Highly Stretchable, Conductive, and Transparent PDMS Island‐Continuous PEDOT:PSS Matrix Composite Electrodes

Abstract

A polymer component in immiscible polymer blends results in phase separation, leading to polymer morphologies that vary from isolated spherical particles to a continuous matrix phase depending on the polymer weight ratio. This work demonstrates that a polymer component with a low weight fraction can form a continuous matrix phase, rather than isolated spherical particles, which is unprecedented. Bar‐coating a solution of poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) blended with a high fraction of polydimethylsiloxane (PDMS) and a surfactant results in a continuous PEDOT:PSS matrix distributed with spherical PDMS islands. The PEDOT:PSS and PDMS in the coated layer phase separate, forming a bilayer structure owing to its different affinities to the poly(ethylene terephthalate) (PET) substrate. When cured at 100 °C, water and other volatiles in the PEDOT:PSS phase in the bottom layer evaporate, generating spaces that are subsequently filled with PDMS from the phase‐separated top layer. The continuous PEDOT:PSS matrix ensures excellent conductivity (66.17 Ω·sq−1), while the PDMS islands provide high stretchability. The electrical conductivity of the new electrodes varies negligibly when stretched at 50% strain and is even maintained up to 150% strain. The electrodes exhibit high transparency (≈90% at 550 nm) and electromechanical stability over 1000 cycles of 30% stretch/release tests.

Flexible Transparent Electrode Based on Ag Nanowires: Ag Nanoparticles Co-Doped System for Organic Light-Emitting Diodes

“…Graphene is a material with high light transmittance, high electrical conductivity, and excellent flexibility, but its high cost makes it difficult to achieve the large-scale industrial production of graphene FTEs [10,11]. Conductive polymers, especially poly (3,4-ethylenedioxythiophene): poly (styrenesulfonate) (PEDOT: PSS), have high transmittance, high mechanical flexibility, and excellent thermal stability in the visible light range [12,13]. Metal nanowires, especially silver nanowires (Ag NWs), are inexpensive to synthesize and have high conductivity, so they are considered some of the most ideal materials for processing FTEs [14,15].…”