Abstract
The spectroscopic properties of a Dy3+-doped aluminophosphate glass containing silver and tin were reported. Different oxidation and aggregation states of silver
were obtained by varying silver concentration and glass thermal history. The addition of silver and tin at the lowest concentration
studied results in Dy3+ ions emission under nonresonant UV excitation in connection with the appearance of an excitation band around 270 nm, which
is associated to isolated Ag+ ions and twofold-coordinated Sn centers. The increase in silver and tin concentration leads to a broadening of aforementioned
band and to the presence of charged silver dimers as evidenced by the appearance of an excitation band around 330 nm. The
data indicated that light absorption might take place at ionic silver species and twofold-coordinated Sn centers, followed
by energy transfer to Dy3+ ions. After heat treatment, ionic silver species were reduced to atomic Ag by tin with the subsequent formation of Ag nanoparticles
(NPs) inside the dielectric host. A quenching effect in Dy3+ ions luminescence was shown with the presence of the Ag NPs, most notably for excitation of 6H15/2 → 4F9/2, 4I15/2, 4G11/2 transitions, which were in resonance with the dipole absorption mode of the particles. The silver NPs were believed to provide
radiationless pathways for excitation energy loss in Dy3+ ions.
were obtained by varying silver concentration and glass thermal history. The addition of silver and tin at the lowest concentration
studied results in Dy3+ ions emission under nonresonant UV excitation in connection with the appearance of an excitation band around 270 nm, which
is associated to isolated Ag+ ions and twofold-coordinated Sn centers. The increase in silver and tin concentration leads to a broadening of aforementioned
band and to the presence of charged silver dimers as evidenced by the appearance of an excitation band around 330 nm. The
data indicated that light absorption might take place at ionic silver species and twofold-coordinated Sn centers, followed
by energy transfer to Dy3+ ions. After heat treatment, ionic silver species were reduced to atomic Ag by tin with the subsequent formation of Ag nanoparticles
(NPs) inside the dielectric host. A quenching effect in Dy3+ ions luminescence was shown with the presence of the Ag NPs, most notably for excitation of 6H15/2 → 4F9/2, 4I15/2, 4G11/2 transitions, which were in resonance with the dipole absorption mode of the particles. The silver NPs were believed to provide
radiationless pathways for excitation energy loss in Dy3+ ions.
- Content Type Journal Article
- DOI 10.1007/s10853-010-4297-7
- Authors
- J. A. Jiménez, University of Puerto Rico Department of Chemistry P.O. Box 9019 Mayagüez PR 00681-9019 USA
- S. Lysenko, University of Puerto Rico Department of Physics P.O. Box 9016 Mayagüez PR 00681-9016 USA
- H. Liu, University of Puerto Rico Department of Physics P.O. Box 9016 Mayagüez PR 00681-9016 USA
- Journal Journal of Materials Science
- Online ISSN 1573-4803
- Print ISSN 0022-2461
No comments:
Post a Comment