Types Of Silver Nanoparticles Research Articles

Inner wall coated hollow core waveguide sensor based on double substrate surface enhanced Raman scattering

A hollow core waveguide with silver nanoparticles coated on the inner wall has been used for molecular detection based on surface enhanced Raman scattering (SERS). With rhodamine 6G as an analyte molecule and two types of silver nanoparticles as double SERS substrates, the inner wall coated hollow core waveguide (IWCHCW) exhibits higher sensitivity than previous sampling methods with only one substrate. The improvement of sensitivity is attributed to the additional enhancement of the electromagnetic field by double substrate “sandwich” structure. The simple architecture and high sensitivity of IWCHCW make it promising for molecular detection in various analytical and sensing applications.

Thermochemicstry of the oxidative dissolution of silver nanoparticles in AOT reverse micelles

A procedure has been developed for thermochemical studies of two types of silver nanoparticles: coagulated nanoparticles in isolated nanopowders and unbound nanoparticles enclosed in micelles. The first type of nanoparticle was obtained and studied after destroying micelles. The heats and rates of dissolution of unbound nanoparticles (i.e., nanoparticles enclosed in micelles and involved in Brownian motion together with the latter) were determined by reacting them with nitric acid solubilized in micelle systems of the same composition. The heats of solution of Ag0 in HNO3 found for isolated nanopowders were −10 × (1 ± 0.3) kJ/mol; they were close to the results obtained for bulk samples under the same conditions. The heats of solution of nanoparticles in micelles were estimated at −(17–25) kJ/mol. The dissolution rates of silver nanoparticles in micelles as functions of micelle composition were two to three times the dissolution rates of isolated nanopowders.