1. Laboratory of Inorganic Synthesis and Catalysis, Institute
of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne CH-1015, Switzerland
2. Laboratory for Nanoscale Materials Science, Swiss Federal Laboratories for Materials Science and Technology (EMPA), Dübendorf CH-8600, Switzerland
3. Photovoltaics and Thin-Film Electronics Laboratory, Institute of
Microengineering (IMT), Ecole Polytechnique Fédérale de Lausanne (EPFL), Neuchâtel CH-2000, Switzerland