1. Department of Materials Science Engineering; University of Ioannina; Ioannina 45110 Greece
2. Institute of Materials for Electronics and Energy Technology (I-MEET); Friedrich-Alexander-University Erlangen-Nuremberg; Martensstraße 7 91058 Erlangen Germany
3. Bavarian Center for Applied Energy Research (ZAE Bayern); Haberstrasse 2a 91058 Erlangen Germany