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The use of additives to improve the performance of organic photovoltaic cells has been intensely researched in recent years. However, so far, no system has been reported for the classification of additives and their functions. In this report, a system for classifying additives according to the fundamental mechanism by which they influence microstructure formation for P3HT:PCBM is suggested. The major parameters used for their classification are solubility and drying kinetics. Both are discussed in detail and their consequences on processing are analyzed. Furthermore, a general mechanism to classify the impact of additives on structure formation is suggested and discussed for different materials relevant to organic photovoltaic devices.

Colloidal nanocrystals from PbS are successfully applied in highly sensitive infrared photodetectors with various device architectures. Here, we demonstrate all-printed devices with high detectivity (∼10 12 cm Hz 1/2 /W) and a cutoff frequency of >3 kHz. The low material consumption (<0.3 mg per detector) and short processing time (14 s per detector) enabled by the automated printing promises extremely low device costs. To enable all-printed devices, an ink formulation was developed based on nanocrystals stabilized by perovskite-like methylammonium iodobismuthate ligands, which are dispersed in a ternary solvent. Fully inkjet printed devices based on this solvent were achieved with printed silver electrodes and a ZnO interlayer. Considerable improvements were obtained by the addition of small amounts of the polymer poly(vinylpyrrolidone) to the ink. The polymer improved the colloidal stability of the ink and its film-formation properties and thus enabled the scalable printing of single detectors and detector arrays. While photoconductors were shown here, the developed ink will certainly find application in a series of further electronic devices based on nanocrystals from a broad range of materials.

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One of the biggest attractions of the organic photovoltaics (OPV) technology is the easiness with which it can be integrated. However, despite its semitransparency and wide variety of colors, a major unresolved challenge is to fabricate optically inconspicuous organic photovoltaic modules (OPV‐M) that can be integrated into visually demanding products. This is dominantly due to the visual obstruction from Z‐interconnection lines inherent to module processing with classical patterning methods. We now present for the first time a solution to this problem, which utilizes a visually seamless interconnection method to elegantly minimize the conspicuity of the interconnection regime. We realize such invisible interconnects by inkjet printing highly conductive silver lines, which penetrate the solar cell stack and form an electrical connection between adjacent cells. A combined characterization approach utilizing in‐depth electrical characterization and finite element (FEM) simulation rationalizes the excellent electrical cell‐to‐cell contact established with this interconnection technology. We combine this technology with a variable‐geometry module design into an innovative digital inkjet printing platform for the production of state‐of‐the art but visually attractive solar modules. The full potential of this concept is demonstrated by a fully inkjet printed arbitrarily shaped OPV‐M portrait.

A novel strategy to overcome wetting problems is applied to manufacture inverted structure P3HT:O-IDTBR solar cells with 5% efficiency.

Urologic tumors are frequently treated by multimodal therapeutic strategies with the consequence of an increasing number of adverse events. The most common chemotherapy-induced side effects are neutropenia, stomatitis, mucositis, diarrhea, and emesis. The efficacy of tumor therapy can be improved by good prophylaxis and standardized management of side effects.

An important aspect when upscaling organic photovoltaics from laboratory to industrial scale is quality control. Established imaging techniques like lock‐in thermography or luminescence imaging are frequently used for this purpose. While these techniques allow for the lateral detection of defects, they cannot provide information on the vertical position of the defect in the OPV stack. Here, we present an approach to overcome this limitation. A femtosecond‐laser is deployed to introduce well‐defined artificial calibration defects selectively into both the interface and the bulk active layer of inverted P3HT:PCBM bulk heterojunction cells during device fabrication. The defective cells are then characterized using J‐V analysis and several nondestructive imaging methods (dark lock‐in thermography, photoluminescence, and electroluminescence imaging). The distinct response for each defect in the different imaging methods enables us to uniquely distinguish between bulk and interface defects. This allows to study surface recombination under most controlled conditions.