Nitrogen‐Doped Graphene Foams as Metal‐Free Counter Electrodes in High‐Performance Dye‐Sensitized Solar Cells

Efficient without metal: Nitrogen-doped graphene foams with a nitrogen content up to 7.6 % have been prepared and used as counter electrodes in dye-sensitized solar cells (DSSCs; see picture). The doping with nitrogen leads to a power conversion efficiency of 7.07 %. This is one of the highest values reported for DSSCs with carbon-based metal-free counter electrodes.