Stable interface adhesion and bending durability of flexible organic solar cells (FOSCs) is a basic requirement for its real application in wearable electronics. Unfortunately, the device performance always degraded during continuous bending. Here, we revealed the weak interface adhesion force between MoO₃ hole transporting layer (HTL) and the organic photoactive layer was the main reason of poor bending durability. The insertion of an interface bonding layer with a thermoplastic elastomer, polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (SEBS) effectively improved the interface adhesion force of MoO₃ HTL and the active layer and decreased the modulus, which ensured higher than 90% of the initial efficiency remaining after 10000 bending. Meanwhile, the FOSCs gave an efficiency of 14.18% and 16.15% for the PM6:Y6 and PM6:L8-BO devices, which was among the highest performance of FOSCs. These results demonstrated the potential of improving the mechanical durability of FOSCs through thermoplastic elastomer interface modification.

柔性有机太阳能电池（FOSC）稳定的界面附着力和弯曲耐久性是其在可穿戴电子产品中实际应用的基本要求。不幸的是，在连续弯曲过程中，设备性能总是下降。在这里，我们揭示了MoO ₃空穴传输层（HTL）和有机光敏层之间较弱的界面粘附力是弯曲耐久性差的主要原因。插入具有热塑性弹性体聚苯乙烯-嵌段-聚(乙烯-冉-丁烯)-嵌段-聚苯乙烯(SEBS)的界面粘合层有效地提高了MoO _{3的界面粘合力}HTL 和活性层降低了模量，确保了 10000 次弯曲后剩余的初始效率高于 90%。同时，FOSC 对 PM6:Y6 和 PM6:L8-BO 器件的效率分别为 14.18% 和 16.15%，是 FOSC 中性能最高的。这些结果证明了通过热塑性弹性体界面改性提高 FOSC 机械耐久性的潜力。