Figure 3From: Shape-controllable synthesis of hydrophilic NaLuF4:Yb,Er nanocrystals by a surfactant-assistant two-phase system FTIR spectra of UCNP samples: (a) IL-UCNPs, (b) Cit-UCNPs, (c) SDS-UCNPs, (d) DDBAC-UCNPs, and (e) PEG-UCNPs. Back to article page