Combined Chemical and Thermal Sintering for High Conductivity Inkjet-printed Silver Nanoink on Flexible Substrates

Abstract

Electrical conductivity is a key factor in measuring performance of printed electronics,<br /> but the conductivity of inkjet-printed silver nanoinks greatly depends on post-fabrication<br /> sintering. In this work, two different conductive silver nanoinks, in which the silver nanoparticles were stabilized by two different capping agents – Poly(acrylic acid) (PAA) and Poly(methacrylic acid) (PMA) – were synthesized. The inks were inkjet-printed on flexible PET substrates, coated with an additional polycation layer, which facilitated<br /> chemical sintering. The printed features were then exposed to moderately elevated<br /> temperatures to evaluate the effect of combined chemical and thermal sintering. Both<br /> inks produced conductive features at room temperature, and the conductivity increased<br /> with both temperature and duration of sintering. At temperatures above 100 °C, the choice of capping agent had no pronounced effect on conductivity, which approached very high values of 50 % of bulk silver in all cases. The lowest resistivity (2.24 μΩ cm) was obtained after sintering at 120 °C for 180 min. By combining chemical and conventional thermal sintering, we have produced remarkably conductive silver electrodes on flexible substrates, while using low-cost and simple processes.

Recent Advances in (Bio)Chemical Sensors for Food Safety and Quality Based on Silver Nanomaterials

“…We can see that nanosensing is still a growing field with many possibilities for both food safety and quality sectors, albeit with remaining challenges towards successful commercialisation. While green AgNP synthetic routes are already being promoted, future breakthroughs may come from leveraging greener, versatile and high-throughput technologies for fabrication of solid-state nanoparticle-based sensors, such as screen printing or inkjet printing ( 142 ). Together with the observed trends in miniaturisation and automation, smart sensors (and smart packaging) were labelled as the future of the food industry.…”

Printed Electronics as Prepared by Inkjet Printing

“…The aim for a reduction in time and energy, and consequently process steps, has led to additional resources being invested in chemical sintering recently. With careful formulation of inkjet inks, the requirement for elevated temperatures as a post-printing finishing stage can be eliminated and instead replaced with a chemical immersion, which provokes nanoparticles to coalesce [108], or to moderately elevated temperatures ranging from 60-120 • C for 20 min [109]. Silver nanowires have recently been used to produce good performance flexible electrodes sintered under room temperature via different electrolyte solutions [110] on polycarbonate substrates.…”

Fabrication of an All-Solid-State Ammonium Paper Electrode Using a Graphite-Polyvinyl Butyral Transducer Layer

“…In order to fabricate an internal silver electrode, conductive nanosilver ink was loaded into the cartridge of a modified Epson Stylus D92 printer, and deposited onto paper substrate precoated with a polycation layer. The print settings were set as in our previous work [24,25]. Due to the presence of the polymer layer, the conversion of the inkjet-printed nanosilver suspension into its conductive form was performed by a room temperature sintering method.…”