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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 2 EMERGING TECHNOLOGY
NSF AWARDS $56 MILLION
FOR MATERIALS RESEARCH
In February, the National Science
Foundation (NSF) announced awards
worth $56million in funding for 12Mate-
rials Research Science and Engineering
Centers (MRSECs). NSF’s newest MRSEC
at Columbia University will have two
interdisciplinary research groups (IRGs)
attempting to build higher dimension-
al materials from lower dimensional
structures with unprecedented control.
One of the groups will study how 2D
materials interact to create novel geom-
etries and structures for potential use in
electronic devices. The other group will
work on establishing a new type of pe-
riodic table by using molecular clusters
to assemble materials with exception-
al electronic and magnetic properties.
BRIEFS
For the first time, University of Chicago scientists experimentally observed a phenome-
non in ultracold, three-atommolecules predicted by Russian theoretical physicist Vitaly
Efimov in 1970. In this quantum state, called geometric scaling, the triatomic
molecules fit inside one another like an infinitely large set of Russian nesting
dolls. The illustration shows the sizes of the triatomic, lithium-cesium
molecules at a fraction of a degree above absolute zero.
Courtesy of Shih-Kuang Tung/Cheng Chin.
Columbia will lead the MRSEC and part-
ner with City College of New York, Har-
vard University, Barnard College, the
University of the Virgin Islands, Brookha-
ven National Laboratory, IBM, and Du-
Pont. The partners will work together to
develop educational outreach activities
for nearby K-12 schools.
The other 11 awards, made to exist-
ing MRSECs, also represent cutting-edge
materials science and engineering, and
in most cases, the centers will take on
newmaterials research and focus on ed-
ucation. Awardees include Brandeis Uni-
versity, University of Chicago, University
of Colorado at Boulder, Harvard Univer-
sity, University of Minnesota, Massachu-
setts Institute of Technology, University
of Nebraska, New York University, The
Ohio State University, Penn State Univer-
sity, and Princeton University. .
SILICON NANOFIBERS BOOST
BATTERY PERFORMANCE
Researchers at the University of
California, Riverside’s Bourns College of
Engineering developed a novel paper-
like material for lithium-ion batteries
that could boost performance several
times over. The material, composed of
spongey silicon nanofibers more than
100 times thinner than human hair,
could be used in batteries for elec-
tric vehicles and personal electronics.
Nanofibers were produced using elec-
trospinning, where up to 40,000 V is
applied between a rotating drum and
nozzle that emits a solution composed
mainly of tetraethyl orthosilicate.
The nanofibers are then exposed
to magnesium vapor to produce the
spongelike silicon fiber structure. This
technology also solves a problem that
has plagued freestanding, or binderless,
electrodes for years—scalability. Free-
standing materials grown using chem-
ical vapor deposition, such as carbon
nanotubes or silicon nanowires, can
only be produced in very small quanti-
ties (micrograms). However, the team
was able to manufacture several grams
of silicon nanofibers at a time, even at
the lab scale. For more information: Mihri
Ozkan, 951.827.2900, ,
.
An MRSEC team fromHarvard ex-
amined the formation of biofilms
in B. subtilis, a type of rod-shaped
bacteria often found in soil, which
can cause agricultural damage
and corrosion. Courtesy of Hera
Vlamakis, Harvard University
Medical School.
Scanning electron microscope images of
(a) SiO2 nanofibers after drying, (b) SiO 2
nanofibers under high magnification,
(c) silicon nanofibers after etching, and
(d) silicon nanofibers under high magnifi-
cation. Courtesy of UC Riverside.