Laboratory for Molecular Surfaces and Nanotechnology

Dr. Giovanni Li Destri

The research activity mainly exploits state of the art reciprocal and real space techniques, especially graxing incidence X-ray diffraction (GID), grazing incidence small angle X-ray scattering (GISAXS), X-ray reflectivity (XRR) and atomic force microscopy (AFM), to study the soft matter self-assembly processes.

Telefono: 0039-0957385083

Self-assembly at soft interfaces

Giovanni Li Destri’s main scientific interest is the understanding and control of interfacial and intermolecular interactions which occur at soft interfaces, e.g. at the interface between a soft material and a solid substrate or a liquid subphase. These interactions play a fundamental role in the self-assembly processes of soft matter and are particularly relevant in determining the structure of monolayers and ultrathin films. Thus, the research activity focuses on the structural and morphological characterization of soft matter thin films and monolayers and on their interpretation in terms of the different involved interfacial interactions.
In particular, three main research topics are currently ongoing: _ Semi-crystalline polymers, copolymers and composites ultrathin films: The effect of interfacial interactions on polymer crystal orientation and phase separation is investigated. These interactions are mediated by controlling the chemical composition and wettability of the substrate but also by varying its geometrical properties. In particular, close hexagonally packed nanoparticle monolayers with different radius of curvature are employed to study how nano-curvature influence the polymer self-assembly.
_ Glassy block copolymer monolayers: Amphiphilic block copolymers spread at the water/air interface self-assemble into well-defined nanostructures. By modulating the wetting properties of the macromolecules and the interface free energy of the subphase we aim to develop a universal energy landscape which could allow to quantitatively predict the obtained nanostructure for a given polymer/subphase pair.
_ Nanoparticles and surfactants at liquid interfaces: Surfactants and surfactant-decorated nanoparticles spontaneously adsorb at liquid interfaces forming, typically, monolayers. As the adsorption of nanoparticles is generally irreversible, the structure of the resultant monolayers is governed by the interactions between the adsorbed nanoparticles. By modulating the nanoparticle size and the surfactant shell properties, we aim to rationalize the monolayer structure in terms of different inter-particle interactions. Moreover, the adsorption of nanoparticles at liquid interfaces bearing a bio-surfactant monolayer, acting as model biological membrane, is studied as a function of the nanoparticle properties. This will help understanding the fundamental nanoparticle/biomembrane interactions and their role on nanoparticle cytotoxicity.

Selected pubblications

Giovanni Li Destri, Thomas F. Keller, Marinella Catellani, Francesco Punzo, Klaus D. Jandt, Giovanni Marletta
Interfacial Free Energy Driven Nanophase Separation in Poly(3-hexylthiophene)/[6,6]-phenyl-C61-butyric acid methyl ester Thin Films. Langmuir 2012, 28, 5257-5266

Giovanni Li Destri, Antonio Gasperini, Oleg Konovalov
The Link Between Self-Assembly and Molecular Conformation of Amphiphilic Block Copolymers Monolayers at the Air/Water Interface: the Spreading Paramete Langmuir 2015, 31, 8856-8864

L. Costa, G. Li Destri, N.H. Thomson, O. Konovalov, D. Pontoni
Real space imaging of nanoparticle assembly at liquid-liquid interfaces with nanoscale resolutionNano Letters,2016, 16, 5463-5468