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Gd3+-Doping Effect on Upconversion Emission of NaYF4: Yb3+, Er3+/Tm3+ Microparticles.

ABSTRACT: ?-NaYF4 microcrystals co-doped with Yb3+, Er3+/Tm3+, and Gd3+ ions were synthesized via a hydrothermal method using rare-earth chlorides as the precursors. The SEM and XRD data show that the doped ?-NaYF4 form uniform hexagonal prisms with an approximate size of 600-800 nm. The partial substitution of Y by Gd results in size reduction of microcrystals. Upconversion luminescence spectra of microcrystals upon 980 nm excitation contain characteristic intra-configurational ff bands of Er3+/Tm3+ ions. An addition of Gd3+ ions leads to a significant enhancement of upconversion luminescence intensity with maxima at 5 mol % of dopant.

SUBMITTER: Vidyakina AA

PROVIDER: S-EPMC7435447 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Gd3+-Doping Effect on Upconversion Emission of NaYF4: Yb3+, Er3+/Tm3+ Microparticles.

Vidyakina Aleksandra A AA Kolesnikov Ilya E IE Bogachev Nikita A NA Skripkin Mikhail Y MY Tumkin Ilya I II Lähderanta Erkki E Mereshchenko Andrey S AS

Materials (Basel, Switzerland) 20200731 15

β-NaYF4 microcrystals co-doped with Yb3+, Er3+/Tm3+, and Gd3+ ions were synthesized via a hydrothermal method using rare-earth chlorides as the precursors. The SEM and XRD data show that the doped β-NaYF4 form uniform hexagonal prisms with an approximate size of 600-800 nm. The partial substitution of Y by Gd results in size reduction of microcrystals. Upconversion luminescence spectra of microcrystals upon 980 nm excitatio ...[more]

PMID: 32751966

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