Formal kinetics of growth of nanosized silver particles upon silver nitrate reduction with sodium citrate in a reverse micellar solution of AOT

The growth kinetics of silver nanoparticles upon silver(I) reduction with sodium citrate in an aqueous solution solubilized to a reverse micellar solution of sodium bis(2-ethylhexyl) sulfosuccinate in decane is studied spectrophotometrically under constant conditions of irradiation of the reaction mixture with visible light. The formal kinetics of the process corresponds to an autocatalytic mechanism. The effective rate constants of growth of silver nanoparticles, unlike those of gold nanoparticles, are independent of the size of the inner micellar cavity when its radius changes from 2 to 6 nm. This is most likely due to a great effect of the photochemical factor or Ag⁺ localization in the inner surface layer of the micelles on the rate constants.