Hydrothermal Synthesis of β-NaYF4:Yb, Er Nanocrystals with Upconversion Fluorescence Using Tetraethylene Pentamine as Chelating Ligand

Figure 5

Upconverted fluorescence spectra of NaYF₄:Yb, Er nanocrystals prepared under different reaction time (RE/TEPA = 1 : 1; water/ethanol = 1 : 1; 16.7 mmol/L).