... processing of large-scale graphene Nat Nanotech 2009, 4:25-29 doi:10.1186/1556-276X-7-53 Cite this article as: Kim et al.: Fabrication and characterization of carbon-based counter electrodes prepared by ... graphene, SWNTs, and graphene-SWNT composites could perform sufficiently well as counter electrodes for DSSCs Figure Nyquist plot of DSSCs Nyquist plot of DSSCs with different counter electrodes: ... 535-bisTBA, Solaronix, Aubonne, Switzerland) with a concentration of 0.5 mmol/L in ethanol for a period of 36 h at room temperature After that time, the TiO2 electrode and counter electrode were sandwiched...