Influence of the synthesis parameters on the properties of NaYF4:Yb3+,Tm3+ nanoparticles

• Main Authors: Olivija Plohl, Boris Majaron, Maja Ponikvar-Svet, Darko Makovec, Darja Lisjak
• Format: Article
• Language: English
• Published: Slovenian Chemical Society 2015-07-01
• Series: Acta Chimica Slovenica
• Subjects: nanoparticles; dissolution; fluorescence; up-conversion
• Online Access: https://journals.matheo.si/index.php/ACSi/article/view/1508

Fluorescent nanoparticles, especially fluorides, have received a great deal of interest due to their optical properties, making them suitable for applications in bio-imaging. For this reason they need to exhibit a superior chemical stability in aqueous media. We have studied the influence of the synthesis parameters on the chemical stability of NaYF4 nanoparticles co-doped with Yb3+ and Tm3+. These nanoparticles have different crystal structures, and were synthesized hydrothermally or with thermal decomposition. The samples were characterized with X-ray diffraction and transmission electron microscopy. The up-conversion fluorescence of nanoparticles dispersed in water was measured at 400–900 nm. The partial dissolution of the fluorine in water was detected with an ion-selective electrode for all the samples. The dissolution of the other constituent ions was analysed with an optical emission spectrometer using inductively coupled plasma. The nanoparticles with a hexagonal crystal structure and sizes of around 20 nm that were synthesized with thermal decomposition showed a superior chemical stability in water together with a superior up-conversion fluorescence yield.