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Pd and Pt nanoparticles on Fluorine-doped tin oxide (FTO) are produced. This outcome is reached by processing nanoscale-thick Pd and Pt films deposited on the FTO surface by nanosecond laser pulse. Such laser processes are demonstrated to initiate a dewetting phenomenon in the deposited metal films and lead to the formation of the nanoparticles. In particular, the effect of the film’s thickness on the mean size of the nanoparticles, when fixed the laser fluence, is studied. Our results indicate that the substrate topography influences the dewetting process of the metal films and, as a consequence, impacts on the nanoparticle characteristics. The results concerning the Pd and Pt nanoparticles’ sizes versus starting films thickness and substrate topography are discussed. In particular, the presented discussion is based on the elucidation of the effect of the substrate topography effect on the dewetting process through the excess of chemical potential. Finally, Raman analysis on the fabricated samples are presented. They show, in particular for the case of the Pd nanoparticles on FTO, a pronounced Raman signal enhancement imputable to plasmonic effects.

Non-enzymatic electrochemical glucose sensing was obtained by gold nanostructures on graphene paper, produced by laser or thermal dewetting of 1.6 and 8 nm-thick Au layers, respectively. Nanosecond laser annealing produces spherical nanoparticles (AuNPs) through the molten-phase dewetting of the gold layer and simultaneous exfoliation of the graphene paper. The resulting composite electrodes were characterized by X-ray photoelectron spectroscopy, cyclic voltammetry, scanning electron microscopy, micro Raman spectroscopy and Rutherford back-scattering spectrometry. Laser dewetted electrode presents graphene nanoplatelets covered by spherical AuNPs. The sizes of AuNPs are in the range of 10–150 nm. A chemical shift in the XPS Au4f core-level of 0.25–0.3 eV suggests the occurrence of AuNPs oxidation, which are characterized by high stability under the electrochemical test. Thermal dewetting leads to electrodes characterized by faceted not oxidized gold structures. Glucose was detected in alkali media at potential of 0.15–0.17 V vs. saturated calomel electrode (SCE), in the concentration range of 2.5μM−30 mM, exploiting the peak corresponding to the oxidation of two electrons. Sensitivity of 1240 µA mM−1 cm−2, detection limit of 2.5 μM and quantifications limit of 20 μM were obtained with 8 nm gold equivalent thickness. The analytical performances are very promising and comparable to the actual state of art concerning gold based electrodes.