Performance improvement by alumina coatings on Y₃Al₅O₁₂:Ce³⁺ phosphor powder deposited using atomic layer deposition in a fluidized bed reactor

Abstract

20To improve the thermal stability, Al 2

Investigation of lanthanum substitution effects in yttrium aluminium garnet: importance of solid state NMR and EPR methods

“…The excitation spectra for emission at 560 nm consist of two broad bands at about 450 nm. These bands correspond to the [Xe]4f → [Xe]5d transitions of Ce 3+ ion [36,37]. As seen, the higher energy band is much weaker than its lower energy counterpart.…”

Dual‐Shelled RbLi(Li3SiO4)2:Eu2+@Al2O3@ODTMS Phosphor as a Stable Green Emitter for High‐Power LED Backlights

“…All the diffraction patterns are indexed to the standard patterns of monoclinic RbLi(Li 3 SiO 4 ) 2 (PDF card No.76‐0344) with a space group of C 2/ m besides very small amounts of Li 4 SiO 4 impurity, indicating these processes do not change the crystallographic structure of the phosphor. There are no diffraction peaks of Al 2 O 3 detected in the XRD patterns of RLSO:Eu 2+ @Al 2 O 3 , which is attributed to the formation of amorphous phase of Al 2 O 3 coating layers . Fourier transformation infrared (FTIR) spectra are used to determine the chemical bond and functional groups present and investigate the surface change of RLSO:Eu 2+ .…”

Atomic layer deposition (ALD) of nanoscale coatings on SrAl2O4‐based phosphor powders to prevent aqueous degradation

“…5. Atomic layer deposition (ALD) is a vapor deposition process that relies upon surface‐limited chemical reactions . ALD usually consists of two sequential half‐reactions on a substrate surface.…”

“…In this paper, we further explore the aqueous degradation of SrAl 2 O 4 ‐based phosphorescent powders and the use of atomic layer deposition (ALD) to deposit nanoscale metal oxide coatings that enhance aqueous durability. While ALD has already successfully been applied to other fluorescent powders to improve durability, it has never been investigated in detail on an aluminate‐based long afterglow phosphor. The wide bandgap oxide materials (Al 2 O 3 , TiO 2 ) and ALD film thicknesses (<15 nm) explored here are commensurate with retaining good optical emission and have shown good stability in other aqueous protection applications …”

“…Atomic layer deposition (ALD) is a vapor deposition process that relies upon surface-limited chemical reactions. [13][14][15][16]19 ALD usually consists of two sequential half-reactions on a substrate surface. In this case, we use a metalorganic and a metal halide as the precursor and water as the coreactant to form a metal oxide thin film.…”