Intrinsically Stretchable Organic Solar Cells and Sensors Enabled by Extensible Composite Electrodes

Stretchable electrodes are critical to the development of advanced technologies such as human-machine interaction, flexible sensing, and wearable power supply, making them of significant research value. However, the current preparation methods for high-performance stretchable electrodes are complex and inefficient, posing challenges for their large-scale application in the realm of flexible wearables. To address this need, a straightforward and efficient embedding strategy is reported for fabricating stretchable silver nanowire/thermoplastic elastomer composite electrodes (referred to as Strem-AT) utilizing the viscoelasticity and outstanding mechanical properties of polymer elastomers to achieve outstanding extensibility, conductivity, and a smooth surface. These electrodes exhibit excellent tensile behavior, low surface roughness, and stable electrical properties, enabling their successful integration into stretchable sensors and intrinsically stretchable organic photovoltaic cells (IS-OPV). When applied to human skin joints for motion detection, the sensor demonstrates remarkable stretchability and stable signal output. Importantly, the all-polymer IS-OPV exhibits a top-notch power conversion efficiency (PCE) of >12.5% and a PCE80% strain exceeding 50%. Furthermore, even after subjecting high-strain stretching at 50% for 1000 cycles, the IS-OPV can retain 76% of the initial PCE. This study presents a multifunctional stretchable electrode with high repeatability and easy-to-scale fabrication in wearable sensors and photovoltaics.