New Photonic Materials based on Ag Nanoparticles Modified with Stilbene Dyes and Its Peculiar Behavior Studied with SERS

In the recent years, there has been a growing interest in development of smart photoactive materials with variable properties. This work presents the SERS study of behaviour of organometallic composites obtained by modification of Ag nanoparticles in hydrosols with several amino derivatives of stilbene. The feasibility of bifunctional stilbenes to be the molecular linkers of Ag nanoparticles is discussed. The hot spots activity of such modified Ag nanoparticles is considered. Two exciting but not fully understood finding were made: i) tertiary amines can be used as the effective molecular linkers; ii) the structure of central fragment between two benzyl rings has a strong influence on the modifier ability to incorporate the Ag nanoparticles into agglomerates with hot spots. The limitations consisting in the pH value and the presence of chloride ions are described for a potential application of the developed hot spots substrates.