Identification of Degradation Mechanisms in Slot-Die-Coated Nonfullerene ITO-Free Organic Solar Cells Using Different Illumination Spectra Articles uri icon

authors

  • ARREDONDO CONCHILLO, BELEN
  • del Pozo Melero, Gonzalo
  • Hernández-Balaguera, Enrique
  • MARTIN MARTIN, DIEGO
  • López González, Maria del Carmen
  • ROMERO, BEATRIZ
  • LOPEZ FRAGUAS, EDUARDO
  • VERGAZ BENITO, RICARDO
  • QUINTANA, XABIER
  • Lamminaho, Jani
  • Destouesse, Elodie
  • Ahmadpour, Mehrad
  • Turkovic, Vida
  • Madsen, Morten

publication date

  • June 2020

start page

  • 6476

end page

  • 6485

issue

  • 7

volume

  • 3

International Standard Serial Number (ISSN)

  • 2574-0962

abstract

  • In this work, we have studied degradation mechanisms of nonfullerene-based organic solar cells with PET/Ag/ZnO/PBDTB-T:ITIC/PEDOT:PSS/CPP PEDOT:PSS device structure. We compare pristine and degraded samples that were subjected to outdoor degradation following the standard ISOS-O2 protocol. The ideality factors for different incident wavelengths obtained from open-circuit voltage vs irradiation level and current density–voltage (J–V) measurements at different temperatures indicate that for aged samples recombination is governed by the Shockley–Read–Hall mechanism occurring in a region near the anode. Samples were also characterized using impedance spectroscopy (IS) and fitted to an electrical model. Impedance parameters were used to obtain mobility, indicating a clear degradation of the active layer blend for aged samples. The change in the chemical capacitance also reveals a worsening in carrier extraction. Finally, two-dimensional (2D) numerical simulations and fits to experimental J–V curves confirm the existence of a layer near the anode contact with poorer mobility and a decrease in the anode work function (WF) for the degraded samples.

keywords

  • organic solar cells; degradation; nonfullerene; slot-die coating; ito-free; flexible