Nanoscale Research Letters
2014
A comparative study of two different approaches for the incorporation of silver nanoparticles into layer-by-layer films
PEDRO JOSE RIVERO; JAVIER GOICOECHEA; IGNACIO RAUL MATIAS; FRANCISCO JAVIER ARREGUI

Abstract

In this work, a comparative study about the incorporation of silver nanoparticles (AgNPs) into thin films is presented using two alternative methods, the in situ synthesis process and the layer-by-layer embedding deposition technique. The influence of several parameters such as color of the films, thickness evolution, thermal post-treatment, or distribution of the AgNPs along the coatings has been studied. Thermal post-treatment was used to induce the formation of hydrogel-like AgNPs-loaded thin films. Cross-sectional transmission electron microscopy micrographs, atomic force microscopy images, and UV-vis spectra reveal significant differences in the size and distribution of the AgNPs into the films as well as the maximal absorbance and wavelength position of the localized surface plasmon resonance absorption bands before and after thermal post-treatment. This work contributes for a better understanding of these two approaches for the incorporation of AgNPs into thin films using wet chemistry.

Fabrication of the thin films

All the thin films have been fabricated using a 3-axis Cartesian robot from Nadetech Innovations SL (Sarriguren, Spain). The LbL assembly was performed by sequentially exposing the glass slides to cationic and anionic polyelectrolytes with an immersion time of 2 min. A rinsing step in deionized water was performed between the two polyelectrolyte baths. The combination of a cationic monolayer with an anionic monolayer is called bilayer. 

 

Keywords: Silver nanoparticles; Thin films; In situ synthesis process; Layer-by-layer embedding deposition technique