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The article offers information on a study which examines ultratransparent poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate)(PEDOT:PSS) and silver (Ag) grid hybrid electrodes for organic photovoltaic (OPV) cells. An oxygen plasma etching process was performed to prepare the PEDOT:PSS thin films. It shows the potential of hybrid electrodes for effective OPV cells.

Highly transparent electrodes are demonstrated based on thermally evaporated calcium:silver blend thin-films, which show unusually high transmission well above the expectations from bulk material properties and thin film optics. These electrodes exhibit a low sheet resistance of 27.3 Ω/, combined with an extraordinarily high mean transmittance of 93.0% in the visible spectral range (σdc/σopt = 186.7), superior to the commonly used inorganic electrodes made from indium tin oxide (ITO). Additionally, the metal blend electrode is flexible, showing a constant sheet resistance down to a bending radius of 10 mm and can be employed on top of organic devices without causing damage to the organic material. The spontaneously formed unique microstructure of a polycrystalline Ag network with randomly distributed nanoapertures, surrounded by a calcium shell, enables broadband transmittance enhancement due to amplified plasmonic coupling. Consequently, top-illuminated organic solar cells using such metal blend electrodes achieve a power conversion efficiency of 7.2% (which defines a new record for top illuminated organic solar cells) and even exceed the efficiency of similar bottom-illuminated reference solar cells (6.9%) employing common ITO electrodes. [ABSTRACT FROM AUTHOR]

The great potential of solution-processed metal nanowire networks utilized as a transparent electrode has attracted much attention in the last years. Typically, silver nanowires are applied, although their replacement by more abundant and cheaper materials is of interest. Here, a hydrazine-free synthesis route for high aspect ratio copper nanowires is used to prepare conductive networks showing an enhanced electrode performance. The network deposition is done with a scalable spray-coating process on glass and on polymer foils. By a pressing or an annealing step, highly conductive transparent electrodes are obtained, and they reveal transmittance-resistance values similar to indium tin oxide (ITO) and networks made of silver nanowires. The application potential of the copper nanowire electrodes is demonstrated by integrating them into an evaporated small-molecule organic solar cell with 3% efficiency. [ABSTRACT FROM AUTHOR]

Efficient transparent organic light-emitting diodes (OLEDs) with improved stability based on conductive, transparent poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) electrodes are reported. Based on optical simulations, the device structures are carefully optimized by tuning the thickness of doped transport layers and electrodes. As a result, the performance of PEDOT:PSS-based OLEDs reaches that of indium tin oxide (ITO)-based reference devices. The efficiency and the long-term stability of PEDOT:PSS-based OLEDs are significantly improved. The structure engineering demonstrated in this study greatly enhances the overall performances of ITO-free transparent OLEDs in terms of efficiency, lifetime, and transmittance. These results indicate that PEDOT:PSS-based OLEDs have a promising future for practical applications in low-cost and flexible device manufacturing. [ABSTRACT FROM AUTHOR]

High performance indium tin oxide (ITO)-free small molecule organic solar cells and organic light-emitting diodes (OLEDs) are demonstrated using optimized ZnO electrodes with alternative non-metallic co-dopants. The co-doping of hydrogen and fluorine reduces the metal content of ZnO thin films, resulting in a low absorption coefficient, a high transmittance, and a low refractive index as well as the high conductivity, which are needed for the application in organic solar cells and OLEDs. While the established metal-doped ZnO films have good electrical and optical properties, their application in organic devices is not as efficient as other alternative electrode approaches. The optimized ZnO electrodes presented here are employed in organic solar cells as well as OLEDs and allow not only the replacement of ITO, but also significantly improve the efficiency compared to lab-standard ITO. The enhanced performance is attributed to outstanding optical properties and spontaneously nanostructured surfaces of the ZnO films with non-metallic co-dopants and their straightforward integration with molecular doping technology, which avoids several common drawbacks of ZnO electrodes. The observations show that optimized ZnO films with non-metallic co-dopants are a promising and competitive electrode for low-cost and high performance organic solar cells and OLEDs. [ABSTRACT FROM AUTHOR]

n‐Doped C60 is reported as a new electrode material for indium‐tin‐oxide‐free organic solar cells. All layers from the bottom to top electrode are prepared in one step in a vacuum chamber. The organic solar cells based on the n‐C60 electrodes assisted by a semitransparent metal grid exhibit efficiencies as high as 2.9%. [ABSTRACT FROM AUTHOR]

A hybrid electrode with a combination of an ultratransparent conductive polymer (nearly 100% transparency) and a semitransparent silver grid is developed for organic photovoltaic cells. In article number 1401822, Yong Hyun Kim and co‐workers report that the hybrid electrode shows an improvement of the photovoltaic performance and a potential to reduce a significant resistive power loss in large‐area devices. These hybrid electrodes will contribute the development of low‐cost, efficient, large‐area organic photovoltaic cells. [ABSTRACT FROM AUTHOR]