Surface Gold and Silver-Polymer Nanocomposite Self-Standing Films

Abstract

Surface gold (silver)-polymer nanocomposites are an emerging category of composite materials not studied in a systematic manner until now. It was found that, sometimes, in situ synthesis methods, using a metal precursor, result in nanocomposites with gold nanoparticles segregated in a subsurface layer of the polymer and/or at the interfaces with the substrate and the atmosphere. Surface nanocomposites have been obtained through completely different approaches, most of the time by chance. One can even question whether these materials are nanocomposites, or, simply, nanoparticles layered on the surface of a polymer, or segregated in a subsurface layer. Their properties, including the sensing capabilities, are completely different from the nanocomposites, having nanoparticles uniformly dispersed in the polymer matrix. The dispersion and organization of nanoparticles in polymer matrices are important to control the properties of nanocomposites. In spite of the efforts to achieve nanocomposites with appropriate morphologies and enhanced surface properties, the control of nanoparticles spatial distribution still remains a challenge. This paper brings together a range of methods that aim to control the formation, growth, and segregation of nanoparticles in polymer films. The diversity of procedures that may result in the formation of surface nanocomposites, some from the authors’ own work, is overviewed in this paper.