Photoluminescence Properties of Layered Perovskite-Type Strontium Scandium Oxyfluoride Activated With Mn4+

Abstract

In this research, we have found that layered perovskite titanate Sr2TiO4 doped with Mn4+ exhibits photoluminescence even at room temperature despite no luminescence from Mn4+-doped SrTiO3 with a three-dimensional bulky perovskite structure. The relative position of t2g orbital of Mn to the valence band is a key factor for appearance of Mn4+-emission in Sr2TiO4:Mn. This result suggested usefulness of layered perovskite-type materials as hosts for Mn4+-activated phosphors than the bulky perovskite-type materials. Our investigation into photoluminescence of Mn4+-doped layered perovskite compounds has revealed that strontium scandium oxyfluoride Sr2ScO3F activated with Mn4+ exhibits Mn4+-emission with a peak at 697 nm under excitation at 300–600 nm and its emission intensity is much stronger than that of Sr2TiO4:Mn. The internal and external quantum yields of Sr2ScO3F:Mn were determined to be 50.5 and 43.5% under excitation at 345 nm, respectively.

Crystal Structure, Characterization, and Luminescence Properties of Mn4+‐Doped K3Nb2O4F5

“…However, there are examples for which the opposite is true, e.g. Sr 2 ScO 3 F [23] and Mg 28 Ge 7.5 O 38 F 10 [24] . Adachi also noted this in a review paper from 2020, where he categorized Mn 4+ ‐activated phosphors into a variety of different groups based on their photoluminescence (PL) and photoluminescence excitation (PLE) spectra [4] …”

Strong sensitivity enhancement in lifetime-based luminescence thermometry by co-doping of SrTiO3:Mn4+ nanocrystals with trivalent lanthanide ions

“…Therefore, due to the difference in the effective ionic radii and in the coordination number mainly the Mn 4+ ions in the Ti 4+ position are observed in the SrTiO 3 structure. 33,[43][44][45][46] Additionally Mn 4+ as a 3d 3 ion is thermodynamically extremely stabilized in the octahedral fields. On the other hand, the presence of Mn 2+ in the Sr 2+ sites in SrTiO 3 was reported by e.g.…”

Advance in Red-emitting Mn4+-activated Oxyfluoride Phosphors

“…L i a n g 等 [ 2 8 ] 用 水 热 和 离 子 交 换 法 制 备 了 [27] Fig. 7 Unit cell of Sr 2 ScO 3 F (a) and temperature-dependent emission spectra of Sr 2 ScO 3 F:Mn 4+ (b) [27] Sr: yellow; Sc: blue; O: red; F: gray 图 8 BaTiOF 4 :Mn 4+ 的室温激发与发射光谱(a), BaTiOF 4 :Mn 4+ 的室温和低温发光光谱(b), BaTiOF 4 的晶胞(c)和[Ti 2 OF 4 ]畸 变八面体(d) [28] Fig.…”

“…L i a n g 等 [ 2 8 ] 用 水 热 和 离 子 交 换 法 制 备 了 [27] Fig. 7 Unit cell of Sr 2 ScO 3 F (a) and temperature-dependent emission spectra of Sr 2 ScO 3 F:Mn 4+ (b) [27] Sr: yellow; Sc: blue; O: red; F: gray 图 8 BaTiOF 4 :Mn 4+ 的室温激发与发射光谱(a), BaTiOF 4 :Mn 4+ 的室温和低温发光光谱(b), BaTiOF 4 的晶胞(c)和[Ti 2 OF 4 ]畸 变八面体(d) [28] Fig. 8 Excitation and emission spectra of BaTiOF 4 :Mn 4+ at room temperature (a), emission spectra of BaTiOF 4 :Mn 4+ at 77 K and 293 K (b), unit cell of BaTiOF 4 (c), and distorted octahedron coordination of [Ti 2 OF 4 ] (d) [28] Ba: yellow; Ti: blue; O: red; F: gray [29] 。 六种 Mg 2+ 格位都形成八面体配位, 但其成键情况不 同, 分别为: [29] 。Mn 4+ 取代 Ge 4+ 时 为等价取代, 而取代 Mg 2+ 时需产生间隙阴离子或阳 离子空位等进行电荷补偿。Brik 等 [29] 通过电荷交换 模型研究了 Mn 4+ 在 Mg 28 Ge 7.55 O 32 F 15.04 的倾向占据 格位: [29] , 其热猝灭温度高达 700 K, 远高于 K 2 SiF 6 :Mn 4+ 荧光粉 558 K 的热猝灭温度 [34] 。在 [29] Fig.…”