Enhancement effect of terbium complex luminescence by binding to silver nanoparticles in the solution

The luminescent properties of terbium complex (terbium citrate) by binding to silver nanopartilces in the solution have been reported in this paper.The enhanced luminescence of the complex containing silver nanoparticles was observed at a limited particle concentration region.The nanoparticle concentration dependence of the luminescent intensity was regarded as the result of a delicate balance between an enhancing and a quenching effect of the silver nanoparticles.Furthermore,silver nanoparticles also affected the asymmetric ratio (AS) value of terbium luminescence.We discuss the luminescent properties of the terbium complex in terms of the local electromagnetic field,refractive index,and the ligand field around terbium ion.