5 years ago

Improving 800 nm Triggered Upconversion Emission for Lanthanide-Doped CaF2 Nanoparticles through Sodium Ion Doping

Improving 800 nm Triggered Upconversion Emission for Lanthanide-Doped CaF2 Nanoparticles through Sodium Ion Doping
Huimei He, Tianyou Zhai, Bing Xu, Shengye Jin, Zhanjun Gu, Ying Ma
Lanthanide ions (Ln3+)-doped CaF2 luminescent nanoparticles exhibit unique optical properties and represent promising candidates for bioapplications; however, their inherent weak luminescence intensity greatly limits their application, especially for Nd3+-sensitized ones. We have doped Ln3+ ions along with Na+ ion into CaF2 lattice to maintain charge neutrality and investigated the influence of Na+ ion on the 800 nm triggered upconversion process. As compared with Na+-free (shell layer) nanoparticles, the crystallinity of Na+-ion-codoped ones has been improved greatly, and the average lifetimes of the excited Nd3+, Yb3+, and Er3+ states have been prolonged after Na+ ion codoping in the sensitizing shell. Thus the energy-transfer efficiency from sensitizers (Nd3+) to activators (Er3+) has been increased by 67%. As a result, the upconversion luminescence intensity of the nanoparticles with suitable Na+ doping reaches 67 times higher than Na+-free nanoparticles upon 800 nm irradiation, although fewer Ln3+ ions were doped into CaF2 in this case. The as-synthesized CaF2:Yb/Er@CaF2:Nd/Yb core–shell structured (CS) UCNPs may be good candidates as excellent imaging nanoprobes because of their good biocompatibility.

Publisher URL: http://dx.doi.org/10.1021/acs.jpcc.7b05639

DOI: 10.1021/acs.jpcc.7b05639

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.