Miao Liu
INRS EMT, Varennes, QC

Ph.D. student in energy and materials science (Prof. Liang’s group)

Title of the talk:

Near-infrared lifetime mapping of rare-earth doped nanoparticles using ultrahigh-speed line-scanning microscopy

Abstract: Luminescent nanomaterials—which can be excited and emit in the near-infrared (NIR) range—have attracted great attention in a plethora of applications, including nanomedicine, biosensing, bioimaging, solar cells, and photocatalysis. Especially in biomedical applications, NIR light mitigates the drawbacks associated with ultraviolet and/or visible light (e.g. photodamage, background autofluorescence, and limited penetration depth). At the forefront of NIR-excited nanomaterials are rare-earth doped nanoparticles (RENPs) that possess exceptional optical properties, such as programmable emission, long luminescence lifetime, and high photostability. However, the NIR lifetime property of RENPs and their potential application are rarely explored. One of the limitations is the instruments since the current techniques, such as time-correlated single-photon counting, have limited measurement efficiency. Here, we present the synthesis of various NIR-excited and NIR-emitting RENPs. Their lifetimes are characterized by using a newly developed ultrahigh-speed line-scanning microscopy. The potential use of NIR lifetimes in anticounterfeiting and nanothermometry will also be demonstrated.