Fabrication of Electroluminescent Devices Using Nanocrystalline Oxide Phosphors

Nanosized Y2O3:Eu3+ crystalline powders with average particle sizes around 100 nm, measured by field-emission scanning electron microscopy (FE-SEM), have been synthesized by a polymerized precursor method using carboxymethyl cellulose (CMC). The nanocrystalline phosphors exhibit intense photoluminescence (PL) and cathodoluminescence (CL) around 612 nm, being attributed to the 5D0-7F2 transition of Eu3+. Electroluminescence (EL) properties of the nanophosphors in the form of thick films were investigated, and emission of red light with maximum intensity at 612 nm (corresponding to x = 0.57 and y = 0.32 in the CIE chromaticity diagram) was observed under high ac field at 1 kHz. The obtained results suggest a possibility that Y2O3:Eu3+ nanopowders can be used as a red-emitting phosphor for EL devices.