Fig. 6From: Design and application of carbon nanomaterials for photoactive and charge transport layers in organic solar cellsAtomic force microscopy (AFM) images of a graphene/poly-3-hexylthiophene (P3HT) and b graphene quantum dots (GQDs)/P3HT. Reprinted with permission from Gupta et al. [60], © 2011, ACS PublicationBack to article page