Non-Linear Optical Properties of Er3+-Yb3+-Doped NaGdF4 Nanostructured Glass-Ceramics.
José J VelázquezGiulio GorniRolindes BaldaJoaquin FernándezLaura PascualAlicia DuránMaria J PascualPublished in: Nanomaterials (Basel, Switzerland) (2020)
Transparent oxyfluoride glass-ceramics containing NaGdF4 nanocrystals were prepared by melt-quenching and doped with Er3+ (0.5 mol%) and different amounts of Yb3+ (0-2 mol%). The selected dopant concentration the crystallization thermal treatments were chosen to obtain the most efficient visible up-conversion emissions, together with near infrared emissions. The crystal size increased with dopant content and treatment time. NaGdF4 NCs with a size ranging 9-30 nm were obtained after heat treatments at Tg + 20-80 °C as confirmed by X-ray diffraction and high-resolution transmission electron microscopy. Energy dispersive X-ray analysis shows the incorporation of rare earth ions into the NaGdF4 nanocrystals. Near-infrared emission spectra, together with the up-conversion emissions were measured. The optical characterization of the glass-ceramics clearly shows that Er3+ and Yb3+ ions are incorporated in the crystalline phase. Moreover, visible up-conversion emissions could be tuned by controlling the nanocrystals size through appropriated heat treatment, making possible a correlation between structural and optical properties.
Keyphrases
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- room temperature
- estrogen receptor
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- mass spectrometry
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- magnetic resonance
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- metal organic framework
- gas chromatography mass spectrometry
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- density functional theory
- molecular dynamics
- crystal structure