Fig. 4From: Design and application of carbon nanomaterials for photoactive and charge transport layers in organic solar cells a A schematic depiction of the nitrogen doping process of reduced graphene oxide (RGO) and b a bulk heterojunction (BHJ) organic solar cell (OSC) made using a N-doped graphene/poly-3-hexylthiophene (P3HT):6,6-phenyl-C61-butyric acid methyl ester (PCBM) photoactive layer. Reprinted with permission from Jun et al. [47], © 2013, RSCBack to article page