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Basic Energy Sciences Directorate
CFN, Chemistry, Condensed Matter Physics & Materials Science
Jim Misewich
Associate Laboratory Director for Basic Energy Sciences
BNL is at the center
of a large, vibrant research community in the Northeast, offering access to
world-class user facilities and scientists in a highly collaborative and
interdisciplinary environment. The Basic Energy Sciences (BES) Directorate
has strengths in strongly
correlated and complex systems, photon and neutron science, chemical
dynamics, and interface phenomena and catalysis. New investments are being
made in nanoscience, materials synthesis, solar energy, soft matter and
biomaterials with the underlying goal of having impact on the nation’s
energy security. A BES Complex is envisioned that integrates our science and
facilities, and is coupled to university and industrial partners, and to
other major research facilities at BNL.
The Basic Energy Sciences Directorate consists of three components:
the condensed matter physics and materials science department (CMPMSD), the
chemistry department (CHEM), and the Center for Functional Nanomaterials
(CFN). The CFN, like all the DOE nanoscience research centers, serves both
as a user facility and as a science department. The
BES directorate and all its components are strongly aligned with the BNL
energy strategy, and in particular, with the complex materials, catalysis
science, and solar energy themes of the BNL energy strategy. CMPMSD is
primarily aligned with the complex materials theme of the BNL energy
strategy, and in particular the superconductivity part of that theme. CMPMSD
also contributes to the solar energy theme through work on photovoltaic
materials and thermoelectric materials. The Chemistry department is
primarily aligned with the catalysis theme of the BNL energy strategy but
also makes major contributes to the solar energy theme, particularly in
solar fuels. The CFN plays a significant role in the lab energy strategy as
one of the pillars, along with NSLS, NSLS-II, and New York Blue, providing a
platform for understanding the role of nanostructured materials for energy
applications. In addition to the broad role that the CFN plays nationally as
a major user facility providing the tools and expertise for nanoscience
research, the CFN also plays a major role in the BES directorate’s energy
science strategy. The science themes of the CFN (nanocatalysis/interface
science, electronic nanomaterials, and soft/bio nanomaterials) are aligned
with the BNL energy strategy themes in catalysis and solar energy.
In order to provide meaningful scientific impact, Brookhaven Basic Energy
Sciences directorate investigators have focused on science themes that are
directly connected to DOE-BES priority research directions and grand
challenges in catalysis science, correlated electron and complex materials
science, and nanomaterials science. In each of these areas significant
advances were demonstrated in FY2008. Brookhaven catalysis programs advanced
our understanding of heterogeneous catalysis, photocatalysis, and
electrocatalysis related to energy conversion processes for clean and
renewable energy research. Brookhaven materials scientists discovered
unusual aspects of the nature of superconductivity in correlated electron
and complex materials. Advances in the synthesis and assembly of functional
nanomaterials were demonstrated by Brookhaven researchers.
Complex Materials: As
exemplified by the ternary and quaternary perovskite oxides, the advent of
structurally and chemically complex materials has led to the discovery of
new classes of materials that often exhibit the most extreme physical
properties, including high temperature superconductivity in the cuprate
family. The latter discovery and the observation of strong electronic
correlations in these materials, has stimulated an enormous research effort.
However, the complexity of these materials and elusive mechanism for high
temperature superconductivity remains a grand challenge in materials
science. The importance of superconductivity to the nation’s energy strategy
is illustrated in the DOE-Basic Energy Science Report from the Workshop on
Superconductivity. In addition, in a recent DOE-BESAC report, understanding
and controlling the remarkable emergent properties of complex and correlated
materials was identified as one of the five grand challenges for science and
the imagination. The complex materials theme is the major theme of the CMPMS
department, which is already playing an internationally recognized leading
role in correlated electron materials.
Catalysis Science: The DOE-BES Basic Research Needs workshop on Catalysis has identified catalysis
science as one of the key research directions that can secure national
energy needs and address global warming, which are perhaps the two most
scientifically challenging problems of this century. Reduction of the energy
consumption needed for chemical transformations, increase in the efficiency
of energy production, conversion and use from fossil fuels, and mitigation
of the environmental impact of these processes will all depend on the
development of future catalysts. Furthermore innovative catalysts are needed
for the supply of renewable, sustainable, clean fuels from sunlight to
fulfill the daunting projected global energy demand. The catalysis science
theme in the BES directorate is carried by two units: the Chemistry
department, which has widely recognized leadership in catalysis particularly
in nanocatalysts for electrochemistry, and the new Center for Functional
Nanomaterials (CFN), which has already developed unique new tools for the
in-situ study of catalysis. Much of the Brookhaven role in catalysis can be
associated with redox chemistry at interfaces. This includes themes such as
fuel cell electrocatalysis, carbon reduction reactions, solar-induced water
splitting, and catalysis for the hydrogen economy.
Solar Energy: The most
abundant renewable and carbon-neutral source of energy is solar. The DOE-BES
Workshop report on Solar Energy Utilization points out that more energy
strikes the surface of the earth in one hour than is utilized by the planet
in an entire year. However, the fuel and electricity generated through solar
technology represents only a very small fraction of the energy consumed by
society. Two of the three research opportunities identified by the DOE-BES
Solar Energy Utilization report are solar electricity and solar fuels. The
Brookhaven Solar Energy strategy is focused on these two areas and the BES
directorate has nascent programs contributing to our solar energy theme.
Although the solar energy theme is the newest and least developed of the
directorate themes, the emergence of the CFN, NSLS-II, and the New York Blue
computing facility provides Brookhaven with an outstanding and complete set
of complementary tools to synthesize, probe, and understand nanostructured
materials and interfaces with unprecedented precision and resolution. In
concert with our core research programs we have an opportunity to develop a
significant solar energy program to provide new materials and understanding
of nanostructured forms of matter for the optimization of charge transport,
energy flow, and chemical reactivity.
- Oleg Gang has led a team from BNL’s
CFN and Biology departments that have achieved what some see as the "holy
grail" of nanoscience. Researchers have for the first time used DNA to guide
the creation of three-dimensional (3D), ordered, crystalline structures of
nanoparticles (particles with dimensions measured in billionths of a meter).
The ability to engineer such 3-D structures is essential to producing
functional materials that take advantage of the unique properties that may
exist at the nanoscale - for example, improved catalytic activity and new
optical properties. This work was published in Nature 451 (7178), 549-552,
January 31 2008 and was the cover article.
- A group from the CFN led by Peter Sutter has
demonstrated that crystalline graphene can grow epitaxially on ruthenium (Ru)
in a controlled, layer-by-layer fashion, thus opening the door to rational
graphene synthesis on transition-metal templates for applications in
electronic, sensing and catalysis. The primary method for preparing graphene
is micro-mechanical cleavage of graphite, but scaling up that method for
applications is difficult. Epitaxial growth has been an attractive
alternative, but until now achieving large graphene domains with uniform
thickness and electronically unaffected by the substrate has been a
challenge. Sutter’s group has shown experimentally that large graphene
domains can be prepared on Ru and that, although the first graphene layer
interacts strongly with the metal substrate, the second layer retains the
inherent structure of graphene. This work was published in Nature Materials,
7 (5), 406-411 May 2008.
- J.C. Seamus Davis from BNL and Cornell, in collaboration with
colleagues at Cornell University, Tokyo University, the University of
California, Berkeley, and the University of Colorado, have uncovered the
first experimental evidence for why the transition temperature of
high-temperature superconductors - the temperature at which these materials
carry electrical current with no resistance - cannot simply be elevated by
increasing the electrons' binding energy. The research demonstrates how, as
electron-pair binding energy increases, the electrons' tendency to get
caught in a quantum mechanical "traffic jam" overwhelms the interactions
needed for the material to act as a superconductor - a freely flowing fluid
of electron pairs. This work was published in Nature 454 (7208), 1072-1078,
Aug 28 2008.
- Guangyong Xu and colleagues from BNL, Stony Brook, Johns Hopkins University
and the Center for Neutron Research, NIST, report a study of the phase
instability induced by the polar nanoregions (PNR) in a relaxor system.
Relaxor ferroelectrics are a special class of material that exhibit an
enormous electromechanical response and are easily polarized with an
external field. The PNRs are specific to relaxor ferroelectrics and play a
key role in governing their dielectric properties. Xu and colleagues have
shown through neutron inelastic scattering experiments that the PNRs can
also significantly affect the structural properties of the relaxor
ferroelectric. They find a strong interaction between the PNRs and the
propagation of acoustic phonons. They suggest that a phase instability
induced by this PNR-photon interaction may contribute to the ultrahigh
piezoelectric response of this and related relaxor ferroelectric materials.
This work was published in Nature Materials 7 (7), 562-566, July 2008.
- BNL scientists advanced their understanding of several next-generation
catalysts for generation of pure hydrogen for fuel cells and other
applications, using a novel model nanocatalyst. The scientists had
previously shown through in situ characterization by x-ray methods at
NSLS that the active form of the advanced catalysts consist of gold or
copper nanoparticles on ceria nanoparticle supports. However, the roles of
the various catalyst components have been unclear. In new work, Jan Hrbek,
Jose Rodriguez and Ping Liu of the BNL Chemistry Department and the CFN,
together with researchers from the University of Venezuela used an ‘inverse’
model nanocatalyst consisting of nanoparticles of ceria supported on a gold
surface to demonstrate clearly that both metal and oxide components are
important to the catalytic function, and provided computational evidence
that the components facilitate separate parts of the reaction sequence, with
a key final step occurring at the interface between the metal and oxide
components. These insights offer clues to improve the performance of
catalysts for hydrogen production. The work was published in Science, 318
(5857): 1757-1760 Dec 14 2007.
- An important element of the BNL catalysis effort to elucidate the structure
and function of energy conversion catalytic processes is the development and
study of realistic model nanocatalysts. In 2008, Mike White, Ping Liu and
collaborators advanced the use of a nanocluster beam as a source of model
nanocatalysts. They generated ionized nanoclusters – groups of 10 to 100
atoms – of molybdenum sulfide by magnetron sputtering, selected a single
nanocluster species by ion-beam mass selection, and soft-landed the clusters
on gold surfaces for reactivity characterization. They demonstrated that
isolated nanocluster reactivity properties were maintained and reactivity
could be studied over a wide range of temperatures and explained using DFT
electronic structure methods. The molybdenum sulfide nanoclusters are
models of materials used in hydrodesulfurization, a process that removes
sulfur from natural gas and petroleum products to reduce pollution. The
advance demonstrates promise of size-selected cluster beams for detailed
studies and improved understanding of multi-component catalysts in a range
of energy conversion chemistry. The work was published in Journal of
Physical Chemistry C, 223 (30): 11495-11506 July 31 2008.
- BNL research to demonstrate routes for conversion of solar energy to fuels
aim for a viable artificial photosynthetic route to oxidize water to oxygen
and simultaneously to form an energy carrying fuel by reducing protons to H2,
or by reducing carbon dioxide to CO, formate or methanol. In two advances
published in FY2008, teams of Chemistry department scientists (Etsuko
Fujita, Jim Muckerman, Dmitry Polyansky and Diane Cabelli), in collaboration
with Japanese investigators from the Institute for Molecular Science,
elucidated the mechanism of improved catalysts that can speed such chemical
reactions. This research demonstrated a novel mechanism of a new efficient
water oxidation catalyst (Inorganic Chemistry, 47 (6): 1787-1802 Mar
172008), and investigated a new photocatalyst with promise to reduce C=O
groups (ketones) to alcohols, and thus potential for reduction of carbon
dioxide to alcohol (Inorganic Chemistry, 47 (1): 3958-3968 May 19 2008).
Both efforts combined photochemistry and pulse radiolysis methods to
elucidate mechanism of catalysts based on inorganic complexes.
- In a search for effective fuel cell electrocatalysts for the difficult
oxygen reduction reaction that can reduce or eliminate the use of expensive
platinum, BNL researchers pursued both new alloy nanoparticles, and
continued their promising strategy of core-shell nanoparticles by depositing
platinum monolayers on nanoparticles cores to increase the platinum weighted
electrocatalytic activity. Pd3Fe showed activity similar to Pt
nanoparticles, and was even more promising when coated with a monolayer of
Pt, showing activity 5x higher per unit weight of platinum than a commercial
platinum electrocatalyst. The researchers also showed some promise for
completely eliminating noble metal in the core by using Pt monolayers on an
oxide core using Niobium oxide. This latter case showed overall platinum
weighted activity similar to that of the commercial platinum catalyst, and
opens a new opportunity to explore acid-stable conductive oxides as more
stable supports for nanoparticles electrocatalysts. Work by Radoslav Adzic,
Miomir Vukmirovic, Kotaro Sasaki, and Ping Liu (Zeitschrift fuer
Physikalische Chemie-International Journal of Research in Physical Chemistry
& Chemical Physics, 221 (9-10): 1175-1190 2007; Physical Chemistry Chemical
Physics, 10 (1): 159-167 2008).
 Last Modified: January 30, 2009
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