Upconversion in NaYF4: Yb, Er nanoparticles amplified by metal nanostructures

Wei Deng, L. Sudheendra, Jiangbo Zhao, Junxiang Fu, Dayong Jin, Ian M. Kennedy, Ewa M. Goldys

Research output: Contribution to journalArticlepeer-review

69 Scopus citations

Abstract

Upconversion (UC) fluorescence in NaYF4:Yb, Er nanoparticles amplified by metal nanostructures was compared in two nanostructure geometries: gold nanoshells surrounding nanoparticles and silver nanostructures adjacent to the nanoparticles, both placed on a dielectric silica surface. Enhanced UC luminescence signals and modified lifetimes induced by these two metals were observed in our study. The UC luminescence intensities of green and red emissions were enhanced by Ag nanostructures by a factor of approximately 4.4 and 3.5, respectively. The corresponding UC lifetimes were reduced ∼ 1.7-fold and ∼ 2.4-fold. In NaYF4:Yb, Er nanoparticles encapsulated in gold nanoshells, higher luminescence enhancement factors were obtained (∼9.1-fold for the green emission and ∼ 6.7-fold for the red emission). However, the Au shell coating extended the red emission by a factor of 1.5 and did not obviously change the lifetime of green emission. The responsible mechanisms such as plasmonic enhancement and surface effects are discussed.

Original languageEnglish (US)
Article number325604
JournalNanotechnology
Volume22
Issue number32
DOIs
StatePublished - Aug 12 2011

ASJC Scopus subject areas

  • Bioengineering
  • Chemistry(all)
  • Electrical and Electronic Engineering
  • Mechanical Engineering
  • Mechanics of Materials
  • Materials Science(all)

Fingerprint Dive into the research topics of 'Upconversion in NaYF<sub>4</sub>: Yb, Er nanoparticles amplified by metal nanostructures'. Together they form a unique fingerprint.

Cite this