A novel double-perovskite Gd₂ZnTiO₆:Mn⁴⁺red phosphor for UV-based w-LEDs: structure and luminescence properties

Abstract

This work highlights a novel double-perovskite red phosphor Gd2ZnTiO6:Mn4+for UV-based warm white LEDs.

Formation mechanism and optimized luminescence of Mn4+‐doped unequal dual‐alkaline hexafluorosilicate Li0.5Na1.5SiF6

“…The excitation and emission spectra, and the decay curves of the red phosphor LNSF:Mn measured at 78 and 298 K are shown in Figure . The two excitation bands peaking at 370 and 470 nm in the excitation spectra monitored at 620 nm are due to the 4 A 2g → 4 T 1g and 4 A 2g → 4 T 2g transitions of Mn 4+ according to the Tanabe‐Sugano diagram for Mn 4+ , which are consistent with the reported results of other Mn 4+ activated fluoride compounds . The maximum excitation band locating in blue region indicates that the red phosphor LNSF:Mn shows great promise in GaN based WLEDs.…”

“…For Mn 4+ ‐doped red phosphors with host lattice of complex oxides, repeated high‐temperature sintering procedures are required in their synthesis process. Furthermore, the red phosphors of Mn 4+ ‐doped complex oxides often show deep red luminescence and their emission spectra are located in near IR region (>650 nm) which are not insensitive to naked eyes …”

“…Furthermore, the red phosphors of Mn 4+ -doped complex oxides often show deep red luminescence and their emission spectra are located in near IR region (>650 nm) which are not insensitive to naked eyes. [12][13][14][15][16][17][18] Mn 4+ -doped fluorides exhibit superior luminescence performance with ideal chromaticity ordinations and ease of operation. A series of red phosphors A 2 XF 6 :Mn 4+ and A 3 YF 6 : Mn 4+ (A is one type of alkaline ions, such as K, Na, Rb, or Cs; X is Si, Ge, or Zr; Y is Al or Ga) have been obtained by simple synthetic processes at room temperature.…”

Rare‐earth‐free Li5La3Ta2O12:Mn4+ deep‐red‐emitting phosphor: Synthesis and photoluminescence properties

“…E without is the emission spectra of the excitation light, recorded with the equipment blank sample in place. Here, The QE value of LLTO:0.4 mol% Mn 4+ phosphor is ~38.6%, which is close to that of Gd 2 ZnTiO 6 :Mn 4+ (~39.7%) 52 and larger than those of Mn 4 +-doped luminescence materials, such as Ca 2 LaTaO 6 :Mn 4+ (~34.6%), 22 Ba 2 TiGe 2 O 8 :Mn 4+ (~35.6%), 53 and Mg 2 La 2 SnO 7 :Mn 4+ (~28.55%). 54 Tanabe-Sugano energy level diagram of Mn 4+ ion in the octahedron is depicted in Figure 3B.…”

Tunable Eu2+ emission in KxNa1−xLuS2 phosphors for white LED application

“…Furthermore, there is the intensive research aiming to find efficient red phosphors to construct white LED based on near-ultraviolet (UV) LED chips coated with RGB tri-color phosphors. However, many suffer from very low excitation efficiency in near UV part of the spectrum, see for example [22][23][24][25]. Nowadays, the garnets are probably the most widely used [26][27][28][29][30][31][32][33].…”