Hamburg University and Deutsches Elektronen-Synchrotron (DESY) scientists have utilized a new technique to 3D print flexible electronic circuits.
The circuits feature a mesh of silver nanowires that can be printed in suspension and embedded in various flexible and transparent plastics.
According to Hamburg’s Tomke Glier, the new technology could pave way for printable light-emitting diodes (LEDs), solar cells, flexible capacitors, and tools with integrated circuits.
“The aim of this study was to functionalize 3D printable polymers for different applications,” reports professor Michael Rübhausen from the Center for Free-Electron Laser Science (CFEL).
“With our novel approach, we want to integrate electronics into existing structural units and improve components in terms of space and weight.”
CFEL functions as a scientific collaboration between DESY, the University of Hamburg and the Max Planck Society.
Rübhausen led the project along with DESY researcher Stephan Roth, who is also professor at the Royal Institute of Technology in Stockholm.
Using the bright X-ray light from DESY’s research light source PETRA III and other measuring methods, the team precisely analyzed the properties of the nanowires in the polymer.
The silver wires are typically several tens of nanometers (millionths of a millimeter) thick and 10 to 20 micrometers (thousandths of a millimeter) long.
The detailed X-ray analysis shows that the structure of the nanowires in the polymer is not changed, but that the conductivity of the mesh even improves thanks to the compression by the polymer.
This is on account of the polymer contracting during the curing process. The silver nanowires are then applied to a substrate in suspension and dried.
“For cost reasons, the aim is to achieve the highest possible conductivity with as few nanowires as possible. This also increases the transparency of the material,” explains Roth.
The scientists have even applied a flexible polymer to the conductive tracks, which can be covered with conductive tracks and contacts.
They note that various electronic components can be printed in this way, depending on the geometry and material used.
Image and content: Tomke Glier/University of Hamburg, DESY