Effects of activated Sr ²⁺ ion content on strong blue‐emitting Ca ₂ Sb ₂ O ₇ materials for high‐quality WLED devices

Abstract

Summary In this report, the luminescent performances of the self‐host blue‐emitting Ca2Sb2O7 materials were investigated in terms of the sintering temperature and the dopant Sr2+ ion content. The emission intensity was enhanced with an increase of the sintering temperature as well as the lattice parameters. After doping the Sr2+ ions (>1.2 mol%), the emission spectra of Ca2Sb2O7 materials would be redshifted. The blue‐emitting color (Ca2Sb2O7) turned into greenish‐blue (Sr2+@1.6 mol%) and green (Sr2+@2 mol%) colors in sequence. In light of these interesting findings, the crystal structure, elemental composition, morphology, thermal stability, luminescent dynamics, luminescent efficiency, etc were investigated and compared. Finally, the mini‐white lighting‐emitting diodes (WLEDs) based on the blue‐emitting Ca2Sb2O7, greenish‐blue‐emitting Ca0.4Sr1.6Sb2O7, and green‐emitting Sr2Sb2O7 phosphors were fabricated by mixing commercial phosphors (CP). Especially, the Ca2Sb2O7‐CP‐WLED and Sr2Sb2O7‐CP‐WLED devices exhibited a warm white light with good correlated color temperature (<3200 K) and excellent color‐rendering index (>88). All the above results suggested that the self‐host emitting materials of Sr2+ activated Ca2Sb2O7 with color‐tunable properties could be very promising for solid‐state lighting applications.

Deep-red-emitting phosphors of Mn4+-activated tantalite for high-sensitivity lifetime thermometry and security films

“…[1][2][3][4][5][6][7][8] Generally, common commercial pc-WLEDs are fabricated by applying high-efficiency rareearth (RE)-doped materials (i.e., Y 3 Al 5 O 12 :Ce 3+ , Y 2 O 2 S:Eu 3+ , (Sr, Ca)AlSiN 3 :Eu 2+ , BaMgAl 10 O 17 :Eu 2+ , and (Ba,Sr) 2 SiO 4 :Eu 2+ ) onto near-ultraviolet (NUV) or blue LED chips. [9][10][11][12][13] However, they suffered from high manufacturing cost due to expensive and deficient RE resources, which might be not good enough from an economic perspective. In light of this limitation, there is great demand for exploring good potential candidates with a high performance and a lower price.…”