Several high performance polymer:fullerene bulk-heterojunction photo-active layers, deposited from the non-halogenated solvents o-xylene or anisole in combination with the eco-compatible additive p-anisaldehyde, are investigated. The respective solar cells yield excellent power conversion efficiencies up to 9.5%, outperforming reference devices deposited from the commonly used halogenated chlorobenzene/1,8-diiodooctane solvent/additive combination. The impact of the processing solvent on the bulk-heterojunction properties is exemplified on solar cells comprising benzodithiophenethienothiophene co-polymers and functionalized fullerenes (PTB7:PC71BM). The additive p-anisaldehyde improves film formation, enhances polymer order, reduces fullerene agglomeration and shows high volatility, thereby positively affecting layer deposition, improving charge carrier extraction and reducing drying time, the latter being crucial for future large area roll-to-roll device fabrication.

All‐solution deposited, ITO‐free organic solar cells comprising hybrid top and bottom electrodes and ternary polymer:fullerene photo‐active layers are investigated. A printed micro silver mesh and conductive PEDOT:PSS are employed as bottom electrode on a mechanically flexible PET substrate, whereas the top electrode features highly conductive PEDOT:PSS with dispersed silver nanowires. The highly efficient ternary polymer:fullerene absorber blend PffBT4T‐2OD:PC61BM:PC71BM and all other functional layers are doctor bladed from non‐halogenated solvents in order to comply with the requirements of industrial device fabrication. The semi‐transparent solar cells yield maximum power conversion efficiencies of 6.6% on active areas ≤ 0.1 cm2 and 5.9% on active areas > 1 cm2. Omitting additional bus bars for charge extraction grants the solar cells a homogeneous appearance and transparency perception.

We report on solution‐processed, semitransparent organic solar cells that are implemented as lenses in sunglasses. The electrical power provided by the lens‐fitted solar cells sustains a microelectronic circuit that is used to read out temperature and illumination intensity sensors and to make this information available on two displays integrated into the temples of the “Solar Glasses”. The microelectronic circuit is designed to operate at illumination intensities down to 500 lux, rendering the Solar Glasses suitable for outdoor and indoor use as well as for operation in diffuse light. Hence, this case study provides an example for consumer‐oriented mobile applications, self‐powered by integrated solar cells, which specifically exploit the unique properties of organic solar cells.

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