title: Enhanced Photocurrent Density by Spin-Coated NiO Photocathodes for N-Annulated Perylene-Based p-Type Dye-Sensitized Solar Cells.
abstract: The low photocurrent density of p-type dye-sensitized solar cells (p-DSSCs) has limited the development of high-efficiency tandem cells due to the inadequate light-harvesting ability of sensitizers and the low hole mobility of semiconductors. Hereby, two new "push-pull" type organic dyes (PQ-1 and PQ-2) containing N-annulated perylene as electron donor have been synthesized, where the PQ-2-based p-DSSCs show higher photoelectric conversion efficiency (PCE) of 0.316% owing to the higher molar extinction compared to of that PQ-1. Additionally, the photocurrent densities were remarkably increased from 2.20 to 5.85 mA cm(-2) for PQ-1 and 2.45 to 6.69 mA cm(-2) for PQ-2 by spin-coated NiO photocathode based-p-DSSCs, respectively. This results are ascribed to the enhancement of hole transport rate, dye-loading amounts and transparency of NiO films in comparison to that prepared by screen-printing method. Electrochemical impedance spectroscopy and theoretical calculations studies indicate that the molecular dipole moment approaching closer to the NiO surface shifts the quasi-Fermi level to more positive levels, improving open-circuit voltage (Voc). Intensity-modulated photocurrent spectroscopy illustrates that the hole transit time in NiO films prepared in spin-coating is shorter than that prepared by screen-printing method.
authors.affiliation: Key Laboratory for Advanced Materials, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science & Technology , 130 Meilong Road, Shanghai, 200237, PR China.
authors.forename: Xing
authors.initials: X
authors.lastname: Li
authors.affiliation: Key Laboratory for Advanced Materials, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science & Technology , 130 Meilong Road, Shanghai, 200237, PR China.
authors.forename: Fengtao
authors.initials: F
authors.lastname: Yu
authors.affiliation: Max Planck Institute for Polymer Research , Ackermannweg 10, D-55128, Mainz, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Stappert
authors.affiliation: Max Planck Institute for Polymer Research , Ackermannweg 10, D-55128, Mainz, Germany.
authors.forename: Chen
authors.initials: C
authors.lastname: Li
authors.affiliation: Key Laboratory for Advanced Materials, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science & Technology , 130 Meilong Road, Shanghai, 200237, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Key Laboratory for Advanced Materials, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science & Technology , 130 Meilong Road, Shanghai, 200237, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Yu
authors.affiliation: Division of Theoretical Chemistry and Biology, School of Biotechnology, KTH Royal Institute of Technology , SE-10691 Stockholm, Sweden.
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.affiliation: Division of Theoretical Chemistry and Biology, School of Biotechnology, KTH Royal Institute of Technology , SE-10691 Stockholm, Sweden.
authors.forename: Hans
authors.initials: H
authors.lastname: Ågren
authors.affiliation: Key Laboratory for Advanced Materials, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science & Technology , 130 Meilong Road, Shanghai, 200237, PR China.
authors.forename: Jianli
authors.initials: J
authors.lastname: Hua
authors.affiliation: Key Laboratory for Advanced Materials, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science & Technology , 130 Meilong Road, Shanghai, 200237, PR China.
authors.forename: He
authors.initials: H
authors.lastname: Tian
keywords: N-annulated perylene; organic sensitizer; p-type dye-sensitized solar cells; quinoxaline; spin-coated NiO photocathode