Researchers from The University of Texas at Austin (UT Austin) used surface oxygen to grow centimeter-size single graphene crystals on copper. These are very large single crystals, that feature exceptional electrical properties, are about 10,000 times as large as the largest crystals made at the University only four years ago.
The researcher explain that they are controlling the growth of tiny graphene nuclei, and using Oxygen at the right surface concentration means only a few nuclei grow, and winners can grow into very large crystals. By increasing the single-crystal domain sizes, the electronic transport properties will be dramatically improved and lead to new applications in flexible electronics.
By controlling the concentration of surface oxygen, the researchers could increase the crystal size from a millimeter to a centimeter. Rather than hexagon-shaped and smaller crystals, the addition of the right amount of surface oxygen produced much larger single crystals with multibranched edges, similar to a snowflake. They hope that in the future it will be possible to use this technique to grow meter-length single crystals.