Mn-doped Ca14Al10(Zn,Mg)6O35: A deep-red oxide phosphor with high photoluminescence quantum yield and thermal stability

Abstract

Mn-activated oxides have been widely regarded as a new class of red phosphors, while the weak absorption of blue light, low quantum yield (QY), and insufficient thermal quenching performance limit their applications. In this study, a series of deep-red emitting Ca14Al9.8Zn6−xMg0.1+xMn0.1O35 phosphors with outstanding luminescence performances are fabricated, and their optical and vibrational properties, as well as the thermal quenching mechanism, are investigated. The partial substitution of Mg for Zn not only greatly improves the absorption capability of blue light, but also suppresses the crystal defects, resulting in high QY (85.9% with excitation at 460 nm) and low thermal quenching effect (the emission intensity remains ~99.2% at 460 K and ~60.8% at 580 K relative to that at 300 K). This work demonstrates the great potential applications of Ca14Al9.8Zn6−xMg0.1+xMn0.1O35 phosphors in LED devices.