Cultural heritage, as represented by collections in museums and the built environment, is a unique resource in socio-cultural and economic terms. Climate change will lead to extreme events such as droughts and floods, severe storms and heat waves occurring more frequently across Europe. While the impact of climate change on society and ecosystems has garnered significant attention, the consequences for cultural heritage have largely been overlooked. The major factor controlling the impact of climate change on heritage buildings hosting collections, surrounded by natural environments is water (in excess or in stress) and its transfer. In this context the project aims to understand the role of the water cycle on cultural heritage site conservation with an holistic approach considering water dynamics at three scales : - The liquid water in the natural environment (soil and vegetation in gardens and parks) - The liquid to vapor water transfer within the architectural building envelope (monument) - The vapor to liquid water in interiors and collections (condensation phenomena) This research explores how heritage sites can be resources for climate mitigation, adaptation and sustainable development through optimal management of the water cycle in and around them. Our objective is to identify levers at the heritage site scale to optimise conservation of cultural heritage while improving water management and reducing energy consumption. To achieve the project objective, a transdisciplinary approach will combine historical, experimental, theoretical and numerical studies of water transfers across three scales at real heritage sites with respect to climate data. Building on the resultant improved understanding of water transport, passive solutions as well as innovative materials and techniques will be integrated and optimized. Using these levers, the project will establish how the nature-culture relationship (soil-vegetation-buildings-museum collections) could be the key to making European cultural heritage more resilient.

Aiming at enhancing the work-hardening behavior of strategic light-weight and corrosion resistant Ti-alloys, the TWIP (twinning induced plasticity) Ti-alloys family was developed. Playing with the stability of the ?-phase (body centered cubic), the TWIP mechanism can be triggered. Thanks to this alternative deformation mechanism, complementing dislocation glide, a large work-hardening rate could be obtained in alloys of the ?-metastable family, as simple as single-phase binary Ti-15Mo alloy. However, TWIP Ti-alloys display a rather low yield strength. To further optimize the mechanical properties without sacrificing the concept of working on simple systems, the opportunity of microstructure optimization, and in particular tuning the structure and chemistry of the grain boundary, will be investigated. Indeed, grain boundaries are in continuous interaction with the dynamically formed mechanical twins, from their nucleation to a possible twin transmission to a neighboring grain. Although this parameter seems critical to understand and ultimately control the alloy deformation, studies considering the grain boundaries of TWIP Ti-alloys are scarce, and only focus on the mechanism of twin transmission without considering other parameters, such as a possible segregation at the grain boundary. By comparing the Ti-15Mo, Ti-15Mo-xO and Ti-15Mo-1.5Sn alloys, the influence of the grain boundary character (low- or high-angle, at- or out-of-equilibrium following forging-like processes) and its chemistry (from elemental segregation of oxygen or Sn to phase precipitation) on the mechanical twinning (nucleation and transmission) will be assessed. Based on the results, strategies aiming at emphasizing some mechanical properties, such as the yield strength, through grain boundary engineering will be proposed and implemented in a proof of concept.

In the current technological era, the so-called quantum era, great efforts are directed towards the study and application of quantum materials in the most varied technological fields such as quantum information processing, cryptography as well as extreme-conditions sensors development. In this context, diamond finds a leading role as a host platform for quantum color centers. Particularly, the nitrogen-vacancy (NV) color center of diamond has been widely and successfully studied since the 2000s finding extensive use in many quantum devices, including magnetic imaging, quantum information processing as well as quantum repeaters required for long-distance quantum communications. Nevertheless, the emission of the NV center remains mainly in the phonon broadened line, which limits the efficiency of the spin-photon coupling. This limit can be overcome with centers combining a group-IV atom to a vacancy (G4V center) such as silicon-vacancy (SiV), germanium-vacancy (GeV), tin-vacancy (SnV) and lead-vacancy (PbV) centers, due to the protection induced by the symmetry of the G4V defects. This allows the G4V center luminescence to be concentrated at about 80% of the total luminescence in the zero-phonon line (ZPL). This special property still exists when G4V centers are integrated into nanodiamonds (NDs), allowing them to be efficiently coupled to microcavities for quantum optics and to be employed as single photon source. NDs containing G4V centers are also suitable quantum sensors for high-pressure experiments above megabar and for life science. Our recent studies have shown that microwave assisted chemical vapor deposition (CVD) is a reliable technique allowing the synthesis of high quality NDs in large quantities, without the need for seeds or a substrate, and with considerable degrees of freedom on the incorporation of group-IV impurities (Si and Ge) from a solid-state source into NDs, and on the control of their emissivity. These as-grown SiV- and GeV-NDs have been successfully tested as stress nano-sensors up to pressures of 180 GPa overcoming the reliability limits of traditional and even NV-based sensors. In this scientific context lies the NanoG4V project, which has three ambitious objectives: (1) to synthesise high-quality quantum grade CVD NDs containing G4V color centers with a stable and highly emissive ZPL; (2) to optimize the optical properties of the quantum grade G4V-NDs by high-pressure high-temperature (HPHT) annealing and surface treatments with the aim of reducing color center’s inhomogeneous line distribution close to homogeneous lifetime limit; (3) to control the number of embedded G4V centers per ND and to demonstrate the proof-of-concept sensing: (i) quantum magnetometry under Tesla range magnetic fields and (ii) quantum sensing at stress >100 GPa for extreme sensing experiments. This new generation of quantum-grade G4V CVD NDs will find a wide range of applications, even beyond the extreme-conditions sensing, for example in the field of nanoscale thermometry, live-cell dual-color imaging and drug delivery particle tracking for medical science, that currently rely only on NDs synthesized by a complex HPHT procedure.

The last 15 years have seen the emergence of entire new classes of crystalline nanoporous materials, which exhibit large or anomalous responses to external physical or chemical stimulation. These modifications of framework structure and pore dimensions also involve, in turn, a modification of other physical and chemical properties, making such materials multifunctional (or “smart materials”). One of the outstanding challenges in this field is the systematic synthesis of materials with controlled functionality and porosity. We propose here to remedy this by the development of novel computational chemistry methods that can predict the response of structures under various physical or chemical stimuli. These methods will then be applied on known materials to generate a training dataset for a machine learning procedure, thus allowing to provide rapid screening of large databases of hypothetical materials.

The “PlasmaSolve” project is built upon a multidisciplinary scientific approach, with the long-term objective to unlock pathways for producing organic building blocks and active molecules for medicinal chemistry, with a primary focus on methylation and cyanation reactions. These reactions will take place within microstructured reactors, patented in 2015 and 2018, designed for plasma generation and controlled transfer of radical species from the gas phase to the liquid phase. Initially, this approach was employed to functionalize molecules by exposing them to plasma generated using reactive gases such as O2, NH3, CO. This strategy proved highly effective to functionalize volatile molecules but encountered limitations when dealing with more complex reactions involving heavier molecules, as reactions happen mostly in the gas phase while the liquid phase serves as both reservoir and extraction phase. Therefore, the specific objective of this project is to plasma-activate liquid phases to functionalize dissolved heavy molecules in an appropriate solvent. To achieve this goal, our strategy is threefold: (i) the use of specific organic solvents in which molecules are dissolved, to plasma as we recently observed that the solvent becomes reactive under plasma irradiation; (ii) to accelerate the transfer of radicals produced in the gas phase to the liquid phase by using a new generation of microfluidic plasma reactors so that we can control the gas/liquid interface, and (iii) to integrate these reactors into an innovative sequential flow strategy in an original “micro-lab” platform, that will enable a rapid automated effective exploration of numerous process parameters as well as chemical conditions. If successful, this project based on the use of a reactor which combines plasma and reactive solvents, holds promising prospects for simplifying the synthesis of desired molecules and this may pave the way for new, cleaner, and catalyst-free selective reaction routes.