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Silicon nanowires (SiNWs) decorated by pulsed laser ablation with gold or copper nanoparticles (labeled as AuNPs@SiNWs and CuNPs@SiNWs) were investigated for their catalytic properties. Results demonstrated high catalytic performances in the Caryl–N couplings and subsequent carbonylations for gold and copper catalysts, respectively, that have no precedents in the literature. The excellent activity, attested by the very high turn over number (TON) values, was due both to the uniform coverage along the NW length and to the absence of the chemical shell surrounding the metal nanoparticles (MeNPs). A high recyclability was also observed and can be ascribed to the strong covalent interaction at the Me–Si interface by virtue of metal “silicides” formation.

An aromatic epoxy monomer, formed by glycidylation of gallic acid, was crosslinked by adopting different curing agents to obtain bio-based, crosslinked resins with suitable engineering properties. Specifically, triand tetra-glycidyl ether of gallic acid (GEGA) were obtained using a twostep synthesis. These bio-based monomers were cured in the following three epoxy formulations: a stiff cycloaliphatic primary amine, isophorone diamine, and a flexible polypropylene oxide amine (Jeffamine D-230). Next, the homopolymerization of GEGA was studied using an ionic initiator, N,N-dimethylbenzylamine, and a complex curing mechanism highlighted by calorimetric and mass spectra analysis. Calorimetric and rheological measurements were used to compare the curing behavior of the studied GEGA-based formulations. Mechanical properties of the gallic acid-based epoxy resins were comparable with those of standard epoxy resin formulations, based on di-glycidyl ether of bisphenol A. Thermogravimetric analysis of cured samples showed a relevant char content at high temperatures.

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