Self-Sufficient and Highly Efficient Gold Sandwich Upconversion Nanocomposite Lasers for Stretchable and Bio-applications.
Monika KatariaKanchan YadavAmit NainHung-I LinHan-Wen HuChristy Roshini Paul InbarajTing-Jia ChangYu-Ming LiaoHao-Yu ChengKung-Hsuan LinHuan-Tsung ChangFan Gang TsengWei-Hua WangYang-Fang ChenPublished in: ACS applied materials & interfaces (2020)
Multifunctional lanthanide-doped upconversion nanoparticles (UCNPs) have spread their wings in the fields of flexible optoelectronics and biomedical applications. One of the ongoing challenges lies in achieving UCNP-based nanocomposites, which enable a continuous-wave (CW) laser action at ultralow thresholds. Here, gold sandwich UCNP nanocomposites [gold (Au1)-UCNP-gold (Au2)] capable of exhibiting lasing at ultralow thresholds under CW excitation are demonstrated. The metastable energy-level characteristics of lanthanides are advantageous for creating population inversion. In particular, localized surface plasmon resonance-based electromagnetic hotspots in the nanocomposites and the huge enhancement of scattering coefficient for the formation of coherent closed loops due to multiple scattering facilitate the process of stimulated emissions as confirmed by theoretical simulations. The nanocomposites are subjected to stretchable systems for enhancing the lasing action (threshold ∼ 0.06 kW cm-2) via a light-trapping effect. The applications in bioimaging of HeLa cells and antibacterial activity (photothermal therapy) are demonstrated using the newly designed Au1-UCNP-Au2 nanocomposites.
Keyphrases
- reduced graphene oxide
- visible light
- highly efficient
- gold nanoparticles
- silver nanoparticles
- energy transfer
- quantum dots
- sensitive detection
- photodynamic therapy
- carbon nanotubes
- induced apoptosis
- cell cycle arrest
- molecular dynamics
- magnetic resonance imaging
- monte carlo
- oxidative stress
- cancer therapy
- mass spectrometry
- sewage sludge
- pi k akt