1. Catalonia Institute for Energy Research (IREC), Jardins de les Dones de Negre 1, Sant Adrià
del Besòs, 08930 Barcelona, Spain
2. Universitat de Barcelona (UB), Martí
i Franquès, 1, 08028 Barcelona, Spain
3. Repsol Technology Center, Agustín
de Betancourt, s/n, Móstoles, 28935 Madrid, Spain
4. Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, 08193 Barcelona, Spain
5. ICREA, Pg. Lluís
Companys 23, 08010 Barcelona, Spain