Light emitting nanoparticles
Luminescent materials are found in everyday life in television sets, computer screens, fluorescent lamps and lasers. Luminescent materials also called phosphors are solid compounds which convert certain types of energy into electromagnetic radiation usually in the visible range.
Europium-doped yttria (Y2O3:Eu3+) with a cubic crystal phase is one of the most often used red emitting phosphors (excitation with UV-light) and applied in fluorescent lamps and plasma display panels. New ideas regarding high resolution displays have increased the interest into using nanosized Y2O3:Eu3+ particles over the latest few years.
Cubic Y2O3:Eu3+ nanoparticles (<30 nm) were prepared by flame spray pyrolysis (FSP) . The crystal size and composition could be closely controlled from monoclinic to cubic by selecting the FSP-process parameters that determine the high temperature particle residence time. These nanosized flame-made particles showed lower PL intensities than a commercial phosphor but prolonged radiative decay.
Recent, relevant references:
- A. Camenzind, R. Strobel, S. E. Pratsinis, Cubic or monoclinic Y2O3:Eu3+ nanoparticles by one step flame spray pyrolysis, Chem. Phys. Lett., 415, 193-197 (2005).
- A. Camenzind, R. Strobel, F. Krumeich, S.E. Pratsinis, Luminescence and crystallinity of flame-made Y2O3:Eu3+ nanoparticles, Adv. Powder Technol., accepted (2006).