Strong acid treatment is regarded as the most effective approach to increase the electrical conductivity of poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) electrodes. However, the conventional soaking treatments of strong acids have drawbacks, including limited flexibility of PEDOT:PSS electrodes coated on thermoplastic underlying substrates, high preparation cost with large acid consumption, and moderate stability of flexible organic solar cells (OSCs). Herein, a unique and cost-effective fumigation treatment using trifluoromethanesulfonic acid (CF₃SO₃H) vapors is proposed. The CF₃SO₃H fumigation treatment leads to a highly conductive, smooth, homogeneous, and flexible PEDOT:PSS electrode. On the basis of the CF₃SO₃H-fumigated PEDOT:PSS electrodes, the inverted flexible OSCs yield a high power conversion efficiency (PCE) of 13.62%. Moreover, the flexible solar cells maintain most (≈91%) of the initial efficiency in long-term storage. This work provides a novel route to make solution-processed flexible OSCs simultaneously have a high PCE and good storage stability.

中文翻译：

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具有 PE​​DOT:PSS 电极的高效稳定柔性有机太阳能电池通过超强酸熏蒸处理

强酸处理被认为是提高聚（3,4-亚乙基二氧噻吩）：聚（4-苯乙烯磺酸盐）（PEDOT：PSS）电极电导率的最有效方法。然而，传统的强酸浸泡处理存在缺陷，包括涂覆在热塑性底层基材上的 PEDOT:PSS 电极的柔韧性有限、制备成本高且酸消耗量大，以及柔性有机太阳能电池 (OSC) 的稳定性中等。在此，提出了一种使用三氟甲磺酸 (CF ₃ SO ₃ H) 蒸气的独特且具有成本效益的熏蒸处理方法。CF ₃ SO ₃H 熏蒸处理导致高导电、光滑、均匀和灵活的 PEDOT:PSS 电极。基于 CF ₃ SO ₃ H 熏蒸的 PEDOT:PSS 电极，倒置柔性 OSC 产生 13.62% 的高功率转换效率 (PCE)。此外，柔性太阳能电池在长期储存中保持大部分（≈91%）的初始效率。这项工作为使溶液处理的柔性 OSC 同时具有高 PCE 和良好的储存稳定性提供了一条新途径。