Fabrication and optical properties of chitosan/Ag nanoparticles thin film composites

摘要: Abstract Chitosan thin films with controlled thickness have been fabricated by spin-coating chitosan acetate and citrate solutions for application as planar optical waveguides (POW). “In situ” reduction of preadsorbed in film Ag + ions sodium borohydride resulted formation chitosan/Ag composites, which silver nanoparticles a size below 10 nm were homogeneously distributed. In contrast to composites formed solution, UV–vis spectra the depicted single narrow adsorption band at 412–413 nm independently content. The absence long-wavelength shoulders spectra, are associated oscillations non-spherical particles or plasmon coupling aggregates, has confirmed SEM data on high uniformity Ag/chitosan composite films. We shown that refractive index wavelength HeNe laser (633 nm) increases from 1.53 1.69 increase volume fraction up 2.55%. Investigations waveguiding properties revealed light propagation is feasible 1.3%, corresponds maximum 1.58.