New Hydrogen Research Contract Develops Process
for Screening Storage Materials
“If the idea of a ‘hydrogen economy’ that everyone
is talking about these days is ever to become a reality, then one
of the major technology issues yet to be solved is the area of hydrogen
storage. If hydrogen can be stored safely and efficiently, it
will open up many potential applications for its use. There
are many possible candidate materials that can store hydrogen out
there, and finding the right one is like looking for a needle in a
hay stack! We’ve got a new idea that will speed up the screening
of storage materials and help us move toward the hydrogen economy
goal much quicker.”
With those words, FSEC’s Hydrogen Research Director Ali Raissi
described the goal of the center’s new contract to develop a
novel high throughput material screening apparatus for a wide range
of hydrogen sorbing compounds. Funded by the Navy and Defense
Logistics Agency, the $375,000 contract will enable FSEC researchers
to demonstrate the proof-of-concept rapid materials characterization
for identifying superior hydrogen storage compounds -- speeding the
pace of the discovery by several orders of magnitude.
Hydrogen storage compounds are special materials that can reversibly
absorb hydrogen at preferably low, near-ambient conditions. By varying
the pressure and/or temperature of these materials it is possible
to release the hydrogen and use it to generate power in fuel cells
and other devices.
“What this new process simply means,” Raissi explained, “is
that we can take the unique hydrogen sensing tapes that we developed
as part of our ongoing NASA-funded activity and incorporate them into
a specially designed apparatus that allows discovery of new hydrogen
storage materials much quicker than ever before. Storage is
one of the major challenges facing realization of a hydrogen
economy, and this new project will let us develop a unique process
for rapidly screening candidates for hydrogen uptake, cutting the
time now required for screening for hydrogen storage materials from
hours to literally just seconds.”
FSEC researchers have been working on hydrogen storage compounds
for a number of years, looking at their properties such as capacity,
temperature at which hydrogen will be released and so forth. Since
there are a large number of possible material combinations that can
store hydrogen, it is important to be able to screen and test these
materials quickly. Thanks to the support of the Navy, which
is very interested in the use of hydrogen, the project will develop
a new device for testing as many as 100 potential hydrogen storage
materials or more in just a few minutes.
Raissi explained that the current procedure is to take the candidate
materials -- compounds like metal hydrides and others -- and examine
them one at a time, a process that is very time-consuming.
An important part of the new contract will be for FSEC to be able
to measure the amount of hydrogen released for up to 100 solid adsorbents
simultaneously at a wide range of temperatures and pressures. The
work will involve close collaboration with colleagues at the Naval
Research Lab to identify and use appropriate hydrogen sorption materials
for the calibration and performance verification of the FSEC-developed
rapid screening apparatus.
|
A 25-mil thick section of FSEC-developed
chemochromic film after exposure to various
quantities
of hydrogen gas. |
FSEC researchers have already developed a sensing membrane that contains
special hydrogen sensing pigments that change color when
exposed to hydrogen gas. “What will make this new
approach work,” Ali explained, “is that we will be able
to simply visually inspect the chemochromic membrane after
each dehydriding test run. The changes in the color of the membrane
will give us a direct reading on the amount of hydrogen release from
the samples.”
It is this ability of the naked eye to view the materials and quickly
determine their hydriding/dehydriding properties that will
spur the research process and allow a large number of hydrogen
storage materials to be screened within minutes. The current
screening techniques are hampered by the time-consuming need
for sequential rather than parallel measurements. Speeding up
the screening process is one more accomplishment in addressing the
hydrogen storage challenge.