Theme B : Properties

Properties

The properties of nanostructures result from the association of their different components and their complex interactions.

If we focus on the individual nano-object, its core, which we define here as the inorganic part, is characterized by specific properties which depend on its structural characteristics such as composition, size, shape, crystallinity, the state of oxidation but also its defects and its deformations. Its degree of complexity can vary with, for example, the introduction of a solid/solid interface (core/shell), impurities or dopants. Interactions between components can thus generate particular properties which differ from the original properties of the components.

The properties of nanostructures also depend on the interactions between nano-objects when they are assembled in structures such as simple or more complex 2D and 3D supercrystals (binary, ternary, etc.). Resulting from collective interactions between nano-objects, new properties (mechanical, transport, optical, magnetic, vibrational, chemical) emerge, and can be adjusted through various parameters including the distance between the nano-objects and their type of stacking.

The stability of nanostructures is also an important parameter to take into account. The properties of nanostructures, before and after their integration into application devices and during their use, directly depend on them. The life cycle of nanostructures, from their formation to their valorization, must therefore be considered.

We will be interested in the physicochemical properties of nanostructures, intrinsic to nano-objects, and/or modulated by inter-particle interactions or in interactions with the environment (optical, electronic, vibrational, magnetic/magneto-optical, magnetotransport, chemical reactivity). The general objective is to establish “structure-property” relationships in order to:

(a) control the physical and chemical properties of the nanostructures and

(b) discover new properties.

To optimize the physicochemical properties of inorganic nanostructures and bring new ones to the surface, we propose to take up three major challenges:

(1) We will be interested in the influence of key parameters (composition and structural characteristics of the inorganic core, integration of dopants, impurities, solid/solid interfaces, anion exchange, collective interactions in assemblies, etc. ) on a set of properties (chemical, optical, vibrational, magnetic, electronic, catalytic, etc.). This GDR will be an ideal setting for the emergence of such an understanding which requires transcending the separations commonly present between communities interested in restricted ranges of materials and properties.

(2) Bringing together all of this data will allow us to establish the scientific basis and concepts from which we will identify the numerous combinations of parameters to adjust to optimize the desired properties but also to bring out new ones.

(3) Using this approach, numerous nanostructures will be developed toward optimization of their properties.