Flexible displays, cost-efficient solar cells for a new era of energy production, futuristic lighting at home – all require thin layers with specific properties. Scientists at the INM – Leibniz Institute for New Materials are exploring new routes to such coatings in the project “NanoSPEKT”.

They are aiming at flexible and transparent coatings that conduct electricity particularly well. The researchers combine inorganic nanoparticles with polymers and rationally arrange the particles inside the composite. The research will lead to particle-containing inks and coating methods that yield thin films with improved properties at lower cost.

“Today, the structure of composite layers is random. It does not help to develop highly conductive particles for composites if they do not touch each other: The electrons have to tunnel through the gaps, and electric conductivity is lost,” says Tobias Kraus, head of the Structure Formation Group at INM. He and his colleagues strive to improve control of the distribution of the particles inside the layers.

It is already possible to coat large areas with conductive films, for example using so-called “roll-to-roll” production methods. The scientists at INM will use compatible methods to enable cost-efficient large-scale production. They study how the particles change in the composite during processing. “If we manage to pack the conductive nanoparticles more closely, the electrical conductivity of the film increases,” says the group leader. This may be achieved by gently sintering the particles inside the polymer.

“NanoSPEKT” is funded by the Federal Ministry of Education and Research (BMBF) with 2.5 million euros. As a project in the framework of the funding initiative “NanoMatFutur” of the BMBF, “NanoSPEKT” will be initially supported for four years, a period that can be extended.

The funding initiative “NanoMatFutur” is part of the framework program “Materials Innovations for Industry and Society” (WING). WING combines traditional materials research with research on chemical technologies and materials-specific nanotechnology. It is part of the High-tech Strategy of the Federal Government.