On the crystal structure and luminescence characteristics of a novel deep red emitting SrLaScO₄:Mn⁴⁺

A novel Mn⁴⁺ activated SrLaScO₄ was synthesized and investigated for its crystal structure and optical characteristics. SrLaScO₄ exhibits a well-known K₂NiF₄ structure, it crystalizes in Abma space group and provides an octahedral site of ScO₆ which was exploited for Mn⁴⁺ incorporation. The synthesized phosphor showed broad excitation bands and an uncommon narrow emission band centered at 690 nm with an full width at half maximum (FWHM) of ∼35 nm. The optimal activator ion concentration for SrLaScO₄:Mn⁴⁺ was found to be ∼0.8 mol%. The photoluminescence and photoluminescence excitation characteristics indicate that it can be opted as red emitting material for the white LEDs for indoor agriculture where the deep red emissions are favored. However the tendency of luminescence quenching in the phosphor is very high and ∼85% of original intensity is damped with a temperature rise of 150°C.