Modeling the influence of silver nanoparticles on the f-f luminescence of the EuEDTA complex in the polyvinylpirrolidone polymer

A theoretical analysis on experimental results previously obtained on the influence of silver nanoparticles in a polyvinylpirrolidone (PVP) polymer film containing a trivalent europium complex with EDTA ligand is made. Depending on the excitation source (at 393 nm with a xenon lamp or at 532 nm with a focused diode laser) the characteristic Eu³⁺ luminescence is observed to be enhanced by factors between 5 and 50. The theoretical analysis presumes a migration process of the EuEDTA complex units towards the silver nanoparticles, during the synthesis of the composite samples, and subsequently the treatment of the competition between local high field gradient effects and Eu³⁺ ion to the silver nanoparticles energy transfer successfully accounts for the observed luminescence enhancement factors.