The severe aggregation property of the small molecule electron‐transporting layer (ETL) not only deteriorates the photovoltaic performance and operational reliability but also constrains its compatibility with large‐scale coating techniques. Herein, by applying N,N′‐Bis{3‐[3‐(Dimethylamino)propylamino]propyl}perylene‐3,4,9,10‐tetracarboxylic diimide (PDINN) (a well‐known ETL) as a demo, a solvent‐induced anti‐aggregation (SIAA) strategy is proposed to cope with these hurdles via the mixing of ethanol and trifluoroethanol solvents at an optimal volume ratio. In situ photoluminescence and dynamic light scattering synergistically reveals the suppressed aggregation behavior of the SIAA‐treated PDINN dispersion during the film‐forming process. Owing to this amendment, the film quality and electron‐transport capability of the PDINN layer are remarkably enhanced. In consequence, based on the PM6:L8‐BO system, a champion power conversion efficiency (PCE) of 19.0% together with an impressive fill factor of 80.6% is harvested. A 1 cm2 device with an excellent PCE of 16.6% is also fabricated using the doctor‐blading SIAA‐treated PDINN ink. More strikingly, this SIAA treatment impels better reliability under long‐term shelf‐lifetime and thermal stress periods. This work provides a promising and tractable approach to address the inherent self‐aggregation issue of electron‐transporting materials, which is beneficial for the development of efficient and stable organic optoelectronic devices.

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Four natural chalcones, bartericin A (1), 2',6'-dihydroxy-5'-(2''-hydroxy-3''-methyl-3''-butenyl)-4'-methoxychalcone (2), xanthohumol D (3) and angusticornin B (4) were synthesized for the first time and all of them shared 5'-hydroxyisoprenyl group in common. One of their deriative, compound 6, was also prepared in order to investigate the effect of different functional group in natural products on antibacterial activity of the core structure. After confirming their structures by 1 H NMR, 13 C NMR, IR and HRMS, 1～4 and 6 were evaluated for their antibacterial activities against Bacillus subtilis [CMCC(B)63 501], Staphylococcus aureus [CMCC(B)260003], Escherichia coli [CMCC(B)44102] and Pseudomonas aeruginosa [CMCC(B)10104].In this assay micro-dilution method was employed. The results showed that compounds 1, 4 and 6 exhibited moderate activity against gram-positive bacteria Bacillus subtilis and Staphylococcus aureus. Meanwhile compound 3 showed significant activity towards Bacillus subtilis but no activity to the other 3 strains even in 200 μg/mL concentration.

The elaborate balance between the open‐circuit voltage (VOC) and the short‐circuit current density (JSC) is critical to ensure efficient organic solar cells (OSCs). Herein, the chalcogen containing branched chain engineering is employed to address this dilemma. Three novel nonfullerene acceptors (NFAs), named BTP‐2O, BTP‐O‐S, and BTP‐2S, featuring different peripheral chalcogen containing branched chains are synthesized. Compared with symmetric BTP‐2O and BTP‐2S grafting two alkoxy or alkylthio branched chains, the asymmetric BTP‐O‐S grafting one alkoxy and one alkylthio branched chains shows mediate absorption range, applicable miscibility, and favorable crystallinity. Benefiting from the enhanced π–π stacking and charge transport, an optimal power conversion efficiency (PCE) of 17.3% is obtained for the PM6:BTP‐O‐S‐based devices, with a good balance between VOC (0.912 V) and JSC (24.5 mA cm−2), and a high fill factor (FF) of 0.775, which is much higher than those of BTP‐2O (16.1%) and BTP‐2S‐based (16.4%) devices. Such a result represents one of the highest efficiencies among the binary OSCs with VOC surpassing 0.9 V. Moreover, the BTP‐O‐S‐based devices fabricated by using green solvent yield a satisfactory PCE of 17.1%. This work highlights the synergistic effect of alkoxy and alkylthio branched chains for high‐performance OSCs by alleviating voltage loss and enhancing FF.

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