Controlled synthesis and tunable upconversion luminescence of NaYF4:Yb3+/Er3+nanocrystals by Pb2+tridoping

NaYF4:Yb3+/Er3+/Pb2+ nanocrystals were prepared by a hydrothermal method. The simultaneous phase and size control of NaYF4:Yb3+/Er3+ nanocrystals with tunable upconversion luminescence was successfully achieved by tridoping with Pb2+ ions. The intensity ratio of 2H11/2/4S3/2 → 4I15/2 to 4F9/2 → 4I15/2 increased with increasing Pb2+ concentration. The upconversion luminescent properties were also investigated.