The understanding of nanoparticle properties when they exist as free isolated objects is a crucial point for the assessment of a bottom-up approach to nanostructured materials growth like our Supersonic Cluster Beam Deposition technique. Our group has a long-standing tradition in the development of gas-phase- clusters and nanoparticles characterization methods and in the original design and fabrication of dedicated instruments and apparatus. Aerodynamic-separation techniques are used for nano-object manipulation in terms of classification and concentration of nanoparticles into high-intensity and low-divergence molecular beams under High- or Ultra High- Vacuum conditions; these beams have been demonstrated to be suitable means for the application of advanced characterization methods like core-level photoemission spectroscopy and related techniques based on the coincidence detection of charged-products from highly diluted samples.
Related research lines:
Free clusters and nanoparticles core-level spectroscopy via multi-coincidence electrons and ions detection.
Our aim is to develop new technology to advance beyond the
measurement of mass and number concentration of airborne nanoparticles
or the determination of their elemental composition and chemical
structure, towards real-time access to information on the full-range of
their physical chemistry properties (on the time scale of their
agglomerations and transformations).
Advanced light sources in the
VUV and XUV are promising facilities to achieve these results owing to
the chemical sensitivity and to the local character of the core-level
spectroscopy tools to which they provide access. Within the frame of a
Long Term proposal accepted by synchrotron radiation facility Elettra,
we have developed a UHV apparatus equipped with double-Velocity Map
Imaging (VMI) spectrometer for imaging coincidence detection of
electrons and ions on a multi-hit detector (MCP with triple- delay-line
anode). The apparatus, after being commissioned on November 2017 with
XAS and PES measurements on free Ti and V clusters, is fully operational
and open to external users proposals.
This Project is pursued in
collaboration with the SQS instrument research team at XFEL and with the
GasPhase@Elettra and LDM@FERMI joint research group.
Referent: Paolo Piseri
Participants: Paolo Piseri, Claudio Piazzoni