Efficient crystalline silicon (c-Si) heterojunction solar cells with conductive poly(ethylene dioxythiophene):poly(styrene sulfonate)(PEDOT:PSS) and graphene oxide (GO) are demonstrated using device structures of c-Si/GO/PEDOT:PSS/Ag and c-Si/PEDOT:PSS:GO composite/Al. The power-conversion efficiency η increased from 8.76 to 9.27% under illumination of AM1.5 100 mW/cm2 simulated solar light by adjusting the GO thickness for the n-Si/GO/PEDOT:PSS heterojunction solar cells. η also increased to 10.6% for the n-Si/PEDOT:PSS:GO composite devices by adjusting the GO mixing concentration.
The GO addition to conductive PEDOT:PSS suppressed electron recombination and/or promoted the hole current at the anode. The soluble PEDOT:PSS:GO composite is promising as a hole-transporting transparent conducting layer for c-Si/organic junction photovoltaic applications. The uniform coating of poly(3-hexylthiophene-2,5-dily) (P3HT) and PEDOT:PSS on textured hydrophobic c-Si wafer was observed by the electrospray deposition. The textured related enhancement of the device performance is demonstrated (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)