Metal-Organic Frameworks (MOFs) form a family of porous inorganic-organic ordered hybrid materials which have generated huge interest in the scientific community. Whilst sorption, magnetic, catalytic and drug delivery properties have been largely documented, the basic mechanical properties of these materials have not received as much interest. However, the fact that several structures are highly flexible may be of interest to exploit as dampers or springs as an alternative to previous work carried out on hydrophobic silica based materials. The advantage of MOFs being that the almost infinite possibility to modulate the structure and chemical/physical properties of these materials means that the mechanical properties can equally be tuned. The aim therefore of this fundamental project is twofold : 1) To study the thermodynamic and mechanical properties of selected flexible MOFs in view of (i) establishing pore volume phase diagrams as a function of pressure and temperature, (ii) determining the transition energies between the various phases and (iii) characterizing the structural behaviour under operating conditions up to high temperature and moderate pressure, to compare with theoretical calculations; 2) To evaluate the possibility of using these materials for mechanical storage of energy as dampers or springs. This challenging interdisciplinary project that involves the synthesis of materials, the characterization of the properties of interest and modelling, will be conducted by a subtle combination of innovative experimental tools and advanced molecular simulation approaches, which is expected to yield breakthrough in this domain. It will also bring microscopic insight into the mechanism in play during the phase transition under thermal and mechanical stimuli.

Soil is both the largest sink and source of organic carbon (C) exchanged with the atmosphere. These exchanges result from biological processes, the primary source being the decomposition of soil organic matter (SOM), which is controlled by physical factors such as climate. As such, soil C emissions are very vulnerable to climate change but can also be reduced with new land management practices if we can predict the outcomes of soil carbon-climate feedbacks. However, predictions from the existing large-scale soil C models strongly diverge, and reveal large uncertainties in the processes and controls at play. One of these uncertainties is the effect of change in precipitation regimes on SOM decomposition mediated by soil microorganisms. Functions describing the decomposition response of soil carbon to soil moisture are static in current large-scale models, yet recent empirical studies show that decay responses under new soil moisture conditions can change due to shifts in microbial communities. Recent evidence suggests that evolution is a key processes driving these shifts in microbial communities. This project proposes to integrate variable decomposition-moisture functions into a large-scale soil C model to reflect precipitation history and carbon substrate influence on microbial responses to changing soil moisture. These functions will be calculated from a mechanistic microbial model that accounts for both ecological and evolutionary processes. The mechanistic model will be an updated version of the trait-based model DEMENT developed by the fellow’s supervisor at the partner institution (UC Irvine). The moisture response functions will be integrated into a commonly used soil carbon model, RothC, that has been incorporated into the global land surface model (ORCHIDEE) of the host institution (LSCE).

In the D-FACTO project, we propose to design and fabricate active optical windows based on nanostructured diamond, combining anti-reflective, superhydrophobic, anti-icing and anti-fouling properties. This research project is motivated by the very promising results obtained within the framework of the ANR ASTRID F-MARS project (2019-2022), coordinated by Thales Research & Technology (TRT). In this project, TRT has already shown its capability to simulate and manufacture “multifunctional” windows with broadband anti-reflective and large incidence, superhydrophobic and anti-rain properties in the range of Visible, Midwave InfraRed. and Longwave InfraRed, by developing nanostructuration processes of glass, silicon and germanium respectively. These optical windows aim to meet the needs of many optical and optronics systems used in civil and military fields: land and sea surveillance systems, airborne sensors for threat detection, autonomous train cameras, etc. However, the superhydrophobic nature of these windows, which is fundamental for some of these applications, does not protect these systems, for example, from the formation of various biofilms (marine, hydrocarbons, etc.), nor from the formation of frost. The aim of the D-FACTO project is to extend the multifunctionality of these optical surfaces, by developing robust “active” diamond windows allowing them to be get anti-fouling and anti-ince properties, by using a low current. electrical, coupled (or not) with adequate surface functionalization. Indeed, diamond has intrinsic qualities of interest: in addition to having very good mechanical properties, it is transparent in the ranges from visible to LWIR and it is an excellent thermal conductor. Once doped, it has remarkable electrochemical properties, among which the capacity for electrochemical self-cleaning of its surface and therefore anti-fouling properties. The work of the consortium, composed of two academic partners, CEA-LIST and ILV, and an industrialist (TRT), will first focus on the development of pre-industrial processes for producing optical windows based on synthetic diamond which will benefit from its optical, mechanical and physicochemical "flexibility" advantages for anti-fouling, anti-ince and anti-reflective applications. They will also focus on the understanding and optimizationof the phenomena involved in the self-cleaning and anti-icing mechanisms of these so-called "active" windows. The manipulation of surfaces by electrochemistry of diamond, or else by more conventional surface treatments, should make it possible to modulate its omniphobic capacities. The consortium will thus have various very original functionalization possibilities for optimal physicochemical adaptation. Considering the state of the art, the challenges of the D-FACTO project are the following: • to develop a large area (2-3 inches) process of diamond nanostructuring for anti-reflective applications in Vis, MWIR and LWIR. • to characterize and optimize the growth of doped diamond by taking into account the application constraints (compliance with optical specifications, nature of the substrates in the case of diamond / silicon, diamond / germanium “hydride” windows, etc.). • to optimize the physicochemical properties of the post-nanostructuring process diamond surface and to develop specific chemical engineering based on various surface treatments: “electroless” chemistry, electrochemical assistance, plasma process, etc. • Set up a robust characterization methodology, able of combining fine wettability analysis and chemical analysis by photoemission or Auger emission of diamond, in order to guide the consortium in optimizing the functionalization of nanostructures.

Cancer and bacterial infections are two of the main healthcare challenges humanity has to face nowadays. The side effects and limited efficiency of traditional cancer treatments as well as the development of multi resistant bacteria make it urgent to develop new strategies. Beyond the fact that both are two of the main public health concerns, they are intertwined. The DANthe project objective is to elaborate polyoxometalate (POM) decorated gold nanostars (AuNSs) that combine chemotherapy using a new active agent (POM), photothermal (PTT) and photodynamic therapies (PDT) in the NIR window to obtain unprecedented active tri-therapy drugs acting against both cancer and bacterial infections. We propose herein for the first time to prepare AuNSs using hybrid organic-inorganic POM which will combine the POM specific biological properties, the PTT and the generation of ROS of the AuNSs and singlet oxygen storage/release unit on the organic part of the POM. Preliminary test in cellular environnent under irradiation will be performed to evaluate the nano-object efficiency for the targeted applications.