Temperature dependence of structural and luminescence properties of Eu3+-doped Y2O3 red-emitting phosphor thin films by pulsed laser deposition

Abstract

Pulse laser deposition was used to obtain nanocrystalline red-emitting Y 2 O 3 :Eu 3? thin-film phosphors. X-ray diffraction measurements show that the un-annealed thin film was amorphous, while those annealed were crystalline. At lower annealing temperature of 600-700°C, cubic bixbyite Y 2 O 3 :Eu 3? was formed. As the annealing temperatures were increased to 800°C, hexagonal phase emerged. The average crystallite size of the film was 64 nm. Photoluminescence measurement indicates intense red emission around 612 nm due to the 5 D 0 ? 7 F 2 transition. Scanning electron microscopy indicated that agglomerates of noncrystalline particles with spherical shapes were present for the un-annealed films. After annealing at high temperature, finer morphology was revealed. Atomic force microscopy further confirmed the formation of new morphology at the higher annealing temperatures. UV-Vis measurement indicated a band gap in the range of 4.6-4.8 eV. It was concluded that the annealing temperature played an important role in the luminescence intensity and crystallinity of these films.

Pr3+-doped Y2O3 nanocrystals embedded in Y2O3 thin films as a sandwich-like structure prepared by pulsed laser deposition

“…Furthermore, these composite films represent an additional solution to the limitation of RE doping concentration in glasses related to low solubility rates and strong tendency to form clusters, which ultimately leads to fluorescence quenching [20,21,22]. In this context, several methods are available to prepare these composite films, such as laser molecular beam epitaxy [23,24], spin coating [25,26], spray pyrolysis [27,28], radio frequency magnetron sputtering [29,30], or pulsed laser deposition (PLD) [31,32,33]. Among these, PLD represents a promising technology that provides a remarkable stoichiometric transfer from a pre-pressed solid target to the so-obtained thin film on a substrate.…”

Luminescence Properties of a Yellow-Reddish Emitting SiO2/REFP @SAOED Long-Lasting Phosphorescent Composite Obtained via Sol-Gel Coating Technology

“…Therefore, LLP materials with high luminescence intensity and warm emitting color or even red color have attracted a great deal of attention. After several years of efforts, several kinds of LLPs whose phosphorescent color is located at warm color region have been successfully prepared, such as the yellow-emitting Ca 6 BaP 4 O 17 :Eu 2+ ,Ho 3+ , 1 orange-yellow emitting Ca 2 Si 5 N 8 :Eu 2+ , Tm 3+ , 2,3 the reddish-orange emitting Zn 2 P 2 O 7 :Sm 3+ , Li + , 4 and the red-emitting CaTiO 3 :Eu 3+ , 5 AlN: Mn 2+ , 6 Y 2 O 2 S:Eu 3+ , Zn 2+ , Ti 4+ , 7 Sr 4 Al 14 O 25 :Eu 3+ . 8 However, the luminescence intensity of these warm colored luminescent materials is too low compared with the SAOED, and the duration of the afterglow is less than 2 hours, which can't satisfy the commercial application requirement.…”

“…9,10 As is well-known, the SAOED is a kind of light energy absorption-storage-release LLP material, which can absorb the sun light energy and store this energy in the lattice. 11,12 Once the excitation light is removed, the light energy will gradually release out in the form of bright visible luminescence with green color, which is due to the characteristic 4f 6 5d 1 to 4f 7 transition of Eu 2+ ions that doped in the substrate of SAOED. 13 Besides, it is well known that fluorescence pigment (FP) can be excited by some certain lights with certain wavelength and then emit fluorescence with a certain color due to some special chemical groups in the molecular structure of the FP, such as the chromophore or auxochrome groups, carbonyl, azo z E-mail: ge_mingqiao@126.com and carbon-nitrogen bonds.…”