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A D V A N C E D M A T E R I A L S & P R O C E S S E S | M A R C H 2 0 1 5
1 6 NANOTECHNOLOGY
BRIEFS
Graphene Energy Storage Devices Corp. signed a research agreement with the
Research Foundation of Stony Brook University (SBU), N.Y, to develop new super-
capacitor designs for energy storage. The goal is to develop low-cost, integrated
ultra-high voltage supercapacitor units using a high-rate reel-to-reel process. SBU
will design the electrode and electrolyte formulation, while the Graphene ESD team
will work on device assembly and testing. ,
Treated carbon-60 molecules can recover valuable metals from liquids, including
water and potential pollutants. In testing various metals, charge and ionic radius
were found to influence howmetals bind to hydroxylated buckyballs. Courtesy of
Jeff Fitlow/Rice University.
BUCKYBALLS BIND TO METAL
Andrew Barron, Rice University,
Houston, discovered that carbon-60
fullerenes (buckyballs) that have under-
gone hydroxylation can aggregate into
pearl-like strings as they bind to and
separate metals from solutions. Barron
says treated buckyballs handle metals
with different charges in unexpected
ways, which could make it possible to
pull specific metals from complex fluids
while ignoring others.
A series of experiments explored
the relative binding ability of fullerenols
to a range of metals. Fullerenols com-
bine with a dozen metals, turning them
into solid cross-linked polymers. In or-
der of effectiveness, these include zinc,
cobalt, manganese, nickel, lanthanum,
neodymium, cadmium, copper, silver,
calcium, iron, and aluminum. Barron
says fullerenols act as chelate agents,
which determine how ions and mole-
cules bind with metal ions. For more
information: Andrew Barron,
, .
PREDICTING PROPERTIES OF
METAMATERIALS
Scientists with the DOE’s Lawrence
Berkeley National Laboratory, Calif., and
the University of California, Berkeley
show that it is possible to predict the
nonlinear optical properties of metama-
terials. Confocal microscopy was used
Confocal microscopy confirms that
the nonlinear optical properties of
metamaterials can be predicted using
a theory about light passing through
nanostructures.
to observe the second harmonic gener-
ation from metamaterial arrays whose
geometry was gradually shifted from a
symmetric bar-shape to an asymmet-
ric U-shape. Second harmonic light is
a nonlinear optical property in which
photons with the same frequency inter-
act with a nonlinear material to produce
new photons at twice the energy and
half the wavelength of the originals.
“Our results show that nonlinear
scattering theory can be a valuable tool
in the design of nonlinear metamateri-
als not only for second-order, but also
higher order, nonlinear optical respons-
es over a broad range of wavelengths,”
says Xiang Zhang, director of Berke-
ley Lab’s Materials Sciences Division.
“We’re now using these experimental
and theoretical techniques to explore
other nonlinear processes in metama-
terials, such as parametric amplifica-
tion and entangled photon generation.”
For more information: Xiang Zhang,
.
GRAPHENE 3D LAB
INC., CALVERTON, N.Y.,
COMMISSIONED AN
INDUSTRIAL SCALE
THERMOPLASTIC EXTRUDER
LINE TO BE USED IN THE
PRODUCTION OF CONDUCTIVE
GRAPHENE FILAMENT. THE
NEW EQUIPMENT CAN
PRODUCE 10 KG PER HOUR
OF 3D PRINTER FILAMENT.