Holographic recording with polymer nanocomposites containing silver nanoparticles photogenerated in situ by the interference pattern

A process allowing in situ photochemically assisted synthesis of silver nanoparticles (NPs), in a polymerizable acrylic formulation was developed and the photopolymerization of this formulation was studied. It was found that the presence of NPs does not perturb the polymerization process in the least, making it possible to fabricate metal/polymer nanocomposites by a one-step-one-pot photochemical process. The size distribution of NPs was very narrow and their size could be controlled by the chemical parameters of the reactive formulation. This system was used to record holographic gratings and it was observed that both the holographic sensitivity and the diffraction efficiency at maximum were significantly improved in the presence of particles. Moreover, TEM analysis (Figure 1) revealed a clear-cut segregation of photochemically generated NPs between dark and bright regions of the incident pattern, thus demonstrating the possibility to manipulate nascent particles with light gradients.