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The current use of TiO 2 nanoparticles raises questions about their impact on our health. Cells interact with these nanoparticles via the phospholipid membrane and, in particular, the phosphate head. This highlights the significance of understanding the interaction between phosphates and nanoparticles possessing distinct crystalline structures, specifically anatase and rutile. It is crucial to determine whether this adsorption varies based on the exposed facet(s). Consequently, various nanoparticles of anatase and rutile TiO 2 , characterized by well-defined morphologies, were synthesized. In the case of the anatase samples, bipyramids, needles, and cubes were obtained. For the rutile samples, all exhibited a needle-like shape, featuring {110} facets along the long direction of the needles and facets {111} on the upper and lower parts. Phosphate adsorption experiments carried out at pH 2 revealed that the maximum adsorption was relatively consistent across all samples, averaging around 1.5 phosphate·nm -2 in all cases. Experiments using infrared spectroscopy on dried TiO 2 powders showed that phosphates were chemisorbed on the surfaces and that the mode of adsorption depended on the crystalline phase and the nature of the facet: the anatase phase favors bidentate adsorption more than the rutile crystalline phase.

Young's moduli of cellulose nanofibril (CNF)-poly(allylamine hydrochloride) (PAH) multilayered thin films were measured using strain-induced elastic buckling instability for mechanical measurements (SIEBIMM) and the quantitative nanomechanical mapping technique (PF-QNM). To establish the relationship between structure and mechanical properties, three types of films with various architectures were built using the layer-by-layer method by changing the ionic strength of the dipping solution. Both methods demonstrate that the architecture of a film has a strong impact on its mechanical properties even though the film has similar cellulose content, emphasizing the role of the architecture. Films with lower porosity (Φ air = 0.34) and a more intricate network display the highest Young's moduli (9.3 GPa), whereas others with higher and similar porosity (Φ air = 0.46-0.48) present lower Young's moduli (4.0-5.0 GPa). PF-QNM measurements indicate a reverse ranking that is probably indicative of the surface composition of the films.

Highly stable single-walled carbon nanotube (SWNT) dispersions are obtained after ultrasonication in cellulose nanocrystal (CN) aqueous colloidal suspensions. Mild dispersion conditions were applied to preserve the SWNT length in order to facilitate the identification of hybrid objects. This led to a moderate dispersion of 24% of the SWNTs. Under these conditions, atomic force microscopy (AFM) and transmission electron microscopy (TEM) experiments succeeded in demonstrating the formation of hybrid particles in which CNs are aligned along the nanotube axis by a self-assembly process. These SWNT/CN dispersions are used to create multilayered thin films with the layer-by-layer method using polyallylamine hydrochloride as a polyelectrolyte. Homogeneous films from one to eight bilayers are obtained with an average bilayer thickness of 17 nm. The presence of SWNTs in each bilayer is attested to by characteristic Raman signals. It should be noted that these films exhibit a near-infrared luminescence signal due to isolated and well-separated nanotubes. Furthermore, scanning electron microscopy (SEM) suggests that the SWNT network is percolating through the film.