Flexible organic solar cells (OSCs), especially ultra-flexible OSCs, show great potential for applications in wearable devices and related fields. However, improving their performance remains a significant challenge in the flexible OSC field. Despite its importance as a key component in flexible devices, the flexible substrate has received relatively little attention, which indeed hinders further improvement in flexible OSC performance. In this study, we developed an eco-friendly, ultra-flexible substrate with high solvent resistance, outstanding mechanical durability, and excellent light transmittance by constructing an ethoxylated trimethylolpropane triacrylate (ETPTA) polymer network within an ethyl cellulose (EC) film. OSCs fabricated on this substrate achieved a record power conversion efficiency (PCE) of 18.71% and a high power-per-weight ratio of 30.04 W g⁻¹. Furthermore, the ultra-flexible OSCs demonstrated excellent mechanical resilience, retaining 93.47% of their initial efficiency after 10 000 bending cycles at a bending radius of 1 mm.

中文翻译：

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基于环保纤维素基材的超柔性有机太阳能电池，效率接近 19%


柔性有机太阳能电池 （OSC），尤其是超柔性 OSC，在可穿戴设备和相关领域的应用潜力巨大。然而，在柔性 OSC 领域，提高其性能仍然是一个重大挑战。尽管柔性衬底是柔性器件中的重要组件，但其受到的关注相对较少，这确实阻碍了柔性 OSC 性能的进一步提高。在这项研究中，我们通过在乙基纤维素 （EC） 薄膜内构建乙氧基化三羟甲基丙烷三丙烯酸酯 （ETPTA） 聚合物网络，开发了一种环保、超柔韧的基材，具有高耐溶剂性、出色的机械耐久性和出色的透光率。在这种衬底上制造的 OSC 实现了创纪录的 18.71% 的功率转换效率 （PCE） 和 30.04 W ^g-1 的高功率单位重量比。此外，超柔性 OSC 表现出优异的机械弹性，在 1 mm 的弯曲半径下经过 10 000 次弯曲循环后，仍能保持 93.47% 的初始效率。