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Five different indium-tin-oxide free (ITO-free) polymer solar cell architectures provided by four participating research institutions that all presented a laboratory cell performance sufficient for use in mobile and information and communication technology (ICT) were evaluated based on photovoltaic performance and lifetime tests according to the ISOS protocols. The comparison of the different device architectures was performed using the same active material (P3HT: PCBM) and tested against an ITO-based reference device. The active area was 1 cm2 and rigid glass or flexible polyester substrates were employed. The performance results were corroborated by use of a round robin methodology between the four participating laboratories (DTU/DK, ECN/NL, Frauenhofer ISE/DE, and the Holst Centre/NL), while the lifetime testing experiments were carried out in only one location (DTU). Five different lifetime testing experiments were carried out for a minimum of 1000 h: (1) shelf life (according to ISOS-D-1); (2-3) stability under continuous 1 sun illumination (1000 Wm-2, AM1.5G) at low (37 ± 3°C) and high (80 ± 5°C) temperatures (according to ISOS-L-1 and ISOS-L-2); (4) stability under continuous low-light conditions at 0.1 sun (100 Wm -2, AM1.5G, 32°C) (according to ISOS-LL); (5) continuous illumination (670 Wm-2, AM1.5G) at high temperature (65°C) and high humidity (50% RH) (according to ISOS-L-3). Finally, the upscaling compatibility of these device architectures based on the device photovoltaic behavior, stability and scalability were identified and we confirm that an architecture that presents a high score in only one aspect of the solar cell performance is not sufficient to justify an investment in upscaling. Many will require further technical development

Conventional lithographic printing processes using porous alumina for offset applications generally use "wet" routes. Recently "dry" processes have been developed which are based on a heat-induced hydrophilic/oleophilic conversion of one or more layers of the coating so that a stronger affinity towards ink or water fountain is created at the exposed areas with respect to the surface of the unexposed coating. Treatments involving rf plasma-enhanced fluorination (PEF) constitute exceptional tools for modifying the surface properties of materials. Many advantages of these techniques can be indeed outlined, when compared to more conventional methods: room-temperature reactions, chemical modifications limited to surface only without changing the bulk properties, possible non-equilibrium reactions. The influence of PEF treatments on porous alumina layer used in printing plates has been tested with various fluorinated gases (CF 4 , C 3 F 8 and C 4 F 8 ) and characterized by XPS. The hydrophobic properties of the fluorinated layer have been deduced from contact angle measurements. Using C 4 F 8 rf-PEF treatment, the outmost surface of the hydrophilic alumina substrate used for lithographic printing is hydrophobized, or in other words, the hydrophilic substrate is converted into a support with hydrophobic properties. Once being hydrophobized, the surface layer may be rendered hydrophilic using a heat pulse, thus giving rise to switchable hydrophobic-hydrophilic properties of the material. porous alumina, rf-plasma fluorination, offset applications, hydrophobic-hydrophilic, switchable layer, XPS, contact angle

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Large-scale production of organic photovoltaics (OPVs) at low cost is, still, a future concept thought to promote the market share of solar energy. Working towards the roll-to-roll production of OPVs, different compatible deposition techniques are investigated. Inkjet printing is a promising candidate, as it allows the contact-free deposition of patterned functional materials with high flexibility. In this article, we further extend the application of inkjet printing for roll-to-roll production of OPVs. Inkjet-printed high-conducting PEDOT:PSS is compatible with indium tin oxide-free devices, by combination with an Ag grid to form the anode. A P3HT/PCBM layer is inkjet printed on top using non-chlorinated halogen-free solvents only, and large-area homogeneous layers with surface areas up to 3 cm by 3 cm were obtained. The device thus manufactured showed performance comparable to a reference device with spin-coated layers for which chlorobenzene was used as solvent for the photoactive layer. This is an essential step forward in the knowledge on materials and process conditions using inkjet printing for OPVs and working towards the full roll-to-roll production of OPVs without loss of performance.