High color purity aluminate phosphor SryCa1-x-yAl12O19: xEu2+ for lighting and backlight display applications

In the context of the rapid advances in electronic information technology, the advancement of novel high-efficiency narrow-band blue phosphors represents a pivotal step in the advancement of high-quality liquid crystal displays (LCDs), as well as the development of white light-emitting diodes (WLEDs) with a reduced correlated color temperature (CCT). In this study, based on the sensitivity of Eu 2+ emission to local environment, the alkaline earth aluminate material CaAl 12 O 19 with high structural symmetry was selected as the matrix, and the symmetry of crystal structure was improved by replacing Ca 2+ with Sr 2+ , the narrow-band emission of the phosphor is realized. The Sr 0.9 Ca 0.09 Al 12 O 19 : 0.01Eu 2+ (SCAO: Eu 2+ ) phosphor exhibited narrow-band emission with the full width at half maximum (FWHM) of 45.76 nm, and the colour purity of up to 95.46 %. Moreover, the internal quantum efficiency (IQE) of SCAO: Eu 2+ has been demonstrated to reach 81.70 %. In addition, SCAO: Eu 2+ phosphor, (Ba, Sr) 2 SiO 4 : Eu 2+ phosphor, CaAlSiN 3 : Eu 2+ phosphor, and 275 nm UVLED chips were combined to prepare white LED devices exhibiting a low color temperature (3733 K). The three-band LEDs of SCAO: Eu 2+ , β-Sialon: Eu 2+ and K 2 SiF 6 : Mn 4+ exhibited a colour gamut covering 84.75 % of the National Television Standards Committee (NTSC) standard. This indicates that the phosphor possesses the characteristics of a highly effective narrow-band blue-light-emitting substance with considerable potential for utilization in lighting and backlighting displays.