Laser-induced formation of structures of silver nanoparticles in fluoracrylate films impregnated with Ag(hfac)COD molecules

Methods of absorption spectroscopy and transmission electron microscopy (TEM) are used to study the processes of the laser-induced formation of silver nanoparticles (Ag NPs) in films of fluoracrylate polymers (FAPs) impregnated with Ag(hfac)COD molecules in a medium of supercritical CO2. An observation of the behavior of plasmon resonance (PR) bands in the impregnated FAP samples reveals the presence of a few features in the formation of Ag NPs under exposure to a continuous laser emission in the visible light range. Firstly, the formation of Ag NPs depends on the properties of the matrix (degree of polymerization) and on the power and dose of the laser exposure; its mechanism differs from the thermochemical one. Secondly, only in this case (using TEM) did we find the effect of the formation of periodic layered structures of nanoparticle layers situated inside a film perpendicular to the direction of emission. In addition, while recording the absorption spectra for a long time (a few days) after laser exposure, we revealed the effect of the postradiation growth of PR bands in the samples kept under darkroom conditions at room temperature. The models and formation mechanisms of Ag NPs are discussed for each case under consideration.