Next-generation supercapacitors and solar cells could be improved by a newly-created germanium sulfide (GeS) nanomaterial resembling a shish-kebab.
North Carolina State University researchers put up a three-dimensional structure that consists of multiple bi-dimensional nanosheets impaled by a one-dimensional nanowire of germanium sulfide.
To create the heterosurface, the researchers begin by creating the nanowire 100 nanometers in width. After it’s exposed to air, the nanowire grows the so-called “nucleation sites” (see link) through weak oxidation. The two-dimensional nanosheets are then created by exposition to GeS vapors, which form at each of the nucleation sites (image).
This “heterostructure,” as they’ve called it, has a large surface area and, because it’s made from GeS, can act as a semiconductor. The GeS sheets provide the surface area and the nanowire is the link between them, transferring the electrical charges in between or to another surface. This can be used to make 3D solar cells or supercapacitors (because of the high surface area, they can hold more charge).
Dr. Linyou Cao, an assistant professor of materials science and engineering at NC State and co-author of a paper on the research says such heterostructures can also be created from other materials presenting similar crystalline layers, such as molybdenum sulfide (MoS2), and that they’re working on it.
The material invented by Cao and his team is also cheap to make. It could also be scaled up for industrial uses.