Ionic Liquid Loaded Silica Gel Particles Studied by Spatially Resolved DBS Using a Scanning Positron Beam

Abstract:

The CDB-spectrometer at NEPOMUC enables spatially resolved Doppler Broadening Spectroscopy of the electron-positron annihilation line with a lateral resolution of up to 200~$\mu$m (FWHM). We have applied this technique for studying single particles of silica gel dependent on loading with an altering amount of the ionic liquid [C2MIM][NTf2]. Our results reveal a strong correlation between the observables of DBS and the loading factor which presumably arises from a smaller inner surface of voids in loaded silica gel.

• Periodical: Defect and Diffusion Forum (Volume 373)
• Pages: 80-83
• DOI: https://doi.org/10.4028/www.scientific.net/DDF.373.80
• Online since: March 2017
• Authors: Markus Reiner*, Hubert Ceeh, Thomas Gigl, Marco Haumann, Andreas Schönweiz, Christoph Hugenschmidt
• Keywords: Gels, Ionic Liquids, Micropores, Positron Annihilation, Silica

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