1. Laboratory for MEMS Applications (IMTEK); Department of Microsystems Engineering; University of Freiburg; Georges-Koehler-Allee 103 79110 Freiburg Germany
2. Department of Chemistry; Simon Fraser University; 8888 University Drive Burnaby V5A-1S6 Canada
3. Institute and Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT); University of Freiburg; Georges-Koehler-Allee 105 79110 Freiburg Germany
4. Department of Chemical and Biological Engineering; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstr. 3 91058 Erlangen Germany
5. Hahn-Schickard; Georges-Koehler-Allee 103 79110 Freiburg Germany
6. Forschungszentrum Jülich GmbH; Helmholtz-Institute Erlangen-Nürnberg for Renewable Energy (IEK-11); Forschungszentrum Jülich; Egerlandstr. 3 91058 Erlangen Germany