Charge transfer from poly(3-hexylthiophene) to graphene oxide and reduced graphene oxide

The energy levels of graphene oxide (GO) and reduced graphene oxide (rGO) were estimated in this work. We demonstrate that the energies of the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO) of GO become closer to each other upon reduction. GO and rGO were blended with poly(3-hexylthiophene) (P3HT) to form composite films and their optoelectronic properties were evaluated. It was found that both electrons and holes from photoexcited P3HT can transfer to rGO leading mostly to recombination while only electrons transfer to GO.