1. Institute of General and Inorganic Chemistry, BAS; “Acad.G.Bonchev” str., Bl.11 1113 Sofia Bulgaria
2. Nanoparticle Process Technology; Faculty of Engineering and Center for Nanointegration Duisburg-Essen (CENIDE); University of Duisburg-Essen; Lotharstrasse 1 47057 Duisburg Germany
3. The Fuel Cell Research Center ZBT GmbH; Carl-Benz-Strasse 201 47057 Duisburg Germany
4. Acad. Evgeni Budevski Institute of Electrochemistry and Energy Systems, BAS; “Acad. G. Bonchev” str., Bl. 10 1113 Sofia Bulgaria