Simultaneous energy transfer from molecular-like silver nanoclusters to Sm3+/Ln3+ (Ln = Eu or Tb) in glass under UV excitation

Molecular-like silver nanoclusters (ML-Ag NCs) with size dependent tunable luminescence properties and high-quantum yield has been explored as a new type of sensitizer for rare earth (RE) ions in glasses recently. In this research, the borosilicate glasses containing ML-Ag NCs and RE3+ (RE = Sm, Eu, Tb) ions were prepared with melt-quenching method. The absorption, TEM and steady spectra measurements indicated that compare with Sm3+ and Tb3+, the introduction of Eu3+ can more effectively promote the formation of luminescent ML-Ag NCs and their further aggregation. Besides the predictable efficient energy transfer from ML-Ag NCs to a single type of RE3+ ion in the codoped glasses, the simultaneously sensitization of Sm3+/Eu3+ and Sm3+/Tb3+ couples by ML-Ag NCs were further realized in the tri-doped glasses. Benefited from the excitation wavelength dependence of energy transfer from ML-Ag NCs to Sm3+/Eu3+ and Sm3+/Tb3+ couples and excitation efficiency on ML-Ag NCs and RE3+ ions, the tri-doped glasses exhibit broad tunable emission simply by changing the excitation wavelength, and the white light emission was achieved in GAgSmEu under UV excitation.