Direct Printing of Metal Nanoparticles on Stretchable Polymer Substrates for Wearable Applications
Board Location: #106
Discipline: Technology and Engineering
Subcategory: electrical/computer
Session: 3
Fatima Diallo - Norfolk State University, Virginia
Co-Author(s): Jakayla Collins, Norfolk State University, Virginia; Shawn Strobel, Norfolk State University, Virginia; Soumadeep De, Norfolk State University, Virginia
The growing demand for wearable electronics has driven advancements in integrating conductive materials onto flexible, biocompatible polymer substrates. These substrates are highly suitable for health monitoring, soft robotics, and bioelectronics due to their optical clarity, stretchability, and adaptability. However, their hydrophobic nature and low surface energy present challenges for the direct deposition of conductive materials. Plasma-aided printing provides an innovative solution, enabling low-temperature deposition while preserving the substrate’s mechanical properties.
In this study, silver nanoparticle (AgNP) conductive structures were fabricated on polymer substrates using an atmospheric plasma-aided inkjet printer. The process employed a 95% argon and 5% hydrogen gas mixture to generate plasma and enhance adhesion and conductivity. Plasma parameters, including voltage and post-treatment passes, were systematically optimized. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses demonstrated that a plasma voltage of 17 kV produced smooth, uniform films with improved nanoparticle crystallinity and adhesion, achieving high conductivity. Higher voltages led to surface cracking and reduced film thickness due to plasma bombardment.
Dynamic stretching tests validated the mechanical durability of the conductive structures, which maintained functionality under 10% elongation over 1,000 cycles. Notably, the sample fabricated with 17 kV plasma voltage, two print passes, and two post-plasma treatments exhibited a low resistivity of 6.79 × 10⁻⁵ Ω·cm, demonstrating both excellent electrical performance and mechanical resilience. The combination of this low resistivity and the ability to endure repeated mechanical stress highlights the significant potential of plasma-printed structures for applications in wearable electronics.
Future work will explore integrating advanced materials such as graphene and conductive polymers to further enhance the scalability and performance of plasma-aided printing. This technology offers significant promise for applications in flexible circuits, smart health monitors, and next-generation wearable devices.
Funder Acknowledgement(s): This work was funded in part by the NSF grant # 2112595 CREST Center for Research and Education in Quantum Leap Science and Technology (CREQS). This project is also supported by the National Science Foundation: Award Number 2100930.
Faculty Advisor: Renny Edwin Fernandez, refernandez@nsu.edu
Role: My role in this research involved developing polymer substrates suitable for plasma-aided printing of conductive structures, ensuring optimal surface preparation for enhanced adhesion and conductivity.