Li2TiO3:Mn4+ Deep-Red Phosphor for the Lifetime-Based Luminescence Thermometry

摘要

Luminescence of monoclinic lithium metatitanate (Li2TiO3) powders activated with different quantities of Mn4+ is studied in detail. Its strong deep-red emission arising from the Mn4+ 2 Eg ! 4 A2g spin forbidden transition is centered at around 688 nm and is suitable for luminescence thermometry. Structural and electron paramagnetic resonance analyses show that Mn4+ ions are equally distributed in two almost identical Ti 4+ sites in which they are octahedrally coordinated by six oxygen ions.