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Herein, the properties of the organic heterostructures with triple‐layer ZnO/Ag/ZnO as a replacement for ITO and mixed layer containing arylenevinylene oligomer (based on triphenylamine or carbazole) donor and nonfullerene (perylene diimide) acceptor mixed in the ratio 1:2 and the effect of a buffer layer of PEDOT‐PSS intercalated between triple layer and mixed organic layer are discussed. The UV−vis transmission and photoluminescence (PL) properties are investigated in correlation with the surface topography and reveal a good match between the absorption and emission domain, which can favor the generation of the charge carriers. The heterostructure with the mixed layer based on triphenylamine oligomer shows the widest absorption domain, and the PL spectra of the heterostructures realized with either triphenylamine or carbazole oligomer show peaks corresponding to the radiative decay of the donor and acceptor. The I−V characteristics in the dark indicate a slightly nonlinear behavior and the current is affected by the charge carriers recombination on the defects present in the thick mixed layer deposited by matrix‐assisted pulsed laser evaporation. The effect of the PEDOT‐PSS buffer layer on the electrical properties of the organic heterostructure with ZnO/Ag/ZnO electrode is also investigated. [ABSTRACT FROM AUTHOR]

We investigated the optical and electrical properties of flexible single and bi-layer organic heterostructures prepared by vacuum evaporation with a p-type layer of arylenevinylene oligomers, based on carbazole, 3,3′ bis(N hexylcarbazole)vinylbenzene = L13, or triphenylamine, 1,4 bis [4 (N,N' diphenylamino)phenylvinyl] benzene = L78, and an n-type layer of 5,10,15,20-tetra(4-pyrydil)21H,23H-porphyne = TPyP. Transparent conductor films of Al-doped ZnO (AZO) with high transparency, >90% for wavelengths > 400 nm, and low resistivity, between 6.9 × 10−4 Ω·cm and 23 × 10−4 Ω·cm, were deposited by pulsed laser deposition on flexible substrates of polyethylene terephthalate (PET). The properties of the heterostructures based on oligomers and zinc phthalocyanine (ZnPc) were compared, emphasizing the effect of the surface morphology. The measurements revealed a good absorption in the visible range of the PET/AZO/arylenevinylene oligomer/TPyP heterostructures and a typical injection contact behavior with linear (ZnPc, L78) or non-linear (L13) J-V characteristics in the dark, at voltages < 0.4 V. The heterostructure PET/AZO/L78/TPyP/Al showed a current density of ~1 mA/cm2 at a voltage of 0.3 V. The correlation between the roughness exponent, evaluated from the height-height correlation function, grain shape, and electrical behavior was analyzed. Consequently, the oligomer based on triphenylamine could be a promising replacement of donor ZnPc in flexible electronic applications. [ABSTRACT FROM AUTHOR]