1. Department of Physical and Chemical Sciences, University of L’Aquila 1 , via Vetoio (Coppito 1), L’Aquila 67010, Italy
2. Department of Civil, Environmental and Geomatic Engineering, Institute of Environmental Engineering, ETH Zürich 2 , Laura-Hezner-Weg 7, 8093 Zürich, Switzerland
3. Department of Chemical and Technological Sciences, University of Rome “Tor Vergata,” 3 Via della Ricerca Scientifica, I-00185 Rome, Italy
4. Center S3, CNR-Institute of Nanoscience 4 , Via Campi 213/A, 41125 Modena, Italy