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Anomalous Temperature-Dependent Upconversion Luminescence of α-NaYF₄:Yb³⁺/Er³⁺ Nanocrystals Synthesized by a Microwave-Assisted Hydrothermal Method

Lili Tong, Xiangping Li, Ruinian Hua, Tianxiang Peng, Yizhuo Wang, Xizhen Zhang, Baojiu Chen

J Nanosci Nanotechnol. 2016 Jan;16(1):816-21.

PMID: 27398529

Abstract:

Yb³⁺/Er³⁺co-doped cubic-(α-) phase NaYF₄ nanocrystals were prepared through a microwave- assisted hydrothermal method. Temperature-dependent upconversion luminescence (UCL) and sensing properties were systematically studied. It is interesting that anomalous temperature- dependent UCL behavior is observed. With increasing temperature (303-573 K), the UCL intensity of Er³⁺ does not quench monotonously but reaches a minimum around 483 K and then increases. However, it was found that the UCL spectra change in a different way with decreasing temperature (573-303 K) from the one measured with increasing temperature. The fluorescence intensity ratio of ²H₁₁/₂ --> ⁴I₁₅/₂ to ⁴S₃/₂ --> ⁴I₁₅/₂ at any measured temperature point remains almost constant in all measurement processes, indicating the consistency of temperature in each spectrum measurement at all temperature points regardless of the heating or the cooling process in our experiments. The results demonstrate that NaYF₄:Yb³⁺/Er³⁺ UC nanocrystal has good sensing stability and may have potential application in the nanoscale thermal sensor.

Chemicals Related in the Paper:

Catalog Number Product Name Structure CAS Number Price
LS71332 Sodium yttrium fluoride, ytterbium and erbium doped Sodium yttrium fluoride, ytterbium and erbium doped Price
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