Bimetallic nanoclusters (bNCs) are at the forefront of research in chemical physics for their peculiar structural, electronic and catalytic properties, which are different with respect to those of bulk materials and alloys and of mono-metallic nanoparticles. The capability to control… Leggi tutto their size and composition allows to tune their properties and to optimize the use of precious metals, which are often of high cost and difficult supply. In addition, their catalytic properties can be influenced by the presence of the solid support under two aspects: i) the anchoring of the nanoparticles to the substrate enhances the stability of the catalyst through the life cycle and prevents adverse aggregation phenomena; ii) the chemical interaction with the support can modify the catalyst and represents a promising tunable factor to enhance the particle’s activity. In particular, the interaction with the support may affect shape, charge state and electronic structure of the metal cluster. Current front-line research focuses on ultrasmall particles, that represent the ultimate limit for the optimal use of precious materials due to their extremely large surface to volume ratio. In this limit, moreover, the simplicity of the NC shape leads to a higher selectivity, while a larger fraction of atoms are located at the cluster/substrate interface and are chemically modified by their bonding with the substrate. In the Bi-NANO project we intend to study the physical and chemical properties of bNCs used for the conversion of biomasses. If derived from wood and agricultural residues, biomasses are often rich in lignin, cellulose and hemicellulose, which are an excellent base for the production of fuel and chemicals, but have a large oxygen content. The latter can be reduced by dehydration and hydrodeoxygenation, for which reactions bNCs are promising catalysts. We propose to investigate the processes underlying the chemical reactions of high economic and environmental relevance mentioned above on well-defined model systems. This research will provide elements for a knowledge-based optimization of the current protocols and hints for the design of new active systems. For this reason, we will focus our attention on Pt-Zn, Ru-Cu and Cu-Pt bNCs of ultra-small size, i.e. up to a few tens of atoms, supported on MgO or graphene. We will study the interaction of these systems with very simple reactants (e.g. ethylene glycol and benzaldehyde) that contain, however, some of the functional groups (OH, C=O) involved in the deoxidation processes occurring in biomass conversion. Our analysis will take advantage of the complementary competences of the research team, which combines the most advanced experimental methods of surface and material science (scanning probe microscopy, photoemission and vibrational electron-based spectroscopies, thermal desorption spectroscopy) with up-to-date density functional theory calculations.