Issue 16/2016 - New technology accelerates the production of single crystal graphene films

New technology improves the production speed
of single crystal graphene film Chinese scientists have increased the speed of graphene film production by 150 times
through the adjustment and improvement of chemical vapor deposition (CVD).
The new research lays the foundation
for the large-scale application of graphene.

Although the demand for graphene is huge, its preparation speed is slow, and the utilization rate has been hovering around 25%, which has become one of
the bottlenecks restricting its entry into practical applications.
At present, the method of preparing high-quality graphene, except for tape peeling method, silicon carbide or metal surface epitaxial growth method, is mainly chemical vapor deposition method
.
However, the production of single crystal graphene film by CVD technology still takes a long time, and the preparation of a centimeter square single crystal graphene film takes at least one day, which is very slow
.

In the new study, researchers at Peking University and the Hong Kong Polytechnic University have developed a new technique that accelerates the process from 0.
4 microns per second to 60 microns per second, a 150-fold
increase in speed.
The trick is to add a little oxygen
directly to the copper foil participating in the reaction.
The researchers say that the continuous supply of oxygen increases the growth rate
of graphene.
They confirmed this by electron spectroscopy, but measurements showed that oxygen, although released, was small
in total.
The researchers explain that this may have something to do
with the trapping effect of the very small space between the oxide substrate and the copper foil, which improves the efficiency of oxygen utilization.
In experiments, the researchers were able to produce 0.
3 mm of single-crystal graphene
in just 5 seconds.