Effect of Eu-doping on optical, structural and morphological properties of BaI2·nH2O powders

Influence of Golden Nanoparticles on the Incorporation of Eu2+ into BaI2 and Defect Concentration

“…The spectra are shown in Figure 4. The RL spectra are composed of the two signals: dominating band attributed to Eu 2+ in BaI2 and the weaker band within the ~1.8-2.7 eV r Eu 2+ in EuI2 based on previous work [19] (Figure 4). The spectral positi do not depend on the GNP content while their intensities are decreasi strongly with PL spectra measurements in Figure 2.…”

“…The main PL bands are narrow and almost symmetric with the maximum at about 3 eV (Figure 2a). They were related to the Eu 2+ 4f 6 5d 1 → 4f 7 transition in BaI2 [19], [39]. Another "tail"-like band in the 2.2-2.8 eV region can be visible for all the samples (Figure 2a).…”

“…The following materials of analytical grade were used in the sample synthesis: Ba(NO 3 ) 2 , NH 4 I, Eu(NO 3 ) 3 •6H 2 O, NH 4 HCO 3 , NaOH, Na 2 EDTA and HAuCl 4 . A two-stage process, described in more detail in [19,32], was used for BaI 2 :Eu powders synthesis. GNPs were added in the form of Au solution in the amount of 0, 0.01, 0.05 and 0.2 wt.% to the precursor BaCO 3 :Eu which was prepared during the first stage of synthesis.…”

“…Eu 2+ and Eu 3+ ions represent a suitable activator for BaI 2 while their effect on structural, morphological and optoelectronic properties have been previously subjected to research in [18,19].…”

Luminescent materials in the form of glass ceramic

“…Designations correspond to the table 1обусловлено люминесценцией Eu 2+ в EuI 2[14], кислородными центрами[15] или различными типами экситонных (экситонподобных) состояний[16]. Также не исключается совместное действие перечисленных механизмов[8]. Отсутствие полос у Eu 3+ при возбуждении с 395 нм указывает на тушение его люминесценции в исследуемых образцах.У стеклокерамики на основе BaI 2 : Eu 2+ на СЛ зарегистрированы полосы для ионов Eu 3+ и Eu 2+ (см.…”