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Developing a high-performance donor polymer is critical for achieving efficient non-fullerene organic solar cells (OSCs). Currently, most high-efficiency OSCs are based on a donor polymer named PM6, unfortunately, whose performance is highly sensitive to its molecular weight and thus has significant batch-to-batch variations. Here we report a donor polymer (named PM1) based on a random ternary polymerization strategy that enables highly efficient non-fullerene OSCs with efficiencies reaching 17.6%. Importantly, the PM1 polymer exhibits excellent batch-to-batch reproducibility. By including 20% of a weak electron-withdrawing thiophene-thiazolothiazole (TTz) into the PM6 polymer backbone, the resulting polymer (PM1) can maintain the positive effects (such as downshifted energy level and reduced miscibility) while minimize the negative ones (including reduced temperature-dependent aggregation property). With higher performance and greater synthesis reproducibility, the PM1 polymer has the promise to become the work-horse material for the non-fullerene OSC community.

Smart dynamic regulation structured surfaces, inspired by nature, which can dynamically change their surface topographies under external stimuli for convertible fluidic and optical properties, have recently motivated significant interest for scientific research and industrial applications. However, there is still high demand for the development of multifunctional dynamically transformable surfaces using facile preparation strategies. In this work, a type of Janus high‐aspect‐ratio magnetically responsive microplates array (HAR‐MMA) is readily fabricated by integrating a flexible laser scanning strategy, smart shape‐memory‐polymer‐based soft transfer, and a simple surface treatment. By applying external magnetic field, instantaneous and reversible deformation of Janus HAR‐MMA can be actuated, so surface wettability can be reversibly switched between superhydrophobic (158°) and hydrophilic (40°) states, based on which a novel magnetically responsive water droplet switch can be realized. Moreover, inspired by the biological assimilatory coloration of chameleons, dynamically color conversion can be skillfully realized by applying different colors on each side of the Janus HAR‐MMA. Finally, as a proof‐of‐concept demonstration in light manipulation, a HAR‐MMA is applied as an optical shutter actuated by external magnetic field with eximious controllability and repeatability. The developed multifunctional HAR‐MMA provides a versatile platform for microfluidic, biomedical, and optical applications.

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Extensive studies in various plants show that the anthocyanin biosynthetic process is affected by environmental factors and regulated by many transcription factors through sophisticated regulatory networks. However, it remains largely unclear about the roles of microRNA in this process. Here, we demonstrate that miR858a is a positive regulator of anthocyanin biosynthesis in Arabidopsis seedlings. Overexpression of miR858a enhances the accumulation of anthocyanins, whereas the reduced miR858a activity results in low levels of anthocyanins in STTM858 transgenic plants. We found that miR858a inhibits the expression of MYBL2, a key negative regulator of anthocyanin biosynthesis, by translational repression. In addition, ELONGATED HYPOCOTYL 5 (HY5) was shown to directly bind the MYBL2 promoter and represses its expression via specific histone modifications. Interestingly, we found that miR858a exhibits light-responsive expression in an HY5-dependent manner. Together, these results delineate the HY5-MIR858a-MYBL2 loop as a cellular mechanism for modulating anthocyanin biosynthesis, suggesting that integration of transcriptional and posttranscriptional regulation is critical for governing proper anthocyanin accumulation in response to light and other environmental factors.

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