In the past decade, multilayer thin films drew the scientific community attention for their unique properties. Indeed, principally made of an association of polyelectrolytes and/or nanoparticles, of various morphologies and chemistries; they allow the design of a range of porous nanomaterials with amazing surface and optical properties, such as structural colors or anti-reflectivity. Less commonly encountered, thin films made of two nanoparticles of opposite charges are gaining interest since they open properties compared to polyelectrolytes/nanoparticles thin films. In this study, multilayer coatings were investigated for the association of two oppositely charged nanorods of well-controlled aspect ratio, i.e. anionic Cellulose Nanocrystals (CNC) and cationic Ge-Imogolites. CNC were obtained from hydrolysis of cellulose from cotton linters, and synthetic imogolite (Ge-Imogolite), an aluminogermanate nanotube, was synthetized from the hydrolysis of Al and Ge precursor salts in aqueous media. Here, elaboration of multilayered thin films from CNC and Ge-Imogolites nanorods, was studied in comparison with reference films incorporating CNC or Imogolites with polyelectrolytes bearing opposite charges of the nanorods. Multilayered thin films were assembled by the dipping procedure and various parameters (adsorption time, ionic strength, etc.) were varied to investigate the optimal conditions for the film growth. Linear growth until 10 bilayers revealed that interactions between CNC and Imogolites are strong enough to stabilize the film. Film porosities were investigated using Quartz-Crystal Microbalance with dissipation (QCM-D) with the H2O/D2O exchange procedure as function of film composition and of the aspect ratio of Ge-imogolites. Finally, optical properties of films were investigated by transmittance measurements.

Elaboration of cellulose nanocrystals CNC/Ge-imogolites multilayered thin films

253rd National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.