Due to the upcoming ELETTRA 2.0 upgrade, this technique will be provided at TUG@Trieste only at laboratories until further notice.
Small Angle X-ray Scattering is a non-destructive and highly versatile standard method to study at the nanoscale the structure of any type of material ranging from innovative nanostructured materials to biological macromolecules. With this technique, the in- homogeneities of the electron density in the samples are characterized, as a function of the scattering angle.
The investigated sample is irradiated with a monochromatic radiation, and scattered X-rays are typically collected in an angular range of 0 – 10° by a suitable detector (ie. CCD or imaging plate) and up to 60° (by using an imaging plate for the systems coupling SAXS and Wide Angle X-Ray Scattering, WAXS). By means of appropriate model fittings and reconstructions, SAXS data deliver information on averaged particle sizes, shapes, distributions and materials' porosity.
SAXS allows structural studies in a dimension range typically between 1 and 100 nm; the dimension limits depend on the selected instrument. Samples can be probed in solution, solid, at the interface or in the gas phase; with specially designed sample holders, they can be measured under various conditions, like at different temperature, humidity, high pressure and under mechanical stress/strain conditions. Moreover, SAXS can be used for time-resolved studies on fast structural transitions during chemical reactions or self-assembly process.
Grazing-incidence (GISAXS) measurements can be performed to study self-assembly processes on surfaces, as well as to perform structural characterisations of thin films.
At wider scattering angle (Wide Angle X-ray Scattering, WAXS), intramolecular dimensions, as well as the degree of crystallinity of the samples, can be probed.
- Flow through cell for sample recirculation, eventually coupled with a thermostatable capillary holder (temperature range -30 – 150°C and 70 – 300°C).
- Craddle for Grazing incidence SWAXS: Sample movement precision: rotation: 0.001 deg; translation : 5µm.
- Domed hot stage for GISAXS: temperature range, 25 – 1100°C.
- Stop flow: i) 4- syringe cell with 3 mixer modules for inorganic samples, and ii) 2-syringes, dedicated for biological samples.
- High pressure cell system for transmission and grazing incidence experiments. Pressure range: 1-2500 Bar, Temperature range 0 – 80°C.
- In-line Differential Scanning Calorimeter (DSC) for simultaneous time-resolved synchrotron X-ray diffraction as a function of the temperature and high sensitivity DSC from the same sample. Heating rate: 0.1 to 10 °C/min, with a 0.01 °C temperature resolution in the range -30/+130 °C.
- Relative Humidity controlled cell for GISAXS.
- Autosampler for automated processing of up to 480 liquid samples: required sample volume, 100 µl (approximately 20 µl/single measurement); cycle time (excluding measuring time): 35-50 s.
- SEC-SAXS: Size Exclusion Chromatography system equipped with UV-Vis spectrometer, a Multi angle Light Scattering detector (MALS) and a Refractive Index refractometer (RI) installed in-line with the SAXS flowthrough cell.
In SEM a beam is scanned over a sample surface while a signal from secondary or back-scattered electrons is recorded. SEM is used to image an area of the sample with nanometric resolution, and also to measure its composition, crystallographic phase distribution and local texture.
In TEM/Scanning TEM (STEM) high energy electrons incident on ultra-thin samples, allow imaging, diffraction, electron energy loss spectroscopy and chemical analysis of solid materials with a spatial resolution on the order of 1-2 Å. Samples must have a thickness of a few tens of nanometres and are prepared in sample preparation laboratory.
XPS is a surface spectroscopic technique for quantitative measurements of the elemental composition or stoichiometry and the chemical state of the present elements, like their oxidation state and chemical bonds. XPS is highly surface sensitive, giving chemical and binding energy information from the a narrow region close to the surface.
The pump-probe spectroscopy infrastructure provides in-situ probes of the excited state of the matter, i.e. in the time/frequency domain at the fs-ps scales.
VUV/UV/Vis/NIR spectroscopy is the measurement of the attenuation of a beam of light after it passes through a sample or after reflection from a sample surface. It is useful to characterize absorption, transmission, and reflectivity of a variety of technologically important materials, such as gases, film, pigments, coatings, windows, and filters.
