Correlation between preparation conditions and the photoluminescence properties of Sn²⁺ centers in ZnO–P₂O₅ glasses

Abstract

Sn2+ centers exhibiting high quantum efficiency were observed in zinc phosphate glasses prepared under inert conditions.

Correlations between Glass Structure and Emission Properties of Sn-Doped Zinc Phosphate Glasses Prepared with Different Cooling Rates

“…Furthermore, the decay constants accord with the Sn 2+ centers. (7)(8)(9)11,13,29) Considering the PL spectra and decay curves, the radiative process is almost single, although there exist two different excitation states of Sn…”

“…(7)(8)(9)(10)(11)(12) Sn 2+ centers belong to the group of ns 2 -type (n ≥ 4) emission centers, (13) whose electrons in the outermost shell contribute to the emission process. This means that the emission properties are strongly affected by the coordination states of ns 2 -type emission centers.…”

Photo- and Radioluminescence of Sn2+ Centers in Alkaline Earth Oxide-Substituted Zinc Phosphate Glass

“…(14) The chemical composition of the glasses was fixed as 1SnO-xRO-(60-x)ZnO-40P 2 O 5 (x = 0-20) (mol%), in which ZnO is substituted by an alkaline earth oxide. Batches consisting of ZnO, (NH 4 ) 2 HPO 4 , and substitutes such as MgO, CaCO 3 , SrCO 3 , and BaCO 3 were first mixed and calcined at 1073 K for 3 h. After cooling, SnO was added to the heat-treated solids and the mixture was melted at 1373 K for 30 min in Ar atmosphere.…”

“…Recently, our group has focused on a RE-free amorphous phosphor using ns 2 -type cations. (11)(12)(13)(14)(15)(16)(17)(18)(19) Because an ns 2 emission center possesses an electron in the outermost shell in both the ground state (ns 2 ) and the excited state (ns 1 np 1 ), these types of emission centers are strongly affected by the coordination state. Although we have reported scintillation properties of the ns 2 -center-containing oxide glasses, (18,19) their efficiency is insufficient for industrial application.…”

“…However, this suggestion should be reevaluated, because the preparation was performed in air, in which Sn 2+ can be oxidized easily into Sn 4+ . (14) In addition, there was no information about the glass network that may affect the local coordination state of the Sn 2+ center. Furthermore, examination of PL properties only is insufficient, because both PL and RL measurements may complement each other.…”