Tunable energy transfer between [Au(CN)2-]n 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.

Graphical abstractWe report energy transfer between dicyanoaurate(I) luminescent nanocluster donor ions and Tb3+ and Eu3+ acceptor ions in aqueous solutions. The f-f transition emissions of Tb3+ ions shown above are intensified by increasing the donor's concentration. However, Eu3+ ions quench the donor's emission without intensification of the f-f transition emissions.Download full-size image