PEDOT:PSS for Flexible and Stretchable Electronics: Modifications, Strategies, and Applications

Abstract

Substantial effort has been devoted to both scientific and technological developments of wearable, flexible, semitransparent, and sensing electronics (e.g., organic/perovskite photovoltaics, organic thin‐film transistors, and medical sensors) in the past decade. The key to realizing those functionalities is essentially the fabrication of conductive electrodes with desirable mechanical properties. Conductive polymers (CPs) of poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) have emerged to be the most promising flexible electrode materials over rigid metallic oxides and play a critical role in these unprecedented devices as transparent electrodes, hole transport layers, interconnectors, electroactive layers, or motion‐sensing conductors. Here, the current status of research on PEDOT:PSS is summarized including various approaches to boosting the electrical conductivity and mechanical compliance and stability, directly linked to the underlying mechanism of the performance enhancements. Along with the basic principles, the most cutting edge‐progresses in devices with PEDOT:PSS are highlighted. Meanwhile, the advantages and plausible problems of the CPs and as‐fabricated devices are pointed out. Finally, new perspectives are given for CP modifications and device fabrications. This work stresses the importance of developing CP films and reveals their critical role in the evolution of these next‐generation devices featuring wearable, deformable, printable, ultrathin, and see‐through characteristics.

Low-Temperature Growing Anatase TiO2/SnO2 Multi-dimensional Heterojunctions at MXene Conductive Network for High-Efficient Perovskite Solar Cells

“…The electron mobility (μ) is an important parameter to characterize semiconductive properties [59][60][61]. It can be obtained by SCLC measure with Eq.…”

An Efficient Ultra‐Flexible Photo‐Charging System Integrating Organic Photovoltaics and Supercapacitors

“…As one of the most classic and successful commercial available conducting polymers, PEDOT:PSS has many advantages such as easy processability, flexibility, and good electrical conductivity for flexible supercapacitors. [ 22 ] Here a sulfuric acid treatment, which can dramatically improve film conductivity and stability by removing the PSS component and initiating the formation of crystallized nanofibrils, was carried out to prepare more conductive and free‐standing thick PEDOT:PSS film at micrometer‐scale ( Figure 2 a). The film thickness and conductivity can be well‐tuned by the concentrated sulfuric acid treatment (Figure S1, Supporting Information), and a state‐of‐the‐art conductivity of 4464 S cm −1 was achieved for a film with a thickness of 2.1 µm, as shown in Figure 2b.…”

“…[ 23 ] The enhanced mechanical robustness after acid treatment could be attributed to the improved interconnection between polymer matrix and CNT networks through the interchain interaction in the films. [ 22 ] This dramatically enhanced film robustness not only favors better mechanical durability but also higher operational stability during the ion absorption and desorption, which is crucial to achieving superior stability in the supercapacitor. As a result, the capacitance of the as‐fabricated supercapacitor remains quite high under cyclic charge/discharge operation, maintaining 95.89% of its initial value after 10 000 cycles at a current density of 10 mA cm −2 , as shown in Figure 2h and Figure S9, Supporting Information.…”

Acidity Suppression of Hole Transport Layer via Solution Reaction of Neutral PEDOT:PSS for Stable Perovskite Photovoltaics

“…Table S1 shows the peak As the gel particle polymer composite in aqueous solution is deposited and annealed forming thin PEDOT:PSS film [43,[46][47][48][49], the PEDOT chains interact with the neighboring PEDOT-rich domains and bring the conducting domains closer by coalescence of PEDOT:PSS particles. The thermal annealing evaporates and softens PSS-rich domains, which improve connectivity and charge transport of conducting domains [47,50,51]. After the annealing and additional polymerization, the phase separation of PEDOT and PSS occurs.…”