In this study, we report the effects of graphene oxide as the multifunctional interfacial carrier transporting layers (CTLs) between the poly(3-hexylthiophene): poly(3-hexylthiophene): 3'H-cyclopropa [8,25] [5,6] fullerene-C60-D5h(6)-3'-butanoic acid 3'-phenyl methyl ester (P3HT:PCBM) layer and metal electrodes of organic solar cells. The composite of graphene oxide (GO) with zinc oxide (ZnO) (GO/ZnO) and with poly(3,4-ethylenedioxythiophene): poly (styrene sulfonate) (PEDOT:PSS) (GO/PEDOT:PSS was produced by grafting the ZnO and PEDOT:PSS onto GO sheets using a molecular level interconnections approach. The cross-linking and longitudinal binding of GO with ZnO and with PEDOT:PSS demonstrated a significant improvement in PCE (4.88%), reproducibility and environmental stability (40% after 432 hr).