Water-dispersible Re3+ doped CeF3 colloidal nanocrystals with well controllable morphology and high crystallinity have been successfully synthesized through a solvothermal process. The TEM images illustrate that the Re3+ doped CeF3 nanocrystals are rectangular (or cubic) with a mean diameter of ~10 nm. The excellent dispersibility in some of the polar solvents including water is achieved by using polyethyleneimine as the capping agent. The amine groups of the polymer chains on one hand bind to the nanocrystal surface; on the other hand the free ones could link to functional materials including bio-molecules. The CeF3 nanocrystals doped with Tb3+ and Dy3+ions show the characteristic emission of Tb3+ 5D4–7FJ (J = 6–3, with 5D4–7F5 green emission at 542 nm as the strongest one) and Dy3+ 4F9/2–6H15/2 (blue-green color at 478 nm) and 4F9/2–6H13/2(yellow color at 571 nm) transitions, respectively. The energy transfer from Ce3+ to Tb3+ and Dy3+was also investigated in detail. In vitro studies of Re3+ doped CeF3 colloidal nanocrystals on HepG2 cells confirm their excellent biological compatibility. The obtained solid CeF3:Tb3+/PDMS nanocomposites are very stable and flexible and exhibit strong green photoluminescence upon UV excitation.
A facile synthesis and photoluminescence properties of water-dispersible Re3+ doped CeF3 nanocrystals and solid nanocomposites with polymers