Far‐Red‐Emitting BiOCl:Eu ³⁺ Phosphor with Excellent Broadband <scp>NUV</scp> ‐Excitation for White‐Light‐Emitting Diodes

Abstract

Rare‐earth ion‐doped semiconducting phosphor has attracted extensive attention due to the ability to achieve efficient luminescence through the host sensitization. Here, we present a new type red‐emitting Eu 3+ ‐doped BiOCl phosphors possessing a broad excitation band in the near‐ultraviolet ( NUV ) region. Experimental measurements and theoretical calculations confirm that Eu 3+ ion dopants result in forming impurity energy level near valence band, and the excellent broadband NUV ‐exciting ability of Eu 3+ ion is due to the electronic transitions of BiOCl band gap. Moreover, the highest emission intensity of the phosphors is from the 5 D 0 → 7 F 4 transition of Eu 3+ around 699 nm (far‐red) through whether host excitation or direct Eu 3+ ions excitation, which lie in the particular structure of BiOCl crystals. Our results indicate that the Eu 3+ ‐doped BiOCl crystals show great potential as red phosphors for white‐light‐emitting diodes.