Roozbeh Valadian

PhD Candidate

Employed since: February 2017
Phone: +31 620046961
E-Mail: r.valadian@uu.nl
Room: 4th floor open area

Project description

Main task of the project will be the application of non-destructive X-ray based high-resolution spectro-microscopic imaging methods and development of related data processing tools, with the aim to establish simple diffusion simulations by means of pore network modeling (PNM). Main microscopic methods will be synchrotron-based full field transmission X-ray microscopy(FF-TXM) and X-ray fluorescence XRF tomography ; it will be tested whether these established tools can be supplemented by X-ray diffraction imaging, namely ptychography (scanning coherent diffraction imaging), and X-ray holotomography to achieve even higher 3D resolution, aiming to break the 'meso-pore barrier' of 50nm.

Once experimental setup and methodological approach are established, fresh as well as aged industrial Ecat bodies will be studied. Based on the obtained results and provided the obtained signal-to-noise-ratio allows it, 3D TXM-XANES (X-ray absorption near edge structure) analysis will be applied to inspect the oxidation state or even the chemical species of the deposited metals. Metal accumulation is a key factor in catalyst deactivation and related to pore clogging that changes the accessibility of the catalyst.