“We can fabricate multi-layer grids composed of different materials in virtually any geometric configuration,” said study coauthor and Brookhaven Lab scientist Kevin Yager.
“By quickly and independently controlling the nanoscale structure and the composition, we can tailor the performance of these materials. Crucially, the process can be easily adapted for large-scale applications.”
The results, published online in the journal Nature Communications could transform the manufacture of high-tech coatings.
The new technique relies on polymer self-assembly, where molecules are designed to spontaneously assemble into desired structures. Self-assembly requires a burst of heat to make the molecules snap into the proper configurations.
The Brookhaven researchers used an intensely hot laser and swept it across disordered polymer blocks that formed in precise arrangements in just seconds.
“Self-assembled structures tend to automatically follow molecular preferences, making custom architectures challenging,” said lead author Pawel Majewski, a postdoctoral researcher at Brookhaven.
“Our laser technique forces the materials to assemble in a particular way. We can then build structures layer-by-layer, constructing lattices composed of squares, rhombuses, triangles, and other shapes.”
Study coauthor Atikur Rahman said it was possible to use the technique to stack metals on insulators, too, embedding different functional properties and interactions within one lattice structure.
“The size and the composition of the mesh make a huge difference,” Rahman continued. “For example, a single layer of platinum nano-wires conducts electricity in only one direction, but a two-layer mesh conducts uniformly in all directions.”