Sr<sub>2</sub>BN<sub>2</sub>Cl:Eu<sup>2+</sup>-Based Narrow-Band Blue-Emitting Phosphor: A Potential Color Converter for Illumination and Displays
Haoyang Wang, Zebin Li, Runtian Kang, Ruijie Ji, Yuhua Wang
Abstract
Due to the wide range of uses for phosphors in lighting and displays, research on narrow-band luminescent phosphors has recently received significant interest. In this work, Eu2+-activated Sr2BN2Cl phosphor has been successfully synthesized. Sr2BN2Cl:Eu2+ shows a wide absorption band in the UV region and exhibits a narrow-band emission peaking at 450 nm with a full width at half-maximum of ∼60 nm. More significantly, excellent thermal stability was discovered, which showed it still retained 87.4 and 100% of room-temperature intensity at 150 and 250 °C, respectively. The rigid skeleton formed by the co-edge connection of Sr(N, Cl)6 octahedra and defects in the crystal are responsible for the excellent thermal stability of the phosphor. In addition, two types of white-led devices have been prepared to test this phosphor for illumination and display applications. The former shows low correlated color temperature (CCT = 3190 K) and a high color rendering index (CRI = 92.0). The latter shows that using Sr2BN2Cl:Eu2+, β-sialon:Eu2+, and K2SiF6:Mn4+ together for backlit displays can cover 73.3% of the NTSC area, which is comparable to commercial BaMgAl10O17:Eu2+ phosphors. These findings suggest that the blue phosphor Sr2BN2Cl:Eu2+ will be a promising choice for lighting and backlight displays.