White light emission from γ-irradiated Ag/Eu co-doped phosphate glass under NUV light excitation

Tunable white light emission from γ-irradiated Ag/Eu co-doped phosphate glass phosphor

“…In our previous work [22], we confirmed the absence of Eu 2+ and silver aggregates in glasses before γ-irradiation. The characteristic "U" spectra (at g~2.0, g~2.8, and g~6.0) of Eu 2+ in EPR spectra suggest the partial reduction of Eu 3+ after γ-irradiation [22][23][24]. The EPR signals of Ag 2+ (g ⊥~2 .05 and g∥~2.35), Ag 2 + (g~1.994), and Ag 3 2+ (g~1.980) were clearly observed in Fig.…”

“…The EPR signals of Ag 2+ (g ⊥~2 .05 and g∥~2.35), Ag 2 + (g~1.994), and Ag 3 2+ (g~1.980) were clearly observed in Fig. 1(a) [22,25]. Likewise, the absorption bands of Ag 2+ at 260 nm, Ag 2 + at 320 nm, Ag 0 at 345 nm, and Ag 3 2+ at 375 nm were observed in Fig.…”

“…These results indicate the appearance of silver aggregates after γ-irradiation. ) [22,24]. The irradiation induced electrons are invariable for the same glass host under irradiation with identical dose.…”

“…Phosphate glasses with compositions (mol%) of 65NaPO 3 -30Al(PO 3 ) 3 -5SiO 2 -xAgNO 3 -yEu 2 O 3 (x = 1.5, y = 0.2, 0.5, 0.8, 1.2, 1.5, and x = 1, 2, 3, 4, y = 0.8) were melted via the traditional melt quenching method using reagent grade NaPO 3 , Al(PO 3 ) 3 , SiO 2 , AgNO 3 , and Eu 2 O 3 as starting materials [22]. The stoichiometric chemicals were thoroughly mixed and melted in a covered alumina crucible at 1250 °C for 2 h. The melt was then cast into a preheated iron mold and annealed in a muffle furnace at 450 °C for 2 h. Samples with sizes of 25 × 10 × 2 mm 3 were cut and polished for optical measurements.…”

“…In our previous work, we presented a new single-phased γ-irradiated Ag/Eu co-doped phosphate glass phosphor based on near ultraviolet (NUV) LED chips, which offers an alternative for efficient white light emission [22]. The formation mechanism of silver aggregates (Ag 2 + and Ag 3…”