Tunable energy transfer between luminescent nanoclusters and rare earth ions in aqueous solution

Energy transfer has been studied between dicyanoaurate(I) luminescent nanocluster donor ions and Tb3+ and Eu3+ acceptor ions in aqueous solutions with steady-state luminescence at room temperature. The f–f transition emission intensities of Tb3+ ions can be sensitized and enhanced by varying the dicyanoaurate(I) donor ion’s concentration, due to the formation of different excimer and exciplex nanoclusters. However, the f–f transition emission intensities of Eu3+ ions are not enhanced but the donor’s emission is quenched thorough a non-radiative charge transfer pathway. The Stern–Völmer constants show different quenching efficiencies for different nanoclusters of the donor.