The XMI research group applies both laboratory and synchrotron radiation sources for spatially resolved, highly sensitive multi-elemental analysis on the micro/nanoscopic level of a variety of samples. Below, an overview is presented regarding the available laboratory instrumentation together with several key-papers:
A laboratory XRF microprobe is equipped with an air-cooled X-ray tube with a Rh anode, a polycapillary lens (X-ray Optical Systems, XOS, USA) for X-ray focusing and an 80 mm² energy dispersive Si(Li) detector cooled by liquid nitrogen. The EDAX EagleIII allows to investigate the major/minor elemental distribution with an X-ray beam size down to 20 µm under ambient or vacuum conditions. As the instrument can be operated under vacuum, the attenuation of low energy X-rays by air is eliminated, resulting in the possibility for low Z element analysis down to Na.
A second micro-XRF scanning instrument has been developed in-house and has been named the MicroXRF spectrometer. The laboratory microprobe applies a Mo X-ray tube equipped with DCC optics in order to obtain a micro-focussed, monochromatic beam, yielding a good spatial resolution coupled with an excellent sensitivity.
Currently a cooperation between the UGCT and XMI research groups is running to develop and construct a multi-method X-ray based imaging instrument, integrating three different non-destructive 3D microanalysis techniques. These will include two XRF-based methodologies: XRF tomography and a confocal XRF station. The instrument, named Heracles, will be up-and-running in the fall of 2015.
Next to these instruments which remain in the laboratory environment, the XMI group has access to a mobile XRF/XRD setup for in situ analysis of e.g. cultural heritage objects (Surface Monitor, Assing S.p.A, Italy). The Surface Monitor allows both elemental analysis and phase identification.
Besides, the XMI research group also has access to two other laboratory XRF setups to perform specialized measurements, namely a PANalytical Epsilon3 instrument for bulk elemental analysis and a TXRF setup (TX2000, GNR) for trace elemental analysis down to the ppb level.