFB). The proposal is structured into two parts, each one constituted by two tasks, and each task leaded by a partner from a specific scientific domain. Fundamental characterization of the system is the target of the first part (Tasks 1 and 2). Task 1 leaded by NAVIER/Coussot, focuses on the rheological and electrochemical characterizations of the above described formulations of V+ KB, and expects to propose the corresponding laws to help for the building of the battery. Specifically will be treated: a) the elaboration of the suspensions, b) the study of their electrochemical properties, c) their rheological behavior in defined reactor geometry. The task T2 leaded by the LGC-INPT/Biscans, focuses on the kinetics of the V salts (Vs) phases-change i.e. Dissolution/Crystallization (D/C); it expects to understanding the mechanisms and to define the laws providing the D/C rates. The effect of the KB on the rate of the Vs (D/C) as well as the favored D/C locations in the reactor, will be examined. The second part concerns more the innovative technological actions: Task 3, leaded by the LGC/UTIII-PS/ Tzedakis aims to design, and to optimize one module of the electrochemical reactor and then to build the prototype (100 W); Task 4, leaded by the LEPMI/Bultel, focuses on the modelling of the electrolytic compartments in order to access to the concentration profiles of all the V species, as well as the current density in the reactor. The strategy chosen in order to achieve the objectives of the project consists of two points: -The full treatment of the whole process of the VSL-RFB, which justifies the choice of the multidisciplinary and complementary consortium. -The structuration of the skeleton of the project (mixing of the partners into the tasks) which, in addition to the planned meetings, enables high interactivity and favors ‘easy, significant and permanent’ exchanges. Finally, this project, involves 247.5 person.month, for an overall duration of 42 months and presents a financial demand of 606 k€ on a total budget of 1.8M€.