Paving the way to the high-performance red phosphor SALON

In this contribution, we report on the newly found red phosphor Sr[Li₂Al₂O₂N₂]:Eu²⁺ (SALON) and the closely related series of phosphors with the composition SrAl_2-xLi_2+xO_2+2x N_2-2x (0.12≤ x ≤ 0.66). The latter compounds can be regarded as unordered variants of SALON exhibiting much broader emissions that can be tuned between 581 nm (x = 0.66) and 672 nm (x = 0.12). These examples impressively illustrate the importance of ordering phenomena for structure property relationships in luminescent materials. With an emission maximum of 614 nm, the ordered SALON phosphor perfectly meets the desired emission maximum stated in the 2016 solid state lighting R&D plan while also exhibiting an ultranarrow emission band (fwhm = 46 nm). This new phosphor has been shown to enable an LER gain of 16 % in a prototype LED, relative to a state of the art CRI90 reference.