Recently, Rodney Loop, a professor of special science at the UNIST Department of Natural Science (IBS, director of the Multi-Dimensional Carbon Material Research Group) and his research team succeeded to synthesize ultra-thin diamond layer using graphene through an inexpensive and simple process for the first time in the world. They decreased the cost of synthesizing it by using fluorine and chemical vapor deposition.

▲ The picture of professor Rodney Loop and his UNIST research team

Both diamond and graphene are composed of a carbon atom. However, because of the difference of the combination structure between diamond and graphene, they have different properties. Diamond has excellent thermal conductivity and mechanical strength, but it cannot carry electricity and bond. On the other hand, graphene not only has great thermal conductivity and mechanical strength but also carries electricity and bond because it is a two-dimensional structure. So, the research that makes a diamond into a two-dimensional structure like graphene to use diamond's superb properties in many fields is active, and the diamond made with ultra-thin layer is called "Diamane." Yet, this research cannot reach commercialization because high temperature and pressure are fundamental to change the graphene's structure. This process is very expensive, and the diamane made by this process cannot keep stability at room temperature and air pressure.

▲ The comparison between double layer graphene and F-diamane

UNIST research team overcame this process and made a simple process. After they made double layer graphene on a copper-nickel alloy board, they injected fluorine gas to it using chemical vapor deposition. Injected fluorine induced to form a carbon combination between two graphene layers, having a chemical reaction with graphene. The carbon atoms combined with three atoms became a combination of four atoms. As a result, diamane, the film-shaped diamond, is finally made. The research team designated it "F-diamane" because they made it by using fluorine.

▲ The structure of F-diamane

This simple process can reduce the cost of making diamane sharply because this process proceeds at room temperature and air pressure. UNIST research team said that through synthesizing similar diamond structures, they can use diamond's magnificent properties in various fields. This research's result was run on Nature Nanotechnology.

Jan. 11th, 2020

by Lee Ji-eun