Selective preparation of Ag species on photoluminescence of Sm3+ in borosilicate glass via Ag+-Na+ ion exchange

Photoluminescence (PL) of rare earth ion-doped glasses could be enhanced by diverse Ag species such as Ag+ ions, Ag+-Ag+ pairs, Ag nano-clusters (NCs), and Ag nanoparticles (NPs). Selective preparation of silver species in rare earth ion-doped glasses is a crucial step to obtain the luminescence enhancement of rare earth ions caused by the different silver species. In this work, Ag+ ions and Ag NCs were selectively prepared in the Sm3+-doped borosilicate glass via the Ag+-Na+ ion exchange. The influence of AgNO3/NaNO3 ratio in the molten salt on the Ag existing states was investigated. The results demonstrate that the isolated Ag+ ions exist in the Sm3+-doped borosilicate glass when the ratio of AgNO3/NaNO3 is 1/1000. The Ag NCs are formed in the Sm3+-doped borosilicate glass when the AgNO3/NaNO3 ratio is 1/10. The influence of Ag+ ions or Ag NCs on the PL of Sm3+ was systematically investigated. The results show that the PL of Sm3+ was enhanced by the energy transfer from Ag+ ions or Ag NCs to Sm3+.