Limits...
Green-Emitting Gd 3 Ga 5 O 12 : Tb 3+ Nanoparticles Phosphor: Synthesis, Structure, and Luminescence

View Article: PubMed Central - PubMed

ABSTRACT

Nano- and microceramics of Gd3Ga5O12 garnet doped with 1 mol % Tb3+ ions were synthesized via co-precipitation and high-temperature solid-state reaction methods. X-ray diffraction measurements confirmed the formation of the garnet structure with Ia3d space group in all investigated samples. Atomic force microscopy surface images and grain-size distribution diagrams of Gd3Ga5O12: 1 mol % Tb3+ nanoceramics with 300 and 400 g/mol of polyethylene glycol (PEG) were obtained. The relationship between the content of polyethylene glycol and the particle size of Gd3Ga5O12: Tb3+ phosphors was revealed. An intense broad band (λm = 266 nm) related to spin-allowed 4f8-4f75d1 transitions of Tb3+ ions was found in photoluminescence excitation spectra of Gd3Ga5O12: Tb3+ nanocrystalline ceramics with PEG-300 and PEG-400 at 300 K. The broad excitation band caused by spin-forbidden (λm = 295 nm) 4f-5d transitions in Tb3+ ions was additionally observed in the photoluminescence excitation spectra of Gd3Ga5O12: Tb3+ microceramics. Emission of Tb3+ ions under X-ray and UV excitations is presented by two groups of sharp lines which correspond to 5D3 and 5D4 → 7Fj transitions of Tb3+ ions with the most intense line at 546 nm (5D4 → 7F5). It was established that the increasing of PEG content leads to the decreasing of the X-ray and photoluminescence emission intensities.

No MeSH data available.


Photoluminescence emission spectra of Gd3Ga5O12: 1 mol % Tb3+ nano- (a) and microceramics (b) at 266-nm excitation obtained at room temperature
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC5383918&req=5

Fig8: Photoluminescence emission spectra of Gd3Ga5O12: 1 mol % Tb3+ nano- (a) and microceramics (b) at 266-nm excitation obtained at room temperature

Mentions: Photoluminescence emission spectra of Gd3Ga5O12: 1 mol % Tb3+ nano- and microceramic samples obtained at room temperature are shown in Fig. 8. A number of sharp intense lines were found in 350–650-nm spectral regions. These lines correspond to 5D3 (5D4) → 7Fj transitions in Tb3+ ions. Sharp weak lines with a maximum at 384, 420, and 440 correspond to 5D3 → 7F6, 5D3 → 7F5, and 5D3 → 7F4 transitions, respectively [1, 9, 10]. It should be noted that samples activated with 1 mol % Tb3+ ions reveal relatively high emission in a green spectral region. Luminescence lines in the spectral range of 480–650 nm with maxima at 491 nm (5D4 → 7F6), 546 nm (5D4 → 7F5), 597 nm (5D4 → 7F4), and 633 nm (5D4 → 7F3) are observed at longer wavelengths. Emission lines of 5D3 and 5D4 levels are associated with weak electron-vibrational transitions in Tb3+ ions [1, 10]. When the phosphors were excited with UV radiation of 266 nm wavelength (4f-5d transition), the Tb3+ ion (4f8) would be raised to the higher 4f75d1 level and would feed afterward to the 5D3 or 5D4 excited states [12].Fig. 8


Green-Emitting Gd 3 Ga 5 O 12 : Tb 3+ Nanoparticles Phosphor: Synthesis, Structure, and Luminescence
Photoluminescence emission spectra of Gd3Ga5O12: 1 mol % Tb3+ nano- (a) and microceramics (b) at 266-nm excitation obtained at room temperature
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5383918&req=5

Fig8: Photoluminescence emission spectra of Gd3Ga5O12: 1 mol % Tb3+ nano- (a) and microceramics (b) at 266-nm excitation obtained at room temperature
Mentions: Photoluminescence emission spectra of Gd3Ga5O12: 1 mol % Tb3+ nano- and microceramic samples obtained at room temperature are shown in Fig. 8. A number of sharp intense lines were found in 350–650-nm spectral regions. These lines correspond to 5D3 (5D4) → 7Fj transitions in Tb3+ ions. Sharp weak lines with a maximum at 384, 420, and 440 correspond to 5D3 → 7F6, 5D3 → 7F5, and 5D3 → 7F4 transitions, respectively [1, 9, 10]. It should be noted that samples activated with 1 mol % Tb3+ ions reveal relatively high emission in a green spectral region. Luminescence lines in the spectral range of 480–650 nm with maxima at 491 nm (5D4 → 7F6), 546 nm (5D4 → 7F5), 597 nm (5D4 → 7F4), and 633 nm (5D4 → 7F3) are observed at longer wavelengths. Emission lines of 5D3 and 5D4 levels are associated with weak electron-vibrational transitions in Tb3+ ions [1, 10]. When the phosphors were excited with UV radiation of 266 nm wavelength (4f-5d transition), the Tb3+ ion (4f8) would be raised to the higher 4f75d1 level and would feed afterward to the 5D3 or 5D4 excited states [12].Fig. 8

View Article: PubMed Central - PubMed

ABSTRACT

Nano- and microceramics of Gd3Ga5O12 garnet doped with 1 mol % Tb3+ ions were synthesized via co-precipitation and high-temperature solid-state reaction methods. X-ray diffraction measurements confirmed the formation of the garnet structure with Ia3d space group in all investigated samples. Atomic force microscopy surface images and grain-size distribution diagrams of Gd3Ga5O12: 1 mol % Tb3+ nanoceramics with 300 and 400 g/mol of polyethylene glycol (PEG) were obtained. The relationship between the content of polyethylene glycol and the particle size of Gd3Ga5O12: Tb3+ phosphors was revealed. An intense broad band (λm = 266 nm) related to spin-allowed 4f8-4f75d1 transitions of Tb3+ ions was found in photoluminescence excitation spectra of Gd3Ga5O12: Tb3+ nanocrystalline ceramics with PEG-300 and PEG-400 at 300 K. The broad excitation band caused by spin-forbidden (λm = 295 nm) 4f-5d transitions in Tb3+ ions was additionally observed in the photoluminescence excitation spectra of Gd3Ga5O12: Tb3+ microceramics. Emission of Tb3+ ions under X-ray and UV excitations is presented by two groups of sharp lines which correspond to 5D3 and 5D4 → 7Fj transitions of Tb3+ ions with the most intense line at 546 nm (5D4 → 7F5). It was established that the increasing of PEG content leads to the decreasing of the X-ray and photoluminescence emission intensities.

No MeSH data available.