Graphene is a relative to graphite, which consists of millions of layers of graphene, and can be found in common pencil tips. Since graphene was isolated in 2004, researchers have learned to routinely produce and handle it. Graphene can be used to make electronic and optoelectronic devices such as transistors, photodetectors, and sensors.
A process was developed that enables graphene, a single-atom-thin layer of carbon, to be forged into three-dimensional objects using laser light. A pyramid with a height of 60 nm — about 200 times larger than the thickness of a graphene sheet — was fabricated using the process. The pyramid was so small that it would easily fit on a single strand of hair.
The optical forging technique resembles forging metals into 3D shapes with a hammer. In this case, a laser beam is the hammer that forges the graphene into 3D shapes. The technique is fast and easy to use, and does not require any additional chemicals or processing.
When the irradiated graphene was first examined, researchers expected to find traces of chemical species incorporated into the graphene, but there were none. After more careful inspection, it was concluded that it was purely structural defects, rather than chemical doping, that were responsible for such changes on the graphene.
The novel 3D graphene is stable and has electronic and optical properties that differ from normal 2D graphene. Optically forged graphene can help in fabricating 3D architectures for graphene-based devices.