New Materials for Nanothermometry

Starting date
February 1, 2017
Duration (months)
Managers or local contacts
Speghini Adolfo

The proposed project focuses on the study of new nanostructured materials and their possible use as optical
nanothermometers, as well as on physico-chemical and mechanistic aspects that regulate the transitions
ATTENZIONE: Il presente modulo deve essere caricato in formato .PDF attraverso la procedura on line.
inherent to the upconversion (UC) and dowhshifting (DS) processes and SERS diffusion in “ad-hoc”
functionalized metal nanoparticles (NPs).
The project articulates in two main lines:
1) development of nanostructures activated with suitable trivalent lanthanide (Ln3+) ions, luminescent in the
ultraviolet (UV), visible (VIS) and near infrared (NIR) regions, acting as optical nanothermometers. The focus
will be on nanoparticles (NPs) that can be excited in the NIR and emit in the UV and VIS (at higher energies than
the exciting radiation, due to upconversion processes, UC) or at lower energies (downshifting, DS) in the 900-
1600 nm NIR spectral range. In order to maximize the emission efficiency, a core@shell strategy will be
adopted fir the NPs, to minimize the multiphonon decay due to interactions between Ln3+ ions and the solvent
as well as to promote energy transfer processes between Ln3+ions.
2) study of the behavior of the Stokes and anti-Stokes Raman components intensified by interaction with the
metal plasmon of some simple organic molecules as a function of the temperature. In order to obtain and
exploit the SERS effect, the chosen organic molecules will be anchored to the metal surface of the NPs (gold or
silver). From the Raman experiments, understanding of the physico-chemical mechanisms underlying SERS
intensification will be obtained.
The sensitivity and thermal resolution of these thermometers will be measured and analyzed in the 20°C – 60°C
temperature range by the ratio of integrated areas related to different emissions. The efficiency of the
temperature sensor based on the SERS effect will be evaluated with reference to particular molecular
vibrational modes

Project participants

Adolfo Speghini
Associate Professor


Research facilities