Time-resolved photoluminescence analysis of distribution and migration of terbium ions in zeolites X

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• 作者：Tiseanu ; Carmen ; Frunza ; Ligia ; Kumke ; Michael
• 关键词：71.55.Ht ; 39.90 ; 78.47 ; 83.80.P ; Lanthanides ; Time-resolved luminescence spectroscopy ; Zeolites
• 刊名：Physica B
• 出版年：2004
• 出版时间：October 30, 2004
• 年：2004
• 卷：352
• 期：1-4
• 页码：358-365
• 全文大小：253 K

文摘

The photoluminescence (PL) dynamics of terbium-exchanged zeolites X was investigated upon laser excitation at 355nm. The results evidenced the presence of at least two terbium main environments with PL lifetimes varying between 391–411 and 753–770μs. The two-site nature of terbium distribution in zeolites X permitted a quantitative analysis of the migration process of terbium ions inside the pores and cavities upon dehydration in air at 200°C. Besides the increase of the PL lifetimes with about 30 % and 80 % compared to those of the hydrated zeolite, a fraction of almost 30 % of terbium ions was estimated to migrate from the supercages to the neighboring sodalites or hexagonal prisms. Our results evidenced for the first time the capability of time-resolved luminescence spectroscopy in quantitatively tracking for the intrazeolitic migration of lanthanides.