The Beauty of the Different Views on Diffusion
|Periodical||Defect and Diffusion Forum (Volumes 326 - 328)|
|Main Theme||Diffusion in Solids and Liquids VII|
|Edited by||Andreas Öchsner, Graeme E. Murch, Ali Shokuhfar and João M.P.Q. Delgado|
|Citation||Jörg Kärger, 2012, Defect and Diffusion Forum, 326-328, 1|
|Online since||April, 2012|
|Keywords||Interference Microscopy, IR Micro-Imaging, MRT, Nanoporous Materials, Propagator Representation, Pulsed Field Gradient NMR, Sticking Coefficients, Surface Barriers, Transport Vs. Self-Diffusion, Zeolites|
Guest diffusion in nanoporous materials reveals a wide spectrum of phenomena associated with random mass transfer in condensed matter quite in general. Taking advantage of their potentials for monitoring mass transfer over microscopic dimensions, micro-imaging (by interference microscopy and IR spectroscopy) and pulsed field gradient (PFG) NMR are exploited for providing typical examples highlighting these options. Starting with the surprise provided by the application of these microscopic measuring techniques to nanoporous materials, namely discrepancies of up to five orders of magnitude in comparison with the so far well-established data, the review covers some of the most impressive further results, including the determination of sticking coefficients on the surfaces of these materials and the specification and detection of conditions where molecular mass transfer is accelerated rather than hampered by counter fluxes.