A comprehensive study on the sulfur doping of TiO 2 , by means of H 2 S treatment at 673 K, has been performed in order to highlight the role of sulfur in affecting the properties of the system, as compared to the native TiO 2 . The focus of this study is to find a relationship among the surface, structure, and morphology properties, by means of a detailed chemical and physical characterization of the samples. In particular, transmission electron microscopy images provide a simple tool to have a direct and immediate evidence of the effects of H 2 S action on the TiO 2 particles structure and surface defects. Furthermore, from spectroscopy analyses, the peculiar surface, optical properties, and methylene blue photodegradation test of S-doped TiO 2 samples, as compared to pure TiO 2 , have been investigated and explained by the effects caused by the exchange of S species with O species and by the surface defects induced by the strong H 2 S treatment.

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Tailor-made nanostructured ZnO cages have been catalytically grown on Au and Pt films covering silicon substrates, by a controlled evaporation process, which means an accurate choice of temperatures, times, gas flows (He in the heating, He/air during the synthesis), and Au/Pt film thickness. The effect of the process parameters affecting the morphology and the structure of the obtained materials has been investigated by XRD analysis, scanning electron microscopy (SEM) and atomic force microscopy (AFM) microscopies, and FTIR spectroscopies. In particular, the role of the synthesis temperature in affecting the size and shape of the obtained ZnO cages has been highlighted. It will be shown that by adopting higher temperatures, the protruding nanowhiskers several microns in length, covering the cages and exhibiting both basal and prismatic faces, change into very thin and narrow structures, with extended prismatic faces, prevailing with respect to the basal ones. At an even higher process temperature, the building up of Au particles aggregates inside and/or anchored to the walls of the hollow cages, without any evidence of elongated ZnO nanostructures will be highlighted. From FTIR spectra information on lattice modes of the investigated ZnO, materials have been obtained.

Polyamide 66 (PA66) is a well-known engineering thermoplastic polymer, primarily employed in polymer composites with fillers and additives of different nature and dimensionality (1D, 2D and 3D) used as alternatives to metals in various technological applications. In this work, carbon black (CB), a conductive nanofiller, was used to reinforce the PA66 polymer in the 9–27 wt. % CB loading range. The reason for choosing CB was intrinsically associated with its nature: a nanostructured carbon filler, whose agglomeration characteristics affect the electrical properties of the polymer composites. Crystallinity, phase composition, thermal behaviour, morphology, microstructure, and electrical conductivity, which are all properties engendered by nanofiller dispersion in the polymer, were investigated using thermal analyses (thermogravimetry and differential scanning calorimetry), microscopies (scanning electron and atomic force microscopies), and electrical conductivity measurements. Interestingly, direct current (DC) electrical measurements and conductive-AFM mapping through the samples enable visualization of the percolation paths and the ability of CB nanoparticles to form aggregates that work as conductive electrical pathways beyond the electrical percolation threshold. This finding provides the opportunities to investigate the degree of filler dispersion occurring during the transformation processes, while the results of the electrical properties also contribute to enabling the use of such conductive composites in sensor and device applications. In this regard, the results presented in this paper provide evidence that conductive carbon-filled polymer composites can work as touch sensors when they are connected with conventional low-power electronics and controlled by inexpensive and commercially available microcontrollers.

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MoS 2 /TiO 2 -based hybrid structures have been synthesized, via a bottom-up approach, by sulfidation, with CS 2 as sulfiding molecule, of molybdenum oxide precursor supported on high surface area hydrogen titanate nanotubes (HTNTs). The evolution of morphology and structure of the support, moving from titanates to TiO 2 phases together with the simultaneous formation of MoS 2 nanosheets have been imaged by means of AFM, HRTEM microscopies, while the vibrational and the optical properties have been investigated by FTIR and UV−visible techniques after each step of the process. More in detail, the different stacking degrees, the size distribution of the MoS 2 nanosheets, decorating the heterogeneous supports, have been carefully obtained by means of HRTEM. In order to explore the nature of the surface sites on the exposed faces, in situ FTIR spectra of adsorbed CO as probe molecule have been carried out. It was shown that the sulfidation steps are affecting not only the structure of MoS 2 nanosheets, including their curvature, surface defects, and stacking order, but are involving the support, too, and then in turn the MoS 2 / support interaction, so helping to control and preserve the size of the particles. Lastly, to elucidate the nature of the hybrid composites, a simple scheme summarizing the reaction pathways has been proposed.

The field of two-dimensional (2D) layered nanomaterials, their hybrid structures, and composite materials has been suddenly increasing since 2004, when graphene—almost certainly the most known 2D material—was successfully obtained from graphite via mechanical exfoliation [...]

The discovery of the carbon nanotubes has opened up a new field in biomedical research. Indeed, the recognition of carbon nanotubes by DNA, DNA assisted separation of carbon nanotubes, DNA immobilization on carbon nanotubes surfaces have been demonstrated. The knowledge of carbon nanotubes-DNA interaction is of fundamental importance for using carbon nanotubes/biomechanical complexes. In this study experimental and theoretical study of the DNA-interface coupling is performed to achieve better understanding of the properties of many carbon nanotubes-based biosystems, as well as novel phenomena caused by the interaction of carbon nanotubes with biomolecules. This paper is focused on the study of interactions between single walled carbon nanotube (SWCNT) surfaces with DNA, poly-A, and individual nucleotides, to clear up the conformation changes in these complexes. New spectroscopic technique based on the effect of enhancement of infrared (IR) absorption by rough metal surface (SEIRA) together with surface enhanced Raman spectroscopy (SERS) and atomic force microscopy (AFM) for registration of structural changes in carbon nanotubes and DNA/carbon nanotubes complexes were applied. SEIRA spectroscopy data was compared with ab initio quantumchemical calculations performed for thymine and adenine adsorbed on carbon nanotubes. A possible model of interaction between nucleic acid bases, double and single nucleic acid strands and the carbon nanotube surfaces is derived from the experiments and calculations.