title: Significantly improved photovoltaic performance in polymer bulk heterojunction solar cells with graphene oxide /PEDOT:PSS double decked hole transport layer.
abstract: This work demonstrates the high performance graphene oxide (GO)/PEDOT:PSS doubled decked hole transport layer (HTL) in the PCDTBT:PC71BM based bulk heterojunction organic photovoltaic device. The devices were tested on merits of their power conversion efficiency (PCE), reproducibility, stability and further compared with the devices with individual GO or PEDOT:PSS HTLs. Solar cells employing GO/PEDOT:PSS HTL yielded a PCE of 4.28% as compared to either of individual GO or PEDOT:PSS HTLs where they demonstrated PCEs of 2.77 and 3.57%, respectively. In case of single GO HTL, an inhomogeneous coating of ITO caused the poor performance whereas PEDOT:PSS is known to be hygroscopic and acidic which upon direct contact with ITO reduced the device performance. The improvement in the photovoltaic performance is mainly ascribed to the increased charge carriers mobility, short circuit current, open circuit voltage, fill factor, and decreased series resistance. The well matched work function of GO and PEDOT:PSS is likely to facilitate the charge transportation and an overall reduction in the series resistance. Moreover, GO could effectively block the electrons due to its large band-gap of ~3.6 eV, leading to an increased shunt resistance. In addition, we also observed the improvement in the reproducibility and stability.
authors.affiliation: Low Dimensional Materials Research Centre, Department of Physics, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.|Centre of Nanotechnology, King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
authors.forename: Saqib
authors.initials: S
authors.lastname: Rafique
authors.affiliation: Low Dimensional Materials Research Centre, Department of Physics, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.|International Institute of Advanced Islamic Studies (IAIS) Malaysia, Jalan Ilmu, Off Jalan Universiti, 59100, Kuala Lumpur, Malaysia.
authors.forename: Shahino Mah
authors.initials: SM
authors.lastname: Abdullah
authors.affiliation: Low Dimensional Materials Research Centre, Department of Physics, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
authors.forename: Muhammad Mehmood
authors.initials: MM
authors.lastname: Shahid
authors.affiliation: Centre of Nanotechnology, King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
authors.forename: Mohammad Omaish
authors.initials: MO
authors.lastname: Ansari
authors.affiliation: Low Dimensional Materials Research Centre, Department of Physics, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
authors.forename: Khaulah
authors.initials: K
authors.lastname: Sulaiman