Michael
Matthew John TREACY
Home Address: 140
West Courtney Lane, Phone:
(480) 598-9021
Tempe,
Arizona 85284-3911. email: mike_treacy@me.com
Date & Place of
Birth: 13th
October 1954 Londonderry,
N. Ireland
Nationality: Dual
citizenship. United Kingdom; Naturalized United States Citizen
Cambridge
University, St JohnÕs College, U.K.
1980 Ph.D.
(Cavendish Laboratory). Thesis Title: ÒElectron Microscopy of Palladium and
Platinum CatalystsÓ. Supervisor, Dr. A. Howie.
1976 B.A.
Hons. 2.1 Natural Sciences (Theoretical and
Experimental Physics). Dissertation: ÒDynamics of the Earth–Moon SystemÓ.
Supervisor, Prof. A. H. Cook.
St. JohnÕs College, Southsea, U.K.
1973 3 ÔAÕ levels (three
grade A passes), Distinctions in Physics and Mathematics.
1971 10 ÔOÕ levels (six grade 1 passes).
6/2003–present Professor,
Department of Physics
Arizona
State University, AZ, USA
10/1990–11/2002 Senior
Research Scientist
NEC
Research Institute, Inc., Princeton, N.J., USA
9/1984–10/1990 Staff
Physicist Exxon
Research & Engineering Co, Corporate Research, N.J., USA
9/1982–8/1984 Senior
Physicist
Exxon
Chemical Company, Aromatics Technology Division, N.J., USA
4/1981–8/1982 IngŽnieur (Grade II) Centre
National dÕEtudes des TŽlŽcommunications,
Bagneux, Paris
1/1980–3/1981 IBM
World Trade Post–Doctoral Position, IBM
Thomas J. Watson Research Center, Yorktown Heights, N.Y., USA
¥ Co–Organizer
of the Materials Research Society Symposium on ÒMicrostructure and Properties
of CatalystsÓ Editor
Proceedings, Vol. No. 111. (12/1987)
¥ Meeting Chair 1991 Materials
Research Society Fall meeting, with M. Yoo (Oak
Ridge) & J. Phillips (Bell Labs).
¥ Treasurer, Editor, Executive
Committee, 9th International Zeolite Conference, MontrŽal, 6/1992.
¥ Chairman
of the Structure Commission of the International Zeolite Association, (7/2001
– present).
¥ Member of the Council of the
International Zeolite Association (1998–2004).
¥ Member (retired) of the
Steering Committee of the National Center for Electron Microscopy
(1989–1994).
¥ Treasurer, Editor, Executive
Committee, for the 12th International Zeolite Conference, Baltimore, 6/1998.
¥ Meeting Chair of Gordon
Research Conference on ÒZeolites and Layered ClaysÓ 6/2002.
¥ Co-organizer of NSF Workshop
on In-situ Microscopy of the nano-World,
Tempe, AZ, 1/2006.
¥ Organizer of workshop on Design and Synthesis of New Materials,
Santa Barbara, Aug 1-2, 2008.
¥ Personnel
Committee for Department of Physics, Fall 2004 – spring 2006.
¥ Budget
& Policy Committee for Department of Physics, fall 2006 – spring 2009.
¥ Colloquium
Committee for Department of Physics, fall 2003 – present.
¥ Chair
of the Physics Colloquium Committee, spring 2005 – fall 2008.
¥ Director of the Undergraduate Physics
Program at Arizona State University, fall 2004 – present.
Wright
Award 1974. Awarded by St. JohnÕs College Cambridge,
for academic excellence.
Best Biological
Poster at the 1995 Microscopy
Society of America conference (best out of 160).
Barrer Award 1990. Awarded triennially by the Royal Society of Chemistry to a
young scientist under age 36, for distinguished work in the area of zeolites.
Donald
W. Breck Award 1996. Awarded triennially by the International
Zeolite Association for the most significant contribution to molecular sieve
science and technology during that 3-year period – for elucidating fault
structures in FAU/EMT zeolites.
Elected Fellow of
the American Physical Society, Nov 2004, For the development of novel electron
microscopy techniques and applications to advanced materials including
catalysts, zeolites, carbon nanotubes and disordered structures.
Outstanding
Teacher 2006–2007.
Awarded by the Department of Physics at Arizona State University based on
nominations by students and faculty.
Distinguished
Teaching Award 2007–2008
in honor of Zebulon Pearce.
Presented by the College of Liberal Arts and Sciences at Arizona State
University based on nominations by students and faculty.
Nominee for Professor
of the Year at ASU, spring 2009.
Leverhulme Professorship at the University of Oxford, Department
of Materials, UK. Sabbatical leave, Aug 2009 – July 2010.
(1)
June
1998, Invited lecture on ÒThe Basics of Crystal SymmetryÓ at U. Illinois, Dept
of Materials Science, given to graduate students.
(2)
(2001-2004) ÒReach
For The StarsÓ. Astronomy coach for two students at Plainsboro, New Jersey, Middle
School. They competed in the New Jersey qualifying tournament and the
National Science Olympiad in 2002 (came 19th) and 2003 (came 10th).
In 2004, the same team came first, although I did not coach them for that full
year because I had moved to Arizona.
(3)
Fall 2003. PHY132 at ASU. Taught laboratory class on Electricity
& Magnetism. Acting T.A. to John Spence. (24 students)
(4)
Fall 2003. PHY241. Substitute lecturer for Prof. D. J. Smith. 2
lectures. (About 70 students.)
(5)
Spring 2004. PHY241 at ASU. Lecture course. 45«50-minute lectures on Thermodynamics, Optics and Modern Physics.
(72 students.)
(6)
Guest Lecture (75 minutes) for course on Nanomaterials organized
by Profs. T. Picraux and D. J. Smith. Lecture Title
was ÒSynchrotron X-ray and Neutron ScatteringÓ. (About 35 students)
(7)
Fall 2004. PHY241 at ASU. Lecture course. 45«50-minute lectures on
Thermodynamics, Optics and Modern Physics. Did all of the quiz and exam grading
myself. (78 students.)
(8)
ASU Winter School on High Resolution Electron Microscopy. Lecture
on Imaging Theory 1, and lab. classes (Jan 2005).
(About 60 students)
(9)
Spring 2005. PHY241 at ASU. Lecture course. 45«50-minute lectures on Thermodynamics, Optics and Modern Physics.
(71 students.)
(10) Fall 2005
PHY521 at ASU. Classical Mechanics. Taught at the graduate level, based on the
Goldstein textbook. 26«75-minute
lectures. (17 graduate students)
(11) Fall 2005.
PHY241 at ASU. Substitute lecturer for Prof. D. J. Smith. 4 lectures. (About 70
students.)
(12) ASU Winter
School on High Resolution Electron Microscopy. Lecture on Imaging
Theory 1, and lab. classes (Jan
2006). (About 45 students.)
(13) Spring 2006.
PHY241 at ASU. Lecture course. 45«50-minute
lectures on Thermodynamics, Optics and Modern Physics. (68 students.)
(14) Spring 2006,
PHY 541 (Surface Science) at ASU. Guest Lecture on Catalysis. (15 students.)
(15) Fall 2006.
PHY521 at ASU. Classical Mechanics. Taught at the graduate level, based on the
Goldstein textbook. 26«75-minute
lectures. (27 graduate students.)
(16) Fall 2006.
PHY 310 at ASU. Stood in for Professor McCartney to give 3 lectures. (~30
students)
(17) Spring 2007.
PHY241 at ASU. Lecture course. 45«50-minute
lectures on Thermodynamics, Optics and Modern Physics. (72 students.)
(18) Fall 2007.
PHY521 at ASU. Classical and Continuum Mechanics. Taught at the graduate level,
based on the Goldstein textbook. Additional material on fluids and chaos. 26«75-minute lectures. (23 graduate students.)
(19) ASU Winter
School on High Resolution Electron Microscopy. Two lectures on Imaging Theory 1
& II, and (Jan 2008). (About 70 students.)
(20)
Spring 2008. PHY252 at ASU. Lecture and lab course. 26«110-minute lectures on Waves, Fluids, Thermodynamics and Optics.
12«110-minute lab classes. (42
students.)
(21)
Fall 2008, PHY 521 at ASU. Classical and Continuum Mechanics.
Taught at the graduate level, based on the Goldstein textbook. 26«75-minute lectures. (23 graduate students.)
(22)
Spring 2009, PHY 252 at ASU. Lecture and lab course. 26«110-minute lectures on Waves, Fluids, Thermodynamics and Optics.
12«110-minute lab classes. (33
students.)
(23)
Spring
2009, PHY 311 at ASU. Stood in for Prof. Barry Ritchie for 1 lecture.
¥ NSF GOALI
award DMR 97-03906, co-Principal Investigator with J. M. Gibson at U. Illinois,
supporting student Paul Voyles. ÒAtomic Correlations in Disordered Materials
observed using Variable Coherence Transmission Electron MicroscopyÓ. $221,000.
¥ NSF GOALI award DMR 00-74273,
co-Principal Investigator with P. J. Keblinski at
Rensselaer Polytechnic, supporting students R. Kishora-Dash
and Juyin Cheng. ÒStructure of Amorphous Materials by Fluctuation Microscopy
and Atomic-level SimulationÓ. 5/2004 – 5/2008, $240,000.
¥ Argonne National Laboratory
(DOE) AWS-0046, ÒFluctuation X-ray/Optical Microscopy Studies of
disordered nano-scale and micro-scale assembliesÓ, $267,622.
¥ NSF NER award CTS
0508434, co-PI with R. Sharma and P. Rez, ÒNER: Controlled Synthesis of carbon nanotubes
with desired propertiesÓ,
7/1/2005 – 6/30/2006, $100,000.
¥ Petroleum
Research Fund, 46779-AC10. $84,000, ÒZeolite structure prediction, and the identification
of useful synthetic targetsÓ, 8/1/07
– 7/31/09.
¥ NSF MRI $3,277,750 ÒAcquisition of an aberration
corrected high resolution analytical transmission electron microscope for
advanced materials researchÓ, co-PI with R. Carpenter, S. Mahajan,
D. J. Smith, J. C. H. Spence 10/1/2008 – 9/30/2011.
¥ NSF CDI-type I $255,559 ÒCollaborative Research:
CDI-type I: ÒDiscovery and design of new microporous
zeolites.Ó, PI with I. Rivin,
Temple 9/1/2008 – 8/31/2011.
¥ Santa Barbara International
Center for Materials Research (ICMR), $100,000, with Mike OÕKeeffe (ASU), to
run a Summer School and Workshop on Materials Design.
¥ UOP/Honeywell $30,000
unrestricted gift, to build a diffraction pattern database of hypothetical zeolites.
¥ Proposed, and demonstrated, the high-angle annular
detector for STEM Z contrast
My
Ph.D. work was on the development of advanced TEM-based techniques for the
characterization of supported Pt and Pd catalysts. At that time, CreweÕs Z contrast technique seemed ideal for
detecting high atomic number (Z)
elements such as Pt, on low atomic number supports that are typical of
supported catalysts. I demonstrated that diffraction produced strong contrast
that overwhelmed the Z-contrast
effect in crystals. In collaboration with supervisor A. Howie
and L. M. Brown, I showed that upon increasing the annular detector inner
collection angle, diffraction contrast could be suppressed. This work
introduced the high-angle annular detector in Materials Science.
Further, the Z-dependence of the
signal improved to Z2
because atomic screening effects are diminished. (This seemingly simple
experiment required time and some considerable ingenuity to overcome design
limitations in the early STEM instruments.) In later work, I demonstrated
single Pt atom sensitivity in zeolites, with the
channels clearly imaged giving us an indication as to the likely location of Pt
atoms in the framework. I also showed that high angle annular dark field
intensities could be used to estimate sub-nanometer particle sizes reliably.
The high-angle annular detector is now a standard tool in (S)TEM
studies of materials.
¥ Identified a new
deactivation mechanism in Pt/K-zeolite L aromatization catalysts
My STEM Z
contrast studies of Pt particles in the one-dimensional channels of zeolite L
revealed that Pt particles agglomerate slowly with reaction time. The particles
remain sufficiently small so that over 90% of the Pt atoms reside on particle
surfaces. However, double-blockages in the zeolite channels effectively entomb
a significant channel volume, and the loss of active Pt can be severe. I
proposed a length-loading criterion for maintaining activity. The
criterion is simple: there should not be enough Pt per channel to form two or
more significant blockages. This hypothesis was confirmed when zeolite L
supports with shorter channel lengths, but identical Pt loading, were tested.
For proprietary reasons this work (1982–1985), which represents the
culmination of my early Z contrast
work, was published only in 1999. I won the prestigious Barrer
Award (awarded triennially by the British Zeolite Association) in 1990 for part
of this work.
¥ Demonstrated the dominant role of elastic relaxation in TEM
images of composition-modulated films
My work at CNET in Paris was on spinodal decomposition of InGaAsP
semi-conductors, which are used as photodiodes in fiber-optic
telecommunications. Electron microscopy revealed pronounced quasi-periodic
image contrasts that were traditionally ascribed to local composition
fluctuations. In collaboration with J. M. Gibson and A. Howie,
I showed that the contrast is primarily due to the bending of lattice planes
near surfaces, which is induced by relaxation of stresses arising from the
modulation in unit cell dimensions as the composition changes. Such bending
produces strong diffraction contrasts. I derived equations for the bending,
which remain useful for studies of strain modulation in all types of modulated
thin films, from superlattices to ferroelectrics.
This work also showed how to convert TEM lattice spacings into a local
composition, allowing for the relaxed tetragonal distortions and their
dependence on thickness.
¥ Unraveled the structure
of chiral zeolite beta
Synthetic zeolite beta
was first reported by Mobil
in the mid 1960s. Its structure remained a mystery for over 20 years. The
presence of planar faults in the sub-micron sized crystallites made it
essentially impossible to solve the structure by conventional
structure-refining methods. Using TEM to extract structure projections and the
symmetry elements, in collaboration with J. M. Newsam,
I showed that the structure comprises intimately intergrown
right- and left-handed variants of a chiral tetragonal framework. (It later
transpired that J. B. Higgins at Mobil had solved the structure 3 years earlier
by model-building, but had not been allowed to
publish.) The zeolite beta structure is important because it is a 3-dimensional
12-ring framework, with helical channels running along the c-axis. Nobody has
synthesized the pure right- or left-handed forms yet, but such a pure
end-member structure may have applications in chiral separations. The methods I
used, and the tools I created, in this work have been used by other researchers
for structure determinations of other intergrown
zeolite families.
¥ Invented recursion algorithm for computing
diffraction from faulted crystals – DIFFaX
During
the course of the zeolite beta work, I developed a recursion method of
computing powder x-ray diffraction patterns in the presence of planar faults.
This tool helped provide the crucial evidence supporting our model of zeolite
beta. I am the primary author of the computer program DIFFaX, which has now become a
standard tool for simulation of diffraction in planar-faulted crystals, and has
been used widely by other researchers for over 20 years. I have used it
successfully in many projects to identify fault patterns in layered crystal
systems. The Fortran DIFFaX source
code, with manual, is in the public domain.
¥ Characterization of stacking
fault patterns in faujasitic zeolites using TEM and DIFFaX simulations
The
tools I developed for studying zeolite beta where applied to studying the
faulting distributions in the various faujasite-related synthetic zeolites,
ranging from pure cubic FAU framework to the pure hexagonal EMT framework.
Using TEM and DIFFaX, I showed that the faulting in
these materials is correlated. Using the strain relaxation model, I showed that
the strains associated with the stacking faults were reduced when faults were
clustered. I won the prestigious Breck Award (awarded
triennially by the International Zeolite Association) in 1996 for this work.
¥ Combinatorial computer method for
enumerating zeolite frameworks
In collaboration with
computer scientists K. Randall and S. Rao, I built a
computer program to carry out a combinatorial search over every possible crystallographic
graph in order to extract all of the 4-connected periodic zeolitic graphs. For
one unique tetrahedral atom there are over 6,400 4-connected graphs, of which
about 200 refine to regular tetrahedral topology. This work took over 10 years
to bring to fruition, and discovered many new theoretical zeolite frameworks,
and revealed some interesting idiosyncrasies in the International Tables for Crystallography. This work is
collaboration with I. Rivin and Martin Foster. This is an active research area.
¥ Fluctuation
Microscopy: A powerful TEM technique for revealing medium-range order in
amorphous materials.
In collaboration with J.
M. Gibson, we have shown that statistical analysis of the speckle observed in
dark-field images of amorphous materials provides a measure of medium-range
order. We have called this new analytical TEM technique Fluctuation Microscopy. We have used fluctuation microscopy to
solve some long-standing problems in amorphous materials. We have shown that
as-deposited amorphous germanium and silicon films contain paracrystalline
regions. On annealing below the recrystallization temperature, Ge (but not Si) transforms to the lower-energy continuous
random network. We have also shown that amorphous hydrogenated silicon (a-Si:H) undergoes a significant
structural re-arrangement on light-soaking – an observation that may lead
to an improved understanding of the Staebler-Wronski
effect which currently limits the efficiency of a-Si:H
solar cells. Fluctuation microscopy is now being used in several laboratories.
This work remains active and has been extended to scanning x-ray microscopy of
disordered nanomaterials (with I. McNulty and J. M.
Gibson at Argonne), and also to scanning optical microscopy (student D. Kumar). This is an active research area.
¥ SchlŠfli
cluster methods for modeling amorphous tetrahedral models.
Borrowing
from my work on zeolite topologies, I have developed a simple topological tool
for investigating medium-range order in models of amorphous tetrahedral
semiconductors. SchlŠfli clusters are compact
topological descriptors of the local connectivity around each atom. (It later
emerged that they are similar to the earlier Òlocal clusterÓ concept of L. W.
Hobbs et al.) I have proposed that the diamond SchlŠfli
cluster is the minimum atomic configuration that can be called Òtopologically
cubicÓ. Searching for such clusters is a fast effective tool for detecting
medium range order in models of amorphous semiconductors.
¥ In-situ TEM observations of
domain switching in ferroelectric thin films.
In
collaboration with A. Krishnan, we made in-situ TEM observations of domain wall
motion in thin single crystal ferroelectric materials under applied electric
fields. I designed, and had built, a special TEM specimen holder that can heat,
apply electric fields and shine light onto a sample. Our observations showed
that domain walls do not move as rigid membranes. Instead, we proposed that
domain walls move by allowing charged ripples to propagate along them. We
developed a simple Landau-Ginsburg Free energy argument showing that ripples
have a reduced barrier to switching. Ripples enable wall motion by a mechanism
analogous to that for dislocation motion in crystal slip. We also showed that
some domain walls are locked under certain electric field directions,
representing an inherent contribution to ferroelectric fatigue and imprint.
¥ Developed
an effective dynamical diffraction Bloch wave explanation for the anomalous
transmission of light through thin hole arrays.
When
light is shone on a thin metallic film, which has a periodic array of
sub-optical wavelength diameter holes drilled through it, anomalously high
intensities are transmitted at certain wavelengths. That is, more light gets
through than would be expected from the projected hole
area. The current popular explanation is that surface plasmons
ÒguideÓ the light through the holes. I have developed an alternative dynamical
diffraction Bloch wave theory that completely explains the anomalous
transmission, and does so without resorting to special pleading about surface plasmons. The theory is fully general for 3-dimensional
periodic gratings, and unlike the other theories, makes no simplifications or
approximations to MaxwellÕs equations.
¥ Exploited
thermal vibrations to measure YoungÕs modulus of carbon nanotubes
Long carbon nanotubes
that extend over holes in a TEM support film cannot be imaged clearly at their
tips because of vibrations. The vibration amplitude at the tip can be several
nanometers, and this blurring motion is normally a problem for high-resolution
TEM studies. I realized that the vibrations are elastically relaxed phonons and
represent heat motion. By measuring the r.m.s. vibration amplitude as a function of temperature, I
estimated the YoungÕs modulus to be ~1.8 teraPascal,
which makes carbon nanotubes the stiffest known material. Later, in
collaboration with T. W. Ebbesen, A. Krishnan and E. DuJardin, we applied this method to single-walled nanotubes
and obtained values of ~1.2 TPa, which we believe are
closer to the correct value. In collaboration with P. Yianilos,
I developed a hidden-parameter-inferencing
technique to improve and quantify the accuracy of the method. This unique
application of TEM attracted international attention, including highlights in Physics Today, C&E News, New Scientist,
Bild der Wissenschaft etcÉ
¥ Designability of graphitic carbon cones.
In
collaboration with Ebbesen, Krishnan and DuJardin, we described in the journal Nature a special carbon black sample that comprised a high density
of graphitic disks and cones. Our TEM analysis confirmed that the five
topologically-allowed conical forms all occur in this sample, but with a
preponderance of the 60¡ cone-angle variety. I explained this distribution with
a simple model of graphitization. I pointed out that there are many more ways
to circumscribe carbon rings around the tip of a cone than there are ways to
imbed the same rings in planar graphite. For topologically flexible seeds,
graphitic cones are more ÒdesignableÓ than planar graphite. With an assumed
seed distribution, the model explains the observed cone distribution –
highlighting the role of entropy in the formation of curved graphitic structures.
¥ Primary
author of the ÒCollection of Simulated XRD Powder Patterns For ZeolitesÓ.
The
Structure Commission of the International Zeolite
Association maintains an up-to-date website describing the approved zeolite frameworks. Periodically, the Commission published
updated handbooks describing zeolite frameworks and
their diffraction patterns. I wrote a computer program that automates the
production of the book ÒCollection of Simulated XRD Powder Patterns For Zeolites.Ó This was not a trivial task, but was an
enjoyable, instructive and satisfying challenge. The program is due to be used
next in 2012-2013 for the sixth edition.
¥ Mathematical tools for
characterizing zeolite frameworks.
In
part-collaboration with I. Rivin and Martin Foster, I
have developed a number of public-domain computational tools for characterizing
zeolite frameworks. TOTOPOL is used to explore zeolite
structural details and topologies. It is my primary tool when examining new
framework proposals to the IZA Structure Commission. DelaneysDonkey is a whimsically-named code that executes a Delaunay
triangulation of zeolite frameworks to identify the
largest included sphere and the largest freespheres
in a framework. This gives a good idea of the porosity characteristics. I wrote
both computer programs.
¥ Flexibility
of zeolite frameworks.
In collaboration with Asel Sartbaeva, Stephen Wells and Mike Thorpe at ASU, we showed
that almost all of the known zeolites exhibit a
flexibility window when modeled as Ideal Zeolite
Frameworks. This important result provides a key test of hypothetical
frameworks; if they lack flexibility, the likelihood of them being realized in
nature is diminished. The composition of the framework is important, as the
presence of different-sized tetrahedra can promote or
diminish flexibility. An active research topic at present is the exploration of
the nullspace represented by the flexibility window,
with a view to computing the configurational entropy
of the framework. An open question at present is whether or not the entropic
density is a maximum when the framework density is minimum. Intuition says Òyes,Ó
but we are exploring this using advanced computational tools
(collaboration with Vitaliy Kapko
and Colby Dawson.) This is an active research area.