1. Bioinspired Structural Material Chemistry Institute of Interfacial Process Engineering and Plasma Technology University Stuttgart Nobelstr. 12 70569 Stuttgart Germany
2. Now at: Biogenic engineering materials Tu Bergakademie Freiberg Gustav‐Zeuner‐Str. 3 09599 Freiberg Germany
3. Physical Chemistry of Solids Max Planck Institute for Solid State Research Heisenbergstr. 1 70569 Stuttgart Germany