FY 2014 - 2015
Annual Report
Multi-Scale Technologies Institute
July 2015
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MuSTI Overview for 1 July 2014 – 30 June 2015
Multi-scale technologies are those that bring together functional elements to form systems where the
relative size of components within the system spans from the nano through the micro and into the macro
domain. The systems-focus of MuSTI emphasizes the challenges associated with integrating
technologies that have relative feature sizes that are orders of magnitude apart, and operating
characteristics that are size dependent. The Multi-Scale Technologies Institute (MuSTI) became
operational near the end of 2005 and is currently authorized until December 2015. The number of
proposals submitted by MuSTI affiliates continues to flourish. Compared to 2013-2014, the number of
different submitting PI and Co-PIs increased 14%, the number of different agencies to which proposals
were submitted was up 47%, the number of new and incremental awards was up 39%, and the amount
of those awards was up 57%.
Among the awards is an NSF MRI for a scanning transmission electron microscope that, as instrumented,
will be perhaps unique in the world. It is anticipated that during 2015-16, MuSTI will make a significant
contribution to help facilitize this instrument. This was anticipated and is the primary reason that MuSTI
expenditures during 2014-2015 were lower than in past years. The infrastructure improvements that
MuSTI funding has implemented in the past, continues to be utilized by students and faculty in research
across campus.
During the 2014-2015 reporting period:


Proposals submitted during the period
Number of different PIs and Co-PIs
Number of different departments/units of PI/Co-PIs
Number of different agencies submitted to
Approximate total request
Number of PhD funding years requested
Number of new and incremental awards during the period
Total funding of new and incremental awards
47
24
6
22
$14,944,611
91
25
$ 4,823,363
MuSTI had a fiscal year beginning IRAD balance of $175,973 and an ending balance of $181,838 with
IRAD revenue of $70,989 and expenditures of $65,124. Expenditures supported:





$ 2,161
$ 24,524
$ 5,429
$ 24,316
$ 5,168
graduate student support
equipment, including musti.q on Superior cluster (expended this period)
travel to potential sponsors and conferences
cost share and non-mandatory transfers, including nanotechnology course support
supplies and services
Craig Friedrich, Director
Paul Bergstrom, Associate Director for Fabrication and Facilities
John Jaszczak, Associate Director for Education and Outreach
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Computing Infrastructure Support
During the prior FY, MuSTI supported the acquisition of 64 additional processors via four compute
nodes for Superior. This queue (MuSTI.q) is used to provide highest submission priority to MuSTI
affiliates and when not fully utilized is open for other users, and brings the overall compute capacity to
nearly 31 TFLOPS.
During the current reporting period, MuSTI.q was used for 1,876 simulations spanning nearly 400,000
hours of CPU time.
At a very nominal fee of $0.10 per CPU core per hour, this usage amounts to $38,183 for this year
alone. This can be treated as the level of funds that MuSTI researchers would have had to spend on
external computing services (e.g., Amazon/Google Cloud Computing services) if these nodes were not
available for use. The one-time cost of acquiring these nodes was approximately $24,000.
Research Highlights
During the reporting period there were 47 new proposals submitted and 25 new or incremental awards.
The research of MuSTI affiliates continues to be diverse spanning many dimensional scales. In this
report two such examples are detailed. In these cases, the research spans from the geologic scale to
the atomic scale.
Modeling Shock Waves from Explosive Volcanic Eruptions
Dr. Ezequiel Medici, Mechanical Engineering – Engineering Mechanics
Dr. Jeffrey Allen, Mechanical Engineering – Engineering Mechanics
Dr. Gregory Waite, Geological and Mining Engineering and Science
The following is condensed from a funding proposal submitted by Dr. Ezequiel Medici. We are
investigating the dynamic interaction between expanding gas, water content (in liquid or vapor states),
and solid particles in a supersonic jet. The coupling between the state and content of the water, and the
particle size and concentration will modify jet development and evolution by changing how energy is
dissipated. However these effects have not been thoroughly investigated yet. In volcanology, unlike other
applications where gas jets are present, a mixture of relatively high water content and a high
concentration of small solid particles are present in the expanding jet. The understanding of these
coupled effects is critical to understanding volcanic jet dynamics and the subsequent formation and
expansion of the volcanic plume and pyroclastic flows.
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The work has an important impact through both the potential for application of new knowledge gained
about jets and through the interdisciplinary education and training of students. The novel interdisciplinary
nature of the work is also highlighted by the collaboration between geophysics and mechanical
engineering researchers, which we expect will lead to additional research projects in the future. This type
of interdisciplinary work generates new ideas and has the potential to lead to transformative new
understanding in volcanology.
The development of an improved understanding of jet characteristics has the promise of a direct impact
on volcanic eruption modeling. During a violent eruption, a shock wave is formed followed by a jet and
eventually the ash plume. The understanding of some of the main parameters controlling the jet
characteristics will contribute not only to the overall understanding of the eruption dynamics but also the
formation of the ash cloud and pyroclastic flow. The study of the volcanic jet can also elucidate and
contribute to identifying potential threats and hazard zones, such as the historical eruption of Mount St.
Helens.
Figure 1: Left: Generic volcanic jet schematic used to model the eruption of Mount St. Helens in May 1980 showing its
distinctive regions [1]. Right: Supersonic jet obtained at the Atmospheric Shock Facility at Michigan Tech under an
initial pressure condition of 750 PSI (5.17 MPa).
Explosive volcanoes have historically presented a harmful destructive natural force. In addition to the
immediate damage inflicted by the eruption on the surrounding areas, large ash clouds associated with
eruptions present problems to crops, air traffic, human health (air quality), and tourism, among others.
The ash cloud generated by explosive eruptions can reach many kilometers in height and several
hundreds of kilometers distance, presenting a serious problem not only for the local region but also an
immediate threat for the air traffic routes near the volcano. The sudden release of a compressed mixture
of vapor, liquid, and solid particles from the conduit into the atmosphere can generate a shock wave
immediately followed by a supersonic jet. The volcanic vent, acting as a nozzle, allows for an expansion
of the mixture into a complex supersonic jet flow pattern. Though it is hard to visualize under ambient
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conditions, a fully developed jet structure will have a Mach disk - a standing shock wave - enclosed by a
rarefaction wave as shown Figure 1. Above the jet region, the hot mixture will expand and depressurize
in the atmosphere and an ash plume or pyroclastic flow will develop. The entrainment and heating of air
is critical to the development of the buoyant plume and determines the eventual plume height as well as
whether the column collapses to form pyroclastic density currents.
During a violent eruption, a shock wave may be generated that is immediately followed by the formation
of a supersonic jet. The overpressurized multiphase mixture being ejected begins to expand and
accelerate. Oblique shock waves and rarefaction waves are generated at the edge of the crater. The
oblique shock waves, inclined with respect to the flow axis, intersect forming a structure called a Mach
disk or Mach diamond. This pattern repeats until the jet decelerates into subsonic flow. From the edge of
the crater there is also a rarefaction wave formed around the jet. The complex structure and the relative
sizes and distance from the vent are function of the eruption properties such as overpressure, discharge
time, fluid properties, and vent shape. For instance, the distance between the jet Mach disk and the
source of the jet, x, for an ideal, dry pure gas can be approximated by:
where D is the diameter of the jet injection, Ps is the pressure at source of the jet and Pa is the atmospheric
pressure. Figure 2 is a sequence of images demonstrating the evolution of a sudden release of
compressed nitrogen from the Atmospheric Shock Facility, beginning with the initial ballistic shock and
ending with a fully-developed supersonic jet. This type of volcanic jet model has been used to study jet
formations and the decompression wave occurring inside the exiting volcanic conduit.
a) 100 µs
b) 200 µs
c) 400 µs
d) 1366.66 µs
Figure 2: Left to Right: a) Initial shock wave, b) expanding shock wave and oblique shock waves formation on the jet
at the edge of the exit of the shock tube, c) Rarefaction wave and oblique shock waves intersection and formation of
the Mach disk, d) fully developed Mach disk. Image sequence of the jet generation taken at 30,000 fps using dry
compressed nitrogen at 750 psi. Field of view is approximately 9.15 by 9.15 cm. Reference time is taken from the instant
that the shock wave exits the shock tube.
While the image sequence presented in Figure 2 might seem trivial, it provides a reference background
study for the non-trivial cases such as jets having a mixture of components. As an example, Figure 3
shows an image sequence of similar jets (same initial discharge energy) with low concentrations of
particles. These tests were achieved by adding a “loading” chamber before the gas exit of the shock tube
to hold the particles prior to the discharge. On these images, the typical jet structures (especially the
Mach disk) are no longer easy to recognize. This opens the question whether the Mach disk exists at all,
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as well as bringing attention to the interaction between particles. In particular, we note that in our
preliminary tests with particles of various sizes and under a small range of conditions, direct particleparticle collisions have not been observed. Instead, particles commonly interacted with nearby particles
through their Mach cones.
a) 6 mm
b) 3 mm
c) 1 mm
Figure 3: Left to Right: Dry jets of nitrogen containing spherical particles of different sizes ranging from 6 to 1 mm in
diameter. Field of view is approximately 9.15 by 9.15 cm.
We have made initial measurements using Michigan Tech’s Atmospheric Shock Facility, developed with
the support of NSF Award EAR125013. The results obtained with compressed nitrogen are in good
agreement with theoretical and experimental shock behavior despite the fact that these shocks are not a
point source detonation and are considered “weak” with maximum Mach number of ~2. Figure 4 illustrates
the general shock tube design. The gas exit of the shock tube is threaded to accommodate loading
chambers of different volumes, 51.4, 154.4, and 300 cm3 respectively, in which to place solid particles.
The apparatus is fully instrumented with a high-speed imaging system and a pressure transducer to
visualize and record the pressure signature of the discharge. The high-speed camera used in the
experiments is capable of a maximum of 250,000 frames per second (fps) with reduced field of view. For
most of the experiments performed, a time resolution of 30,000 to 75,000 fps was used, which gives
256x256 pixel spatial resolution (i.e. Figures 2 and 3). If a higher temporal resolution is needed (higher
fps) techniques such as double exposure (this could be especially convenient for particle tracking) can
be used to maintain a desirable pixel resolution.
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Figure 4: Schematic diagram of Split-Hopkinson pressure bar test gun modified for use a ballistic shock generator. The
driver section is filled with nitrogen at various test pressures. Green, blue, and red lines indicate the gas passage
during filling, triggering, and expansion, respectively.
We have conducted preliminary tests of particles in supersonic jets with spherical particles of three
different diameters: 1, 3, and 6 mm. While the 1 and 3 mm particles were glass, the 6 mm were plastic.
These particles were placed inside the jet by filling the largest loading chamber (300 cm3) with them. By
observing the video imaging of the expanding gas-particle mixture, as shown in Figure 3, it was possible
to track the particle position versus time as well as the Mach cones evolving around them as they
accelerated. These tests were performed at different initial energy as dictated by the shock tube driver
pressures of 250, 500, and 750 PSI.
The key objective of the research is to simulate the supersonic jet emanating from an explosive volcano
and to use the experimental results to better understand the effects of water content (vapor and liquid
state), particle size, and particle concentration on the jet structure and behavior. The main objectives of
this project are to:
 identify how different particle sizes will interact with the jet,
 analyze the effect of particle concentration on the jet structure and the formation of complex flow
patterns such us clustering and fingering,
 test the effect of liquid water drops in the jet dynamics,
 determine the impact of the vapor content on the jet dynamics.
Specific questions to be addressed in order to achieve the main objectives are:
 Will particle size and concentration change the jet structure by originating complex flows such us
clustering and fingering? If so, which are the particle size and concentration ratio at which these
effects become dominant?
 When particles of different sizes are mixed inside the jet, will they tend to separate, generating
regions of high concentrations of particles of the same size?
 How much momentum, as manifested through the slip velocity, is transferred from the jet to water
droplet or particles?
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


Will water drops vaporize under the effect of the different pressure regions of the jet? Is there a
critical water droplet size?
How much will the water vapor (stoichiometry) inside the jet mixture, in ranges typically found in
a volcanic eruption, change the jet dynamics? Will vapor condense into water into water drops?
What are the overall implications of the presence of solid particles, water drops, and water vapor
inside the jet to volcanic eruptions? Will any of these significantly affect the evolution of the ash
plume or the formation of pyroclastic flows?
Reference
[1] Kieffer, S. W., "Factors governing the structure of volcanic jets." Explosive volcanism: inception,
evolution, and hazards. National Academy, Washington (1984): 143-157.
MRI: Acquisition of a High Resolution Transmission Electron Microscope for
In Situ Microscopy Research and Education
Dr. Reza Shahbazian Yassar, Mechanical Engineering – Engineering Mechanics
Dr. Stephen Hackney, Materials Science and Engineering
Dr. Yoke Khin Yap, Physics
Dr. Tolou Shokuhfar, Mechanical Engineering – Engineering Mechanics
Dr. Claudio Mazzoleni, Physics
Dr. Craig Friedrich, Mechanical Engineering – Engineering Mechanics
The following is condensed from a funded proposal by the PIs. The modern era of materials science
involves the correlation of atomic level structure and chemistry with macroscopic properties. The
structure/chemistry foundations of materials performance continue to expand with our abilities to engineer
materials at the nanoscale level. Also critical is the education of students with the ability to integrate
materials structure with materials chemistry. This skillset will enable them to perform research on the
design of materials for high performance tasks and to address a variety of functional materials challenges.
Materials research and education at the point of discovery require an electron microscope that is capable
of simultaneously measuring material structure and chemistry at the sub-nanometer scale.
This project received funding from the National Science Foundation for the acquisition of a FEI Titan field
emission transmission electron microscope (TEM), equipped with scanning capabilities (STEM), and the
necessary detectors and spectrometers for high-resolution Z-contrast imaging in conjunction with
electron energy-loss spectroscopy (EELS), energy dispersive X-ray spectroscopy (EDS) spectrum
imaging, and full remote control. This instrument will substantially enhance the interdisciplinary research
and educational efforts carried out by faculty and students at Michigan Tech and beyond. The current
research covers several fields that are national priorities such as energy storage, nanomaterials
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synthesis, climate change, biomineralization, photovoltaics, graphene, and electronics. Breakthrough
advances in these fields require the ability of imaging and mapping materials’ structure and composition
under different environmental stimuli at the sub-nanometer scale. An extension of the equipment
capabilities utilizing in situ studies allows electric, thermal, mechanical, and chemical (gas and liquid)
stimulation of materials, as a method to test critical hypotheses regarding structure, chemistry, and
performance relationships. The following are snapshots of the research that is enabled by this
acquisition.
In Situ Atomic-Resolution Electrochemistry for Rechargeable Batteries: PI: R. Shahbazian-Yassar,
Mechanical Engineering-Engineering Mechanics
Atomic resolution and spectrum imaging of elemental distribution at the electrode-electrolyte interface of
rechargeable batteries are major milestones that we aim to achieve. We have conducted several in situ
electrochemical studies of Si nanowires and recently were successful in lithiation studies (in situ) of SnO2.
In this approach, we use ionic liquids as the electrolyte media and Li-metal as the anode (Fig. 1). The
electrical biasing of the in situ holder will be conducted with an
electrochemical workstation for the charge and discharge
operations.
Fig 1. (Top) In situ electrochemistry setup for Li-ion battery testing
is shown. Ionic liquids (ILs) are used as electrolyte. (Bottom)
Results show a nanowire in the in situ electrochemical setup with
ILs.
Figure 2 shows preliminary results on the lithiation of SnO2
nanowires. The data show that atomic resolution can be
recorded successfully during the lithiation process. In particular,
imaging revealed the presence of lithiated strips at the reaction
front and data confirmed that the strips are enriched with Li
indicating that the long-range lithiation is the primary step in full
lithiation of SnO2 nanowires. In later stages of lithiation, the
formation of Sn crystalline particles and their lithiation through
LixSn was directly observed. We plan to perform spectrum
imaging to study the changes in the distribution of Li atoms.
Fig. 2. Preliminary in situ TEM electrochemistry results. Atomic
resolution HAADF images were obtained for pristine SnO2 and in
situ lithiated SnO2 by sending PhD students to Chicago (~9 hours
driving) to use the STEM facility at UIC.
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In Situ Electromechanical Probing of Boron Nitride-Carbon Hetrojunctions: PI: Yoke Khin Yap,
Department of Physics
Boron (B), Carbon (C), and Nitrogen (N) are the smallest atoms that could form the strongest covalent
materials on earth. We have established capability in growing high-quality BN nanotubes (BNNTs). The
EELS capability of the instrument is an important tool for us to study the stoichiometry of BN composition
and evaluate the compositional quality of the as-grown BNNTs. Figure 3 shows an example of HRTEM
and EELS work that was conducted by the co-PI’s student at Argonne National Laboratory. The distinct
K-edge peaks at 188 and 401 eV identifies that the composition of the nanotube is boron and nitrogen.
Using the STEM, we will study the electron energy-loss near edge structure (ELNES), which arises from
the energy distribution of the empty electronic states above the Fermi level, and can provide information
on the local density of empty states, the oxidation state, bonding and local coordination. We will utilize
the ELNES as ‘‘fingerprints’’ for different bonding configurations of a particular species to extract bonding
maps from the ELNES information. The B–K ELNES is considered because of the high ionization cross
section of this edge (so that spectra with a short acquisition time—100ms per spectrum—can be
recorded) and the high sensitivity of these ELNES to the chemical environment.
Fig 3. Preliminary data obtained at
DOE-ORNL show HRTEM, energy
filtered mapping, and EELS of
BNNTs.
Recently, we have created two new nanostructures with intriguing BN-C nanojunctions including
graphene-BNNT junctions. We are interested to understand the stability of the atomic structure of BN-C
junctions under electrical, mechanical, and thermal stability using our in situ holders (Fig. 4). The EELS
spectrum imaging will be used to map B and N atoms in the nanotubes at high temperatures to better
understand the chemical redistribution induced by Joule heating. Theoretically, BN-C junctions are
energetically very stable with atomically abrupt interfaces. It is predicted these junctions are applicable
for Schottky devices, ferromagnetic quantum dots, spintronic valves, and tunable photonic/optical
devices. It is interesting to correlate these physical properties to the composition, and band structures of
these junctions. The high-resolution imaging and EELS mapping capabilities are highly beneficial for our
work owing to the small differences of atomic size and short bonding lengths between B-C-N atoms.
Fig. 4. Results showing mechanical deformation of a single BN
nanotube. The current instrument does not allow us to study the
changes in EELS signal under mechanical loading or EELS
mapping of B and N elements during Joule heating.
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In Situ Microscopy of Mixing State of Atmospheric Aerosol Nanoparticles: PI: Claudio. Mazzoleni,
Department of Physics, Atmospheric Sciences Program
The primary research focus of Mazzoleni's group is to study optical, physical and compositional properties
of atmospheric aerosols. Aerosols affect the Earth's atmospheric radiative transfer by interacting directly
with solar and terrestrial radiation, and indirectly by affecting the properties and lifecycle of clouds through
complex feedbacks. Still today, the detailed understanding of the role of aerosols in atmospheric
processes constitutes one of the single largest key gaps in our knowledge that hinders our ability to
accurately predict future climate changes.
Fig. 5. Preliminary HAADF image and EDS maps (using a
STEM instrument at UI-Chicago on samples collected by
Mazzoleni’s group) of a mineral dust particle, where sodium
chloride is detected at the lower right. The presence of NaCl
on mineral dust mimic the case of desert particles transported
over the ocean that gets coated/mixed with sea salt. We plan
to map the elemental composition of particles under heating,
gas relevant to several atmospheric processes.
Natural and anthropogenic aerosol particles are compositionally and morphologically very complex,
showing inhomogeneous distributions of C, H, O and other elements such as Na, Cl, K, P and S in
amorphous and crystalline forms (Fig. 5). The mixing state of atmospheric aerosols and their detailed
composition affect their interaction with the solar radiation and their physical and chemical interaction
with the surrounding environment, including their ability to act as cloud condensation or ice nuclei.
Quantifying the mixing state, morphology and internal and surface composition of single particles – with
sensitivity to specific atomic composition and chemical bonding – is therefore critical to enhance our
understanding of atmospheric processes and to develop physically and chemically-based aerosol
parameterizations for numerical climate models. The instrument will be used to investigate single particle
properties on statistically significant ensembles, relevant to different atmospheric processes and aerosol
sources. The instrument will be used to: (I) perform EELS spectrum imaging and EDS mapping with
atomic resolution to study the details of aerosol mixing, morphology and composition (Fig. 5); (II) study
aerosols under gaseous, liquid, and thermal stimuli to understand aerosol oxidation, water-induced
processes, and aerosol compounds’ volatility. In particular, we will take advantage of STEM imaging, the
gas and high-temperature holder, and the tomography capabilities to understand (1) at what
temperatures specific compounds volatilize? (2) What coating thickness corresponds to a given volatility
temperature? (3) Are there changes in the morphological structure or surface properties of carbonaceous
particles during different environmental stimuli? (4) How homogenous is the mixing of different
compounds within a single particle? We will take advantage of the large and unique archive of
atmospheric aerosol samples collected by Mazzoleni’s group during several field and laboratory studies
(e.g.; from Pico Mountain Observatory, Azores in the North Atlantic, India, a chamber study at PNNL,
and others). Currently, several students in Mazzoleni’s group routinely use the available electron
microscopy capabilities on campus; the new microscope allows a significant gain in our ability to perform
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detailed new analysis and discoveries to advance the field that will not be possible to fully realize within
existing national facility availabilities.
In Situ STEM Lithiation Studies of Novel Cathode Materials for Li-ion Batteries: PI: Steve
Hackney, Materials Science and Engineering
Fig.
6.
Preliminary results
showing a HRTEM image of a
0.7Li2MnO3·0.3Li4Mn5O12
composite
structure.
Closepacked (001) layered planes
aligned parallel to (111) spinel
planes.
Hackney’s work has contributed to the TEM experimentation,
crystallographic interpretation and concept development in the
discovery of novel, nanostructured oxides for secondary (as an
Argonne National Laboratory team member) and primary (as a battery
manufacturer team member) Li-ion positive electrodes. Using STEM
as a primary tool, Hackney’s group has assisted in the development
of several newly-engineered oxide materials that rely on nanometerscale crystal structure improvements in composite electrodes. Our
work in cooperation with a large battery manufacturer has led to a new
commercial product for primary Li ion batteries while work with ANL
has led to materials for secondary battery electrodes with a 20%
improvement in discharge capacity. We have studied lithiummanganese oxides containing structurally integrated domains of
layered and spinel phases (Fig. 6), represented in two-component
notation as xLi2MnO3•(1-x)Li1+yMn2-yO4 (0<x<1, 0y0.33). The
electrochemical
data
clearly
demonstrate
that
the
0.7Li2MnO30.3Li4Mn5O12(400) electrode structure provides a
rechargeable capacity that is significantly higher than the capacities
provided by the single-component Li2MnO3 and spinel reference
electrodes.
A causality between the defects and the electrochemical properties of novel cathode materials will be
examined using the in situ electrochemical cell for direct observation of Li interaction with the layer defects
using high resolution EELS Li spectrum imaging and EDS mapping (Fig. 7). The possibility of fade
mechanism due to transition metal clustering/Li site clustering and Li transport channel blocking due to
the associated strain will be investigated. The high resolution ADF imaging capability of the microscope
provides the ability to study such an effect through the intelligent use of the camera length. As the camera
length increases, the ADF image switches from Z-contrast to de-channeling (defect) contrast. In this
manner, the Z-contrast/de-channel contrast correlation for the initial high capacity material may be
compared with the same correlation for the faded material. This would be the first attempt at a direct
correlation between local composition variations and localized Li transport channel defects and could act
as part of the proof or disproof of the clustering/defect hypothesis.
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Fig. 7. Preliminary data obtained using a STEM
instrument in Chicago showing high resolution
STEM-EDS maps of P, O, Ti, and Fe atoms in
LiTiFePO4 nanoparticles. Ti segregation is
evident. (Sample courtesy of Argonne National
Laboratory).
In Situ High-Resolution Imaging of Mineralization Processes in Liquids: PI Tolou Shokuhfar,
Mechanical Engineering-Engineering Mechanics
Dr. Shokuhfar’s laboratory is focused on Liquid-STEM imaging of metal oxides that are biocompatible
and exist within the human body. We recently published our first paper on this topic in Advanced
Materials. We also have prior experience with in-situ TEM studies of metal oxide nanomaterials under
the application of external loads. To conduct studies on the structure and dynamics of nanomaterials in
liquid, we use both Si-MEMS designed chips and
graphene cells. Figure 8 shows Shokuhfar’s in situ liquid
cell holder that was acquired from Protochips.
Fig. 8. In situ liquid flow holder utilizes a Si-MEMS chip
with Si3N4 windows and allows the transport of liquid into
TEM. The liquid cell holder is compatible with JEM-2100F.
We will study the real-time mineralization of
nanoparticles using ferritin structures. Ferritin is a
suitable choice for in situ STEM studies because its high
iron content core gives high Z-contrast imaging signal.
In fact each ferritin complex can store about 4500 iron (Fe3+) ions. The iron core is surrounded by an
organic shell consisting of 24 subunits and exists within cells of the human body. Ferritin plays an
important role in iron transport and in protecting the body from iron-ion toxicity. By calibrating contrast
levels in the HAADF images and using quantitative EELS, we aim to estimate the iron content in a ferritin
core, and to produce a three dimensional reconstruction of the average core morphology. The valence
and oxygen coordination of the iron in the mineral cores will be also monitored as a function of electron
influence (e/nm2) by quantifying the ELNES of the Fe L2,3-ionisation edge measured using EELS. Fe L2,3-
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core edge EEL spectra will be
acquired by using the spectrum
imaging technique. A defocused
electron probe will be used to scan a
small area (effectively the defocused
probe being moved very little). Using
STEM-HAADF imaging, we also will
investigate the relationship between
the crystallographic orientations of
core subunits that deliver iron to the
central cavity. Understanding the
underlying dynamic mechanisms
behind the mineralization of the
ferritin core in Liquid-STEM could
open up new means for introducing
protein cages for nanomaterials
synthesis. The co-PI’s preliminary
data demonstrates the successful
real time imaging of ferritin protein
using our liquid holder inside a STEM
as shown in Fig. 9
Fig. 9. Preliminary data demonstrate the successful HAADF imaging
of ferritin nano-cages immersed in a liquid cell inside a STEM
instrument.
Research Activities Enabled for Senior Personnel & External Users
Michigan Tech Senior
Personnel
In addition to the in situ microscopy work above, the instrument capabilities will have great impact for
other faculty members and external users. More than 15 faculty members from 7 departments at Michigan
Tech and several external users expressed great interest to use the STEM for their research projects.
External users are from major industries (3), universities (3), and federal lab (1). The additional Michigan
Tech users are shown in the table below.
PI’s Name
Dept/Institution/Indus
try
Microscope Needs
Durdu Guney
Joshua Pearce
Julia King
Craig Friedrich
STEM-HAADF on TiO2-SrTiO3 surfaces
HAADF/EELS of InGaN NWs for photovoltaics
In situ SPM testing of graphene composites
EDS and EELS studies of TiO2 NTs
Bruce Lee
Patricia Heiden
Lyon King
Electrical Eng
Materials Science Eng
Chemical Eng
Mechanical Eng
Mechanical&Materials
Eng
Biomedical Eng
Chemistry Dept
Mechanical Eng
John Jaszczak
Physics Dept
Educational collaboration: Nano Certificate
Chang K Choi
Mechanical Eng
In situ STEM for nanoparticle-liquid films
Greg Odegard
High resolution imaging of nanocomposites
HAADF of hydrogel nanocomposites
HRTEM and EELS of nanoparticles
In situ emission studies on ionic liquids
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Impact on Research and Training Infrastructure
The PIs believe that given the level of complexity associated with this instrument, the major educational
impact will be for our undergraduate, graduate, and surrounding community college students. One of the
most effective mechanisms that has already been in place at Michigan Tech for the past decade is the
requirement of MY5250-Basic TEM course for students who wish to use the existing TEM. In this course,
the students receive in class lectures as well as laboratory hands-on experiences on the current TEM.
With the addition of the new FEI Titan STEM, our students will be exposed for the first time to hands-on
laboratory activities related to STEM, HAADF, EELS, and EDS mapping.
New Educational Initiative: To prepare students for their in-depth microscopy research needs that
require the FEI Titan, we will develop a new online course tentatively titled “MY5990-Advanced TEM”
that will provide in-depth discussion on microscopy concepts (in situ microscopy, aberration correction,
EELS, HAADF imaging etc.). The on-campus students will have weekly hands-on laboratory experiences
to practice high resolution imaging, STEM-HAADF imaging, and EELS/EDS. The off-campus students
will obtain remote access to practice such capabilities under the supervision of the PI and the new
microscopy staff.
In addition, a major undergraduate program at Michigan Tech (minor Certificate in Nanotechnology,
which began in fall 2005) will immediately benefit from this new microscopy capability. In this program,
the undergraduate students (from all departments across MTU) will gain a multidisciplinary exposure to
nanotech courses, including MY5990-Advanced TEM course where the capabilities of the STEM will be
taught in details. The integration of this new course with Certificate in Nanotechnology program allows
the wide exposure of this new instrumentation to any undergraduate student with interests in
nanotechnology or nanoscience.
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