Engineering the electrical properties of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) holds great potential for various applications such as sensors, thermoelectric (TE) generators, and hole transport layers in solar cells. Various strategies have been applied to achieve optimal electrical properties, including base solution post-treatments. However, the working mechanism and the exact details of the structural transformations induced by base post-treatments are still unclear. In this work, we present a comparative study on the post-treatment effects of using three common and green alkali base solutions: namely LiOH, NaOH, and KOH. The structural modifications induced in the film by the base post-treatments are studied by techniques including atomic force microscopy, grazing-incidence wide-angle X-ray scattering, ultraviolet–visible–near-infrared spectroscopy, and attenuated total reflectance Fourier-transform infrared spectroscopy. Base-induced structural modifications are responsible for an improvement in the TE power factor of the films, which depends on the basic solution used. The results are explained on the basis of the different affinity between the alkali cations and the PSS chains, which determines PEDOT dedoping. The results presented here shed light on the structural reorganization occurring in PEDOT:PSS when exposed to high-pH solutions and may serve as inspiration to create future pH-/ion-responsive devices for various applications.

对聚（3,4-亚乙基二氧噻吩）：聚（苯乙烯磺酸盐）（PEDOT：PSS）的电气特性进行工程设计在传感器、热电 (TE) 发生器和太阳能电池中的空穴传输层等各种应用中具有巨大的潜力。已应用各种策略来实现最佳电性能，包括碱溶液后处理。然而，由碱后处理引起的结构转变的工作机制和确切细节仍不清楚。在这项工作中，我们对使用三种常见和绿色碱碱溶液的后处理效果进行了比较研究：即 LiOH、NaOH 和 KOH。通过原子力显微镜、掠入射广角 X 射线散射、紫外-可见-近红外光谱和衰减全反射傅里叶变换红外光谱。碱引起的结构改性是提高薄膜 TE 功率因数的原因，这取决于所使用的基本解决方案。结果是基于碱性阳离子和 PSS 链之间的不同亲和力来解释的，这决定了 PEDOT 去掺杂。此处展示的结果阐明了 PEDOT:PSS 在暴露于高 pH 溶液时发生的结构重组，并可能启发为各种应用创建未来的 pH/离子响应设备。碱引起的结构改性是提高薄膜 TE 功率因数的原因，这取决于所使用的基本解决方案。结果是基于碱性阳离子和 PSS 链之间的不同亲和力来解释的，这决定了 PEDOT 去掺杂。此处展示的结果阐明了 PEDOT:PSS 在暴露于高 pH 溶液时发生的结构重组，并可能启发为各种应用创建未来的 pH/离子响应设备。碱引起的结构改性是提高薄膜 TE 功率因数的原因，这取决于所使用的基本解决方案。结果是基于碱性阳离子和 PSS 链之间的不同亲和力来解释的，这决定了 PEDOT 去掺杂。此处展示的结果阐明了 PEDOT:PSS 在暴露于高 pH 溶液时发生的结构重组，并可能启发为各种应用创建未来的 pH/离子响应设备。