A team of KAUST engineers has managed to create a new type of printable ink with advanced conductivity and transparency tradeoff. This new ink will be used in solar panels, as well as for blocking electromagnetic waves from devices.
High-conductivity metals like copper and gold are often used in the electronics industry, as they generate very little heat when currents flow through them. Unfortunately, these high-conductivity materials have another thing in common: they are opaque, a trait that does not benefit electronic devices.
In order to create a material that combined high conductivity with transparency, the KAUST researchers developed a conductive ink by dispersing silver nanowires within a polymer solution. The engineers next enhanced the natural optical and electrical properties of the material by using a treatment called xenon flash-light sintering.
“Silver nanowires are typically patterned through multiple processing steps and the patterning size is quite limited. We demonstrate the large-area and high-throughput patterning of silver nanowires in a single step.”
Atif Shamim, electrical engineer
Researchers believe the ink could prove useful in a wide array of optoelectronic applications in a variety of industries. The ink has already proved effective at blocking electromagnetic waves from electronic devices. To do this, engineers created a frequency selective surface (FSS). This structure is capable of reflecting electromagnetic waves within a particular frequency; other waves can pass through unimpeded. The FSS was created by taking the conductive ink and applying it in a basic repeating pattern to a flexible polymer substrate.
Early results of testing indicate that FSS has a solid reflection performance across two bands in the electromagnetic spectrum that includes the radio frequency part. The KAUST FSS is also unique in that, unlike traditional FSSs, their design proved insensitive to radio wave polarization, and maintained a stable performance across a variety of different incidence angles.
In order to show the real-world application of their new creation, KAUST engineers covered a box with FSS and placed a mobile phone inside. From there, they observed a distinct reduction in the strength of the signal. The team of scientists see this as a promising start and intend to work on extending their applications for transparent, flexible, and high-performance electronic devices.
