Modulation of up-conversion luminescence of lanthanide(III) ion co-doped NaYF4 nanoparticles using gold nanorods

Abstract We have investigated the influence of gold nanorods (Au NRs) proximity on the up-conversion luminescence of lanthanide-doped NaYF 4 nanoparticles (NPs). The measurements were performed on two different systems. We used solvent evaporation method to assemble NaYF 4 :2%Tm 3+ , 20%Yb 3+ NPs/Au NRs thin films, and colloidal water blend suspensions of mixed NaYF 4 :2%Tm 3+ , 20%Yb 3+ or NaYF 4 :2%Er 3+ , 20%Yb 3+ NPs with Au NRs. The coupling of the NaYF 4 :2%Tm 3+ , 20%Yb 3+ and NaYF 4 :2%Er 3+ , 20%Yb 3+ NPs emission with the surface plasmon of Au NRs was found to lead to effective modulation of Tm 3+ and Er 3+ ions luminescence. As the result of NPs and Au NRs being in close contact the rate of excitation could be increased, but also quenching by energy transfer and nonradiative relaxation has been observed.