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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 | N O V E M B E R / D E C E M B E R 2 0 1 5

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The first direct measurement of

resistance to bending in a nanoscale

membrane was made by scientists from

the University of Chicago, Peking Univer-

sity, the Weizmann Institute of Science,

and the Department of Energy’s (DOE)

Argonne National Laboratory. Their find-

ings give researchers a new and simpli-

fied method to measure nanomaterials’

resistance to bending and stretching,

opening new possibilities for creating

nanosized objects andmachines by con-

trolling and tailoring that resistance.

“Researchers around the world are

seeking ways to manipulate ultrathin

nanomaterials into stable 3D objects.

The challenge is how to make a 2D film

into a 3D shape when the film is so thin

and flexible. You need something stiffer

than you would expect. It turns out that

many nanomembranes may already

possess that property,” explains Hein-

rich Jaeger of the University of Chicago.

“We were surprised to find that

the gold nanomembrane was over 100

times more resistant to bending than

we predicted, based on standard elastic-

ity theory and our experience with thin

sheets such as paper,” says Xiao-Min Lin,

who fabricated the gold nanoparticles in

specialized facilities at the Center for Na-

noscale Materials at Argonne.

Critical to the team’s discovery is

a new method for creating gold mem-

branes that roll themselves into nano-

sized scrolls plus a new technique for

measuring the scroll’s resistance to

bending. The nanoscrolls were self-as-

sembled by suspending a fluid con-

taining gold nanoparticles on a carbon

screen. As the fluid dried, it left a gold

membrane suspended likeanano-drum-

head across the screen’s circular holes.

As the membranes continued to dry

and tighten, one edge pulled loose from

Scientists discovered how to measure the resistance of a nanomembrane to both

bending and stretching by rolling it into a tube andmeasuring the tube’s bending

resistance along its length. Courtesy of ANL.



National Science Foundation

will provide a total of $81 million over five years to support 16 sites and a coordi-

nating office as part of a new

National Nanotechnology Coordinated Infrastructure

(NNCI).The NNCI sites provide

researchers from academia, government, and industry access to university facilities with fabrication and characteri-

zation tools, instrumentation, and expertise within nanoscale science, engineering, and technology.

the screen, and the membrane sponta-

neously rolled up to form a hollow tube.

Because the measurement is based only

on elasticity theory and the tube’s geom-

etry, it should have general applicability

across a wide range of materials and size

scales, from nano and microtubules to

macroscopic objects.



Anodized aluminum oxide (AAO)

nanosensor arrays are now being used

to electrochemically detect lead levels

in a rapid and inexpensive manner, say

researchers at Zetanostics Inc., Santa

Fe, N.M. The simple electrochemical

approach uses a potentiostat and does

not require reagents, spectroscopy, or

colorimetry. While the U.S. Environ-

mental Protection Agency limits lead

in public drinking water systems to

15 parts per billion, the AAO nanosen-

sor method can reliably test to two

parts per billion. Sandia National Lab-

oratories, Albuquerque, N.M., filed a

patent on this technology nine years

ago, but the process was cost prohib-

itive and complex. Scientists at Zeta-

nostics worked with Sandia’s team for

two years to make the technology com-

mercially viable. Arrays can be used to

test water at homes and schools, com-

mercial buildings and plants, aquifers,

storage tanks, and more. In addition,

the technology can be applied to test

for arsenic, hexavalent chromium, cop-

per, and other pollutants.

For more in-

formation: Shobhan Paul, 310.721.0977,