Electronic and optical properties of a novel fluoroaluminate red phosphor Cs2NaAl3F12:Mn4+ with high color purity for white light-emitting diodes

In this work, a novel fluoroaluminate red phosphor of Cs2NaAl3F12:Mn4+ with excellent color purity was fabricated via the introduction of Mn4+ in octahedral center. The crystal and electronic structure, luminescence properties and optical performances were characterized and investigated in detail. Evidences show that Cs2NaAl3F12:Mn4+ is well crystallized into single-phase with particulate morphology, and the non-equivalent occupation in Cs2NaAl3F12 brings about the sharp red emissions with improved color purity upon blue light illumination. For solid-state lighting, the optical parameters made from “blue-yellow-red” contributions is significantly improved to a high color-rendering index of 88.7 and a low color temperature of 3856 K, indicating the potential use of Cs2NaAl3F12:Mn4+ for warm white light-emitting diode applications.