Graphene is a single layer of carbon atoms arranged in a honeycomb pattern. It is tremendously strong and is an exciting area of research for those seeking to integrate it into computer chips, though the structure of graphene lacks a bandgap, making it a poor conductor on its own. Though it can be modified to have a bandgap, it comes at the expense of the graphene’s integrity as a material.
A new material has been developed that is structurally similar to graphene, but it has a bandgap that could potentially make it a viable semiconductor. The research was conducted from a team from MIT and Harvard and was led by Mercea Dincă. The new material has been described in detail in a paper published in the Journal of the American Chemical Society.
A bandgap is an area solid of solid matter that does not support any electron state. For use in semiconductors, this area forces the electrons into a band of energy. The valence band is closest to the atom’s nucleus and keeps electrons tightly packed in. The outer conduction band allows electrons to travel more freely. If the bands overlap, the solid acts like a metal and electricity flows too freely. However, if the bands are too far apart, the electrons aren’t able to cross from one band to another and the material acts like an insulator. Achieving an appropriately sized bandgap allows the material to act as a semiconductor, in which the flow of electrons can be regulated.
This new material blends nickel with HITP, an organic compound, to form Ni3(HITP)2. Manufacturing this material is made easier due to its ability to self-assemble. It has a honeycomb structure, just like graphene. The honeycombs themselves are about 2 nanometers in diameter.
The Ni3(HITP)2 material has not been studied in two-dimensional sheets as of yet; it has only been studied in large amounts. However, Dincă states in a press release that the material should be even more conductive when it is flat, making future studies with the material quite optimistic. She also notes that this blend of nickel and HITP can be replicated and modified to make a vast family of materials with similar properties that could be determined on the atomic level. Some of these materials may even support exotic electronic states.
This material could be used to make small, thin computer chips, which are in high demand as the trend toward smaller electronics continues. Additionally, using different combinations of materials could allow the material to capture specific wavelengths of light, making effective solar cells that can store energy to be used on demand.