Observation of Intra‐ and Inter‐Configurational Luminescence of Pr³⁺‐Doped Strontium Phosphate Glasses

Abstract

Emissions due to inter‐configurational 4f15d1‐4f2 electronic transitions of Pr3+ ions are scarcely observed in phosphate glasses. In this work, the intense UV emissions (at 311 and 327 nm) owing to the inter‐configurational f‐d transitions of Pr3+ have been reported in Pr3+‐doped strontium phosphate glasses. Characteristic blue (481, 488 nm), green (522 nm), orange (597, 610 nm), and red (638 nm) emissions are also observed due to the intra‐configurational f‐f transitions. Possible mechanisms controlling the intra‐ and inter‐configurational transitions of Pr3+ ions are discussed.

Effect of BaF2 Content on Luminescence of Rare‐Earth Ions in Borate and Germanate Glasses

“…Taking into account the relative integrated intensity of these two bands connected with 3 P 0 → 3 H 4 and 3 P 0 → 3 F 2 transition, we can conclude, that the luminescence behavior of Pr 3+ ions in oxyfluoride germanate glasses firmly depend on BaF 2 concentration. Similar spectra were obtained for Pr 3+ ions in oxyfluoride silicate glasses and glass‐ceramics, strontium phosphate glasses, lanthanum fluorozirconate glass, as well as in other glass systems already examined …”

“…Because the interaction of Pr 3+ ions with lattice phonons is responsible for the nonradiative relaxation, an effective emission originating from 1 D 2 level can be observed only in hosts possessing high phonon energies that are comparable to the energy separation between 3 P 0 → 1 D 2 levels. As was previously shown, the nonradiative populating of 1 D 2 level from 3 P 0 level is inefficient in aluminates of low phonon energies, while efficient emission from 1 D 2 is observed in the SrAl 2 O 4 phosphors and in phosphate glasses, which possess higher phonon energies.…”

Broad blue-green-red emissions of SnO2/Pr3+ co-doped phosphate glasses

“…The possible ET processes from SnO 2 to Pr 3+ are illustrated in Fig. 3 [9][10][11]. The three valleys can be explained by the following energy cross-relaxation between SnO 2 and Pr 3+ :…”

“…Actually, this band can be decomposed to two bands at 311 and 327 nm. They are attributed to the transitions from the Pr 3+ 4f 1 5d 1 state to 3 H 5 and 3 H 6 states respectively [11]. A clear red emission band arises in the co-doped sample (SP05), it consists of two bands at 597 nm and 610 nm corresponding to the Pr 3+ 1 D 2 -3 H j (j = 4,5) transitions [11,12].…”

“…The 290, 442, 468, 480 and 590 nm absorption bands characteristic of Pr 3+ are observed in the Pr 3+ doped samples (P05, SP05). They are assigned to the 4f-4f transitions of 3 H 4 →4f 1 5d 1 (290 nm), 3 H 4 → 3 P j (j=2,1,0), 3 H 4 → 1 D 2 , respectively [11].…”