Inkjet-deposited single-wall carbon nanotube micropatterns on stretchable PDMS-Ag substrate-electrode structures for Piezoresistive strain sensing

Abstract Printed piezoresistive strain sensors based on stretchable roll-to-roll screen-printed silver electrodes on polydimethylsiloxane substrates and inkjet-deposited single-wall carbon nanotube micropatterns are demonstrated in this work. With the optimization of surface wetting and inkjet printing parameters, well-defined microscopic line patterns of the nanotubes with a sheet resistance of <100 Ω/□ could be deposited between stretchable Ag electrodes on the plasma-treated substrate. The developed stretchable devices are highly sensitive to tensile strain with a gauge factor of up to 400 and a pressure sensitivity of ∼0.09 Pa–1, respond to bending down to a radius of 1.5 mm, and are suitable for mounting on the skin to monitor and resolve various movements of the human body such as cardiac cycle, breathing, and finger flexing. This study indicates that inkjet deposition of nanomaterials can complement well other printing technologies to produce flexible and stretchable devices in a versatile manner

Reliability of R2R-printed, flexible electrodes for e-clothing applications

Abstract Conformable electrodes are essential for the development of flexible electronics or functional clothing, regardless of their application. Their reliable ability to transfer electric signals or serve as sensing elements in various conditions is vital for the advancement of wearables that will enhance our everyday life. In this research, we concentrate our efforts on the understanding of the influence of elongation and washing on roll-to-roll printed conductive electrodes of various shapes and materials. A large sample set provides data on the breaking mechanisms and how these affect the electrical properties of the electrodes. In addition, the physicochemical analysis offers insights into the electrodes’ and materials’ behavior in extreme conditions during elongation and washing cycles. The achieved results indicate auspicious nanoparticle shapes and sizes as well as evidence regarding micro-scale breaking mechanisms responsible for electrodes degradation. Utilization of commercially available materials and roll-to-roll printing techniques allow the seamless application of achieved results and the creation of more reliable, flexible electronic devices

Influence of elongation and washing on double-layer R2R-printed flexible electrodes for smart clothing applications

Abstract Flexible electrodes are crucial for the growth of modern flexible electronics or smart clothing. Their ability to serve as sensing elements, deliver energy or transmit electrical signals in different conditions is essential for the evolution of wearables that will enrich our everyday life. In this study, we focus our efforts on understanding the impact of an additional protective layer on elongated and washed roll-to-roll printed (R2R) conductive flexible electrodes of various shapes. The electrical and morphological examinations provide information on the performance of the electrodes and materials during washing and elongation cycles. The acquired results indicate propitious electrode shapes as well as data concerning micro-scale cracking mechanisms, which are responsible for electrode performance degradation. The application of commercially available pastes and R2R printing methods allow the flawless utilization of the results and the fabrication of flexible and more reliable electronic components