Luminescence Properties of a Red Phosphor, CaAlSiN[sub 3]:Eu[sup 2+], for White Light-Emitting Diodes

TLDR

We developed a new red phosphor CaAlSiN₃:Eu²⁺ with a broad excitation band extending from the UV region to the visible. At optimal Eu concentration, the phosphor delivers sevenfold higher quantum output than conventional red phosphors, remains more efficient across all excitation wavelengths, shows high room‑temperature efficiency due to minimal thermal quenching from a rigid network of tetrahedra, is chemically stable, and is a promising material for warm‑white LEDs.

Abstract

We developed a new red phosphor, , which has a broad excitation band extended from UV region to . At the optimum Eu concentration of , quantum output is seven times higher than for a conventional red phosphor, , under excitation. The phosphor is also more efficient than or at any excitation wavelength. One reason of the high room-temperature efficiency is small thermal quenching, which is probably related to a rigid network of and tetrahedra. The phosphor is chemically stable as well. Accordingly, it is a promising material for warm-white light-emitting diodes.