Electronic and optical properties of a novel fluoroaluminate red phosphor CsNaAlF:Mn with high color purity for white light-emitting diodes.

In this work, a novel fluoroaluminate red phosphor of CsNaAlF:Mn with excellent color purity was fabricated via the introduction of Mn in the octahedral center. The crystal and electronic structures, luminescence properties and optical performances were characterized and investigated in detail. The evidences showed that CsNaAlF:Mn well-crystallized into a single phase with particulate morphology, and the non-equivalent occupation in CsNaAlF resulted in sharp red emissions with improved color purity upon blue light illumination. For solid-state lighting, the optical parameters consisted of the "blue-yellow-red" contributions significantly improved to a high color-rendering index of 88.7 and a low color temperature of 3856 K, indicating the potential use of CsNaAlF:Mn for warm white light-emitting diode applications.