Photoluminescence Properties of Sm3+-Doped La2O3 Powders

Abstract

The Sm3+-Doped La2O3powders were prepared by precipitation method. The room temperature photoluminescence (PL) spectra of Sm3+-Doped La2O3powders doped with different Sm3+concentration excited at 405 nm have been investigated. The PL spectra showed three main strong emissions peaks at near 572, 613, and 657 nm, which were due to the f-f forbidden transitions of the 4f electrons of Sm3+, corresponding to4G5/2→6H5/2(572 nm),6H7/2(613 nm), and6H9/2(657 nm), respectively. The optimum Sm3+concentration in La2O3powders for optical emission was determined to be 2.0 %. Since the 2% Sm-doped La2O3 offer a rather strong f–f transition excitation in near the UV region, the as-prepared phosphors are likely to be used as potential red phosphors for near-ultraviolet (370-410 nm) light-emitting diodes (LEDs).