Growth and
transfer of 2-D material such as hexagonal boron nitride and graphene was
performed by a
team that included Yijing Stehle of Oak Ridge National Laboratory.
(December 1, 2015) A
new era of electronics and even quantum devices could be ushered in with the
fabrication of a virtually perfect single layer of “white graphene,” according
to researchers at the Department of Energy’s Oak Ridge National Laboratory.
The material, technically known as hexagonal boron nitride,
features better transparency than its sister, graphene, is chemically inert, or
non-reactive, and atomically smooth. It also features high mechanical strength
and thermal conductivity. Unlike graphene, however, it is an insulator instead
of a conductor of electricity, making it useful as a substrate and the
foundation for the electronics in cell phones, laptops, tablets and many other
devices.
“Imagine batteries, capacitors, solar cells, video screens
and fuel cells as thin as a piece of paper,” said ORNL’s Yijing Stehle,
postdoctoral associate and lead author of a paper published in Chemistry of
Materials. She and colleagues are also working on a graphene hexagonal boron
2-D capacitor and fuel cell prototype that are not only “super thin” but also
transparent.
With their recipe for white graphene, ORNL researchers hope
to unleash the full potential of graphene, which has not delivered performance
consistent with its theoretical value. With white graphene as a substrate,
researchers believe they can help solve the problem while further reducing the
thickness and increasing the flexibility of electronic devices.
While graphene, which is stronger and stiffer than carbon
fiber, is a promising material for data transfer devices, graphene on a white
graphene substrate features several thousand times higher electron mobility
than graphene on other substrates. That feature could enable data transfers
that are much faster than what is available today. “Imagine your message being
sent thousands of times faster,” Stehle said.
Stehle noted that this work is especially significant
because it takes the material beyond theory. A recent theoretical study
(http://news.rice.edu/2015/07/15/white-graphene-structures-can-take-the-heat/)
led by Rice University, for instance, proposed the use of white graphene to
cool electronics. Stehle and colleagues have made high-quality layers of
hexagonal boron nitride they believe can be cost-effectively scaled up to large
production volumes.