Jump to main content
Jump to site search
PLANNED MAINTENANCE Close the message box

Scheduled maintenance upgrade on Thursday 4th of May 2017 from 8.00am to 9.00am (BST).

During this time our websites will be offline temporarily. If you have any questions please use the feedback button on this page. We apologise for any inconvenience this might cause and thank you for your patience.

Cooperative and non-cooperative sensitization upconversion in lanthanide-doped LiYbF4 nanoparticles


Lanthanide (Ln3+)-doped upconversion nanoparticles (UCNPs) have attracted tremendous interest for their potential bioapplications. However, the intrinsic photophysics responsible for upconversion (UC) especially the cooperative sensitization UC (CSU) in colloidal Ln3+-doped UCNPs remains untouched so far. Herein, we report a unique strategy for the synthesis of high-quality LiYbF4:Ln3+ core-only and core/shell UCNPs with tunable particle size and shell thickness. Energy transfer UC from Er3+, Ho3+ and Tm3+ and CSU from Tb3+ were comprehensively surveyed under 980-nm excitation. Through surface passivation, we achieved efficient non-cooperative sensitization UC with absolute UC quantum yield (QY) of 3.36%, 0.69% and 0.81% for Er3+, Ho3+ and Tm3+, respectively. Particularly, we for the first time quantitatively determined the CSU efficiency for Tb3+ with an absolute QY of 0.0085% under excitation at a power density of 70 W·cm-2. By means of temperature-dependent steady-state and transient UC spectroscopy, we unraveled the dominant mechanisms of phonon-assisted cooperative energy transfer (T > 100 K) and sequential dimer ground-state absorption/excited-state absorption (T < 100 K) for the CSU process in LiYbF4:Tb3+ UCNPs.

Back to tab navigation
Please wait while Download options loads

Supplementary files

Publication details

The article was accepted on 06 Apr 2017 and first published on 11 Apr 2017

Article type: Paper
DOI: 10.1039/C7NR02124K
Citation: Nanoscale, 2017, Accepted Manuscript
  •   Request permissions

    Cooperative and non-cooperative sensitization upconversion in lanthanide-doped LiYbF4 nanoparticles

    Q. Zou, P. Huang, W. Zheng, W. You, R. Li, D. Tu, J. Xu and X. Chen, Nanoscale, 2017, Accepted Manuscript , DOI: 10.1039/C7NR02124K

Search articles by author