Friday, 27 May 2016, 11:30
Sala Grande Palazzina B via alla Cascata 56/C
Nanostructured Thin Films from Nanocrystalline Inks for Optoelectronic Applications
Università di Padova, Dipartimento di Ingegneria Industriale
Solution-processing is a rapidly growing area in the field of materials science owing to the potential to reduce production costs of high-quality thin films and bulk materials at relatively low temperatures. Of the different wet chemistry techniques, the preparation of nanoparticles by colloidal chemistry and their use as nanocrystal inks permit control of the particle size, size distribution, and shape; crystallinity; and surface states. This approach has been used to obtain surface plasmon resonance based optical gas sensors , transparent conductive oxide coatings  and high and tuneable refractive index nanocomposites based on silk fibroin for biopolymer- based optics .
Noble metal nanoparticles (like Au or Ag) dispersed in a porous semiconductive matrix (like TiO2 or NiO) represent an effective design for a gas sensor’s active material owing to their catalytic and localized surface plasmon resonance properties .
Aluminum-doped zinc oxide (AZO) or gallium-doped zinc oxide (GZO) represent inexpensive alternatives to indium tin oxide (ITO). AZO and GZO nanocrystals that show transparency in the visible range and absorption in the near-infrared range have been synthesized by colloidal chemistry obtaining coating with comparable properties of those prepared by physical techniques .
Silk Fibroin, the protein extracted from the silk fiber, has been used successfully during the last few years as a platform for optics and high tech application with performances comparable to that of the other polymer used in optics. To increase the performances of silk as a material for optics the refractive index is the most important parameter. Here we report on the synthesis of easy tailored refractive index nanocomposite made of silk and titanate nanosheet, a 2D precursor of TiO2, with high refractive index and small size that prevents scattering .
 E. Della Gaspera, et al. Sol-gel thin films for plasmonic gas sensors (2015) Sensors , 15, 16910.
 E. Della Gaspera, et. al. Low-temperature processed Ga-doped ZnO coatings from colloidal inks (2013) J. Am. Chem. Soc. 135, 3439.
 G. Perotto, et. al. Fabrication of Tunable, High-Refractive-Index Titanate-Silk Nanocomposites on the Micro-and Nanoscale (2015) Adv. Mat. 27, 6732.