SUPRANANO · From metal nanocrystal to supracrystal:crystallinity at nanometer and micrometer scales

The Applicant has an outstanding record of achievement and an international reputation for independent research in many areas of physical chemistry and more specifically over the last 25 years in nanosciences. This large expertise makes it possible, through this project, to come to a decisive turning point in her career. This high-impact and challenging proposal brings together innovative ideas in nanomaterials within a single inter- and multi-disciplinary project to open up new horizons across materials science. The challenging and innovating issue of this project consists in authenticating and detailing the emergence of new chemical and physical properties directly related to the ordering of atoms in nanocrystals (nanocrystallinity) and the ordering of nanocrystals in supracrystals (supracrystallinity). Au, Ag, and Co nanocrystals with different nanocrystallinities (single domain, multiply-twinned and polycrystalline particles) will be synthesized by new methods. Nanocrystals will be used to produce supracrystals of these metals with different supracrystallinities (fcc, hcp, or bcc). The influence of nanocrystallinity on the diffusivity of different atoms within Ag and Co nanocrystals will be investigated. Physical properties of both nanocrystals and supracrystals such as the vibrational, electronic and mechanical properties and their dependence on crystallinity will be explored. From the data thus obtained it should be possible to point out analogies between the properties of atoms in nanocrystals or in the bulk phase and those of nanocrystals ordered in supracrystals. Moreover, correlations between the studied properties could emerge. This research will result in important scientific knowledge and may ultimately open new technological applications.