1. Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, Faculty of Chemistry and Mineralogy, University of Leipzig, D-04103 Leipzig, Germany, Center for Surface Chemistry and Catalysis, KU-Leuven, B-3001 Leuven (Heverlee), Belgium, Zeosorb GmbH, D-06749 Bitterfeld, Germany, and Department of Material Science, Technical University of Darmstadt, D-64287 Darmstadt, Germany