No abstract

Conjugated polymers, which exhibit electrical and optical properties owing to the presence of conjugated π bonds along the polymer backbone, are semiconducting materials of utmost interest. However, their immiscibility in water imposes restrictions on their usage; they are typically processed using toxic and environmentally harmful organic solvents. To address these issues, research has focused on converting conjugated polymers into nanoparticle dispersions in water or alcohols. This strategy not only avoids toxic solvent usage but also enhances application utility. In this article, to provide a comprehensive understanding of conjugated polymer nanoparticles, we introduce two principal approaches for classifying nanoparticle formation strategies and their corresponding experimental methods: with respect to the particle formation mechanisms and their preparation methods; we will discuss six such methods. Then, we review three different applications of the conjugated polymer nanoparticles in the fields of electronics, energy, and bioimaging, associating their requirements for attaining superior device performance with the characteristics of each method, and accordingly discuss methodological perspectives for each application.

In recent years, ionic liquid (IL)‐based solid polymer electrolytes (SPEs) have attracted much attention as conducting or capacitive materials for stretchable electronics. To fabricate fast and mechanically robust electronic devices, the high ionic conductivity and high elastic toughness of the SPE are essential. However, it has been challenging to achieve both high ionic conductivity and high elastic toughness simultaneously because high ionic conductivity generally requires low crystallinity of the polymer chains. Herein, a facile strategy for fabricating highly conductive, mechanically robust, and thermally stable SPE is demonstrated. A glass fiber mesh and La0.57Li0.29TiO3 particles as dual‐supporters are introduced, and 1‐ethyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][TFSI]) and bis(trifluoromethylsulfonyl)amine lithium salt (LiTFSI) (having the same anion) as the dual salt in the polymer electrolyte is introduced. Consequently, the SPE exhibits a superior ionic conductivity of 2.4 × 10−2 S cm−1 at room temperature and an outstanding elastic toughness of ≈170.3 kJ m−2. Finally, the dual‐salt/dual‐supporter SPE is successfully applied to high‐performance organic electrolyte‐gated transistors as gate dielectric materials and highly sensitive capacitive pressure sensors as force‐sensitive dielectric layers.

No abstract

Achieving high mobility and bias stability is a challenging obstacle in the advancement of organic thin-film transistors (OTFTs). To this end, the fabrication of high-quality organic semiconductor (OSC) thin films is critical for OTFTs. Self-assembled monolayers (SAMs) have been used as growth templates for high-crystalline OSC thin films. Despite significant research progress in the growth of OSC on SAMs, a detailed understanding of the growth mechanism of the OSC thin films on a SAM template is lacking, which has limited its use. In this study, the effects of the structure (thickness and molecular packing) of SAM on the nucleation and growth behavior of the OSC thin films were investigated. We found that disordered SAM molecules assisted in the surface diffusion of the OSC molecules and resulted in a small nucleation density and large grain size of the OSC thin films. Moreover, a thick SAM with disordered SAM molecules on the top was found to be beneficial for the high mobility and bias stability of the OTFTs.