NovaCentrix Ink Powers Durable Antennas on Sustainable Nanofiber Substrates
The relentless growth of electronic devices has brought with it an escalating challenge: electronic waste. As the demand for connectivity expands, so does the imperative to develop more environmentally friendly materials and manufacturing methods for the next generation of electronics. Addressing this critical need, recent research published in Flexible and Printed Electronics highlights a significant step forward in sustainable printed electronics, demonstrating the successful fabrication of durable antennas on biobased substrates using NovaCentrix conductive inks.
In a study led by Jenny Wiklund and her colleagues, a coplanar waveguide-fed square slot antenna was aerosol jet printed onto acetylated cellulose nanofiber (ACNF) substrates. This innovative approach directly tackles the issue of e-waste by exploring sustainable alternatives to conventional plastic substrates like poly(ethylene terephthalate) (PET). The research meticulously investigated the functionality, print quality, and durability of these antennas, particularly under accelerated aging conditions, proving ACNF’s viability as a greener foundation for printed electronics.
Why Sustainable Substrates and Advanced Printing Matter
The sheer volume of e-waste is staggering, with 62 million tonnes produced globally in 2022, an 82% increase since 2010. This trend underscores the urgent need for sustainable materials and production techniques. Traditional electronic manufacturing often relies on non-renewable resources and generates substantial waste. Printed electronics, especially using additive manufacturing methods like aerosol jet (AJ) printing, offers a compelling solution by minimizing material waste and enabling the production of smaller quantities, ideal for prototyping and specialized applications.
However, choosing a sustainable substrate for printed electronics involves considering numerous factors, including cost, flexibility, non-toxicity, biodegradability, and resistance to environmental stressors like heat and UV radiation. While paper is an attractive biobased option, its inherent porosity and roughness often limit its suitability for high-performance electronics. Nanocellulose, and specifically acetylated cellulose nanofiber (ACNF), emerges as a promising candidate, offering improved material characteristics that overcome many of these limitations, making it a viable, durable alternative to plastics.
The Role of NovaCentrix Metalon® JS-A221AE Silver Nanoparticle Ink
Central to the success of this research was the selection of the right conductive material. The antennas in this study were fabricated using NovaCentrix’s Metalon® JS-A221AE silver nanoparticle ink. This advanced ink was specifically chosen for its optimal properties for aerosol jet printing, a non-contact additive manufacturing technique known for its ability to create fine-scale structures with high precision.
The researchers highlighted several key attributes of Metalon® JS-A221AE that were critical for this application:
- Favorable Surface Tension: With a surface tension of 29.9 mNm⁻¹, the ink demonstrated excellent wetting characteristics, crucial for achieving uniform and well-defined patterns on the substrate.
- Optimized Viscosity: A viscosity range of 10–20 cP ensured smooth and consistent flow through the aerosol jet printer, enabling precise deposition of the silver nanoparticles.
- Low-Temperature Sintering Capability: This property is vital for compatibility with heat-sensitive substrates like ACNF, allowing for the formation of highly conductive traces without damaging the underlying material.
These characteristics collectively enabled the direct printing of intricate antenna designs onto both ACNF and PET substrates, laying the groundwork for evaluating their performance and durability. NovaCentrix is committed to developing aerosol conductive inks that push the boundaries of what’s possible in printed electronics, facilitating research into next-generation sustainable devices.
Enabling Durable, High-Performance Antennas on ACNF
The study rigorously compared the print quality and electrical performance of antennas on ACNF and PET substrates, both before and after accelerated photodegradation. The results underscored the superior interaction of Metalon® JS-A221AE with the ACNF substrate. Optical microscopy revealed that the printed patterns on ACNF exhibited sharper edges and significantly fewer gaps compared to those on PET. This enhanced print quality on ACNF is attributed to its better wetting properties and higher polarity, which promote greater adhesion of the ink. Furthermore, the higher surface roughness of ACNF substrates contributed to improved ink adhesion and partial absorption, leading to a more robust printed layer.
Crucially, the electrical properties of the antennas on ACNF substrates were found to be nearly as good as those on PET before photodegradation. However, the true advantage of ACNF, enabled by the robust Metalon® JS-A221AE ink, became evident after accelerated aging. The photodegradation treatment, simulating nearly two years of natural exposure, caused a drastic increase in the sheet resistance of the PET-based antennas, leading to significant degradation in their microwave performance, including cracking and peeling of the coating. In stark contrast, the antennas printed on ACNF substrates showed only slight variations in sheet resistance and no notable changes in realized gain or efficiency. This remarkable durability highlights ACNF’s superior resistance to UV radiation and environmental degradation compared to conventional plastics.
Towards a Greener Future for Printed Electronics
This research provides compelling evidence that acetylated cellulose nanofiber (ACNF) is an excellent biobased alternative to plastic substrates for printed electronics. The ability to maintain high print quality and electrical performance, coupled with exceptional durability under accelerated aging, positions ACNF as a key material for sustainable electronic devices. The successful integration of NovaCentrix Metalon® JS-A221AE silver nanoparticle ink with ACNF substrates through aerosol jet printing demonstrates a viable pathway for manufacturing robust and environmentally conscious electronics.
As the industry continues its shift towards sustainability, materials like ACNF, combined with advanced conductive inks from NovaCentrix, will play a pivotal role. This work not only contributes to reducing electronic waste but also opens new avenues for developing flexible, durable, and high-performance printed devices for a wide range of applications, from IoT sensors to advanced communication systems. NovaCentrix remains at the forefront of this innovation, providing the materials that enable a greener, more connected future.
Read the full paper: Wiklund, J., Basnayaka, M., Miikki, K., Miettinen, A., Parkkonen, J., Xie, B., Karakoç, A., & Paltakari, J. (2026). Testing the durability of aerosol jet printed antennas on acetylated cellulose nanofiber substrates. Flexible and Printed Electronics, 11(1), 015003.