SuperESCA

Welcome to the Fast XPS beamline!

High resolution core-level photoemission spectroscopy (HR-XPS) allows in depth investigations on the electronic and structural properties of a variety of samples that ranges between single crystals, thin films as well as new nanostructured materials.
SuperESCA (the first beamline operating at Elettra since 1994) brings the possibilities of this technique even further: by combining high resolution capabilities with the high flux of linearly polarised photons in the 90 to 1500 eV range, in the beamline end-station it is possible to obtain high resolution spectra also for low-density systems (such as thin films or supported nanoparticles) and follow in real-time their evolution, e.g. during functionalization processes or surface reactions.

SuperESCA Highlights | Publications

Nitroxides adsorption on carbon nanotubes

XPS and XAS experiments, combined with DFT calculations, revealed that the reactivity of single-walled CNTs towards NO_x depends on their metallicity. Ultrapure metallic CNTs are twice more prone to NO₂ physisorption than their semiconducting counterparts, while the latter induce more dissociation on the adsorbed NO₂.

G. Ruiz-Soria et al., ACS Nano 8, 1375 (2014).

Read More

Ultrafast charge transfer to graphene monolayers

The charge transfer (CT) rates of a localized excited electron to graphene monolayers with variable substrate coupling were investigated by the core hole clock (CHC) method with adsorbed argon. CT time (τ_CT) to Gr depends strongly on Gr-substrate coupling and varies from ~16 fs, for decoupled Gr, to ~2.5 ns for strong coupling.

S. Lizzit et al., ACS Nano 7, 4359 (2013).

Read More

Patterning graphene with hydrogen clusters

Combined fast XPS and DFT calculations revealed the presence of two types of hydrogen adsorbate structures at the graphene/Ir(111) interface: graphane-like islands, giving rise to a periodic pattern, and dimers, which tend to destroy the periodicity. Distinctive growth rates and stability of the two types of structures allow obtaining well-defined patterns of clusters.

R. Balog et al., ACS Nano 7, 3823 (2013).

Read More

Oxygen intercaltion below epitaxial graphene

Oxygen intercalation below an extended layer of epitaxial graphene on Ir(111) is demonstrated using  real-time High-Resolution Photoemission Spectroscopy (HR-XPS). The resulting “lifted” graphene is decoupled from the Ir substrate and slightly p-doped as indicated by Angular Resolved Photoemission Spectroscopy (ARPES).  
R. Larciprete et al., ACS Nano 6, 9551 (2012).

Read More

Tailoring bimetallic alloy surface properties

Complex self-diffusion mechanisms determining key properties of binary alloys can be mostly defined by kinetic rather than energetic effects. In the Ni−Cu system, nanoscale control of these processes close to the surface yields tuning of the material functionality.


M. Rizzi et al., J. Am. Chem. Soc. 134, 16827 (2012).

Read More

Transfer-Free Electrical Insulation of Epitaxial Graphene

Stepwise intercalation of silicon and oxygen, allows the synthesis of a SiO₂ film below a graphene layer epitaxially grown on Ru(0001). We used photoemission spectroscopy to follow the reaction steps, which lead to a graphene layer electrically insulated from the substrate, as demonstrated by surface resistance data.

 
S. Lizzit et al., Nano Lett. 12, 4503 (2012).

Read More

Rh nanoclusters on graphene template

Graphene-supported Rh nanocluster assemblies and their geometry dependent electronic structure have been studied  by combining high-energy resolution core level photoelectron spectroscopy, scanning tunneling microscopy, and density functional theory.





A.. Cavallin et al., ACSNano 6, 3034 (2012).

Read More

H-bond mediated dissociation of ammonia on Si(001)

By combining DFT calculation and fast XPS measurements we demonstrate that the low temperature dissociation of NH₃ molecules chemisorbed on Si(001)-2x1 is driven by the continuous flux of ammonia molecules from the gas phase.



M. Satta et al., Phys. Rev. Lett. 109, 036102 (2012).

Read More

01234567

Proposal Submission

We invite users and collabrators to discuss their proposals with the beamline local contacts well in advance before the submission deadline. This is crucial for a careful assesment of the experiment feasibility and may lead to improvements in the proposed experimental plan. Our website provides a wealth of informaiton on experiment feasibilty and proposal submission. For more info, please vist the user info section.

Call for proposals

The deadline for proposal submission for beamtime allocation from January 1st to June 30th, 2015 will be September 15th, 2014 at 24:00 (MET).