Jump to main content
Jump to site search

Issue 6, 2017
Previous Article Next Article

Physiochemical properties of greatly enhanced photoluminescence of aqueous dispersible upconversion CaF2:Yb/Er nanoparticles

Author affiliations

Abstract

Crystal phase morphological structure and optical properties of the as-prepared upconversion CaF2:Yb/Er(core) and sequential coating of an inert crystalline material and silica layers surrounding the seed core-nanoparticles (NPs) were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), optical absorption, FTIR spectroscopy and upconversion photoluminescence spectroscopy. Owing to the unique properties of CaF2 host matrix, we realized their practical applications in biomedical science to improve the upconversion luminescence property and aqueous dispersibility. The surface coating on the seed core particles will significantly influence the structural, optical band gap energy and upconversion luminescence properties. These NPs were well-dispersed in aqueous and non-aqueous solvents to form clear colloidal solutions. The colloidal solutions of three samples show a characteristic optical absorption band in UV/Visible region. As a result, optical band gap gradually decreases after sequential growth of the inert shell and amorphous silica due to an increase in the crystalline size. Comparative upconversion luminescence analysis showed that after inert shell growth, the upconversion intensity was greatly improved, and such an improvement was found to arise from efficient suppression of surface-related deactivation from the core nanocrystals. Interestingly, growth of an inert (CaF2) shell over the seed core NPs shows intense upconversion emission lines under 980 nm NIR laser excitation, highlighting their promising applications, such as multi-analyte biolabels, staining, displays and other photonic based technological applications.

Graphical abstract: Physiochemical properties of greatly enhanced photoluminescence of aqueous dispersible upconversion CaF2:Yb/Er nanoparticles

Back to tab navigation

Publication details

The article was received on 13 Dec 2016, accepted on 16 Mar 2017 and first published on 20 Mar 2017


Article type: Paper
DOI: 10.1039/C6PP00448B
Citation: Photochem. Photobiol. Sci., 2017,16, 890-896
  •   Request permissions

    Physiochemical properties of greatly enhanced photoluminescence of aqueous dispersible upconversion CaF2:Yb/Er nanoparticles

    A. A. Ansari, R. Yadav and S. B. Rai, Photochem. Photobiol. Sci., 2017, 16, 890
    DOI: 10.1039/C6PP00448B

Search articles by author

Spotlight

Advertisements