INOR 1 Robust surface-anchored UiO-66-based metal-organic-framework films on polymer fibers ...

673 Pages·2017·24.84 MB·English

by  Joshua Blair

INOR 1
Robust surface-anchored UiO-66-based metal-organic-framework films on
polymer fibers for rapid hydrolysis of chemical agents
Gregory Parsons, [email protected], Junjie Zhao, Dennis T. Lee, Heather F. Barton.
North Carolina State University, Raleigh, North Carolina, United States
MOFs in common powder form are difficult to integrate into functional devices and
composite materials. Surface-immobilized MOF thin films on flexible polymer fibers can
potentially overcome the inherent limitation of powders, and simplify deployment and
expand utilization for gas filtration, separation, catalysis and biomedical applications.
Our group has developed a platform technology that addresses the critical challenges
for MOF integration on fibers. Using atomic layer deposition (ALD), we formed well-
defined conformal nanoscale metal oxides on fiber substrates that promote
heterogeneous MOF nucleation and growth. We found that ALD TiO enables the
2
solvothermal formation of highly conformal Zr-based UiO-66, UiO-66-NH and UiO-67
2
MOF thin films on polypropylene and nylon fibers. Growth uniformity, MOF mass
loading, surface adhesion, robustness and overall BET surface were all significantly
enhanced with ALD nucleation layers. We find the approach is broadly extendable to
other MOF systems, including HKUST-1, MOF-74, MIL-96 and others. HKUST-1
functionalized polypropylene nonwoven fabrics exhibit large adsorption capacity for
toxic industrial chemicals including NH and H S. UiO MOF thin films on ALD-coated
3 2
nylon-6 nanofibers were applied for catalytic degradation of chemical warfare agents.
Half-lives of CWA simulant DMNP are less than 8 min with UiO-66-NH and UiO-67 thin
2
films on nylon nanofibers, while half-lives of GD are all less than 4 min with our MOF-
nanofiber catalysts. These results all demonstrate the excellent adsorption and catalytic
performance of our MOF-functionalized fibers. Studies describing the basic nucleation
reactions during MOF nucleation will be described, including the role of metal oxide
composition on MOF nucleation behavior.
UiO-66-NH MOF grown on nylon nanofibers using ALD TiO nucleation layers. The MOFs on
2 2
fibers retain the surface area and catalytic functionality of similar MOF powders. The fiber mat
shows uniform coverage, and the mat retains the mechanical integrity of the starting fiber
material.
INOR 2
Metal organic framework’s acid dissociation constants as a robust descriptor of
their morphology and reactivity: Applications to hydrolysis of warfare agents
Mohammad R. Momeni, [email protected], Christopher J. Cramer. Department
of Chemistry, Supercomputing Institute and Chemical Theory Center, University of
Minnesota, Minneapolis, Minnesota, United States
Understanding electronic properties of metal bonded O-H moieties in metal organic
frameworks (MOFs) is of prominent importance in gaining insights into their
topologies/morphologies as well as their reactivities. In this study, accurate quantum
mechanical methods are performed using both periodic/cluster models and
explicit/implicit solvation models for computing acid dissociation constants (pK s) of a
a
wide variety of water stable/soluble Zr MOFs. Effects of replacing Zr with Ce as well as
Th and U on the computed pK s are thoroughly investigated. A combination of different
a
functionals are used to determine impact of the employed methodology on the accuracy
of both the periodic and the cluster data. Moreover, possible linear correlations between
acidic properties of these O-H groups and the effectiveness of the MOF in capturing and
detoxification of nerve agents will be explored and discussed thoroughly. Results of this
study are central in appreciating the role of O-H groups in ever expanding applications
of these 3D crystalline materials.
INOR 3
Reaction of the chemical warfare agent simulant, DMMP(g), with zirconium (IV)
MOFs: An ultrahigh-vacuum and DFT study
Guanyu Wang1, [email protected], Conor H. Sharp1, Anna Plonka2, Qi Wang2, Anatoly
Frenkel2, Weiwei Guo3, Craig L. Hill3, Cecilia Smith1, James Kollar4, Diego Troya1, John
R. Morris1. (1) Department of Chemistry, Virginia Tech, Blacksburg, Virginia, United
States (2) Department of Materials Science and Chemical Engineering, Stony Brook
University, Stony Brook, New York, United States (3) Department of Chemistry, Emory
University, Atlanta, Georgia, United States (4) Department of Chemistry and
Biochemistry, Kennesaw State University, Kennesaw, Georgia, United States
The mechanism and kinetics of interactions between dimethyl methylphosphonate
(DMMP), a key chemical warfare agent (CWA) simulant, and Zr -based metal organic
6
frameworks (MOF) have been investigated with in situ infrared spectroscopy (IR), X-ray
photoelectron spectroscopy (XPS), and DFT calculations. DMMP was found to adsorb
molecularly to UiO-66 through the formation of hydrogen bonds between the phosphoryl
oxygen and the free hydroxyl groups associated with Zr nodes on the surface of
6
crystallites and not within the bulk MOF structure. Unlike UiO-66, the infrared spectra for
UiO-67 and MOF-808, recorded during DMMP exposure, suggest that uptake occurs
through both physisorption and chemisorption. DFT calculations, used to guide the IR
band assignments and to help interpret the XPS features, suggest that uptake is driven
by nucleophilic addition of a surface OH group to DMMP with subsequent elimination of
a methoxy substituent to form strongly bound methyl methylphosphonic acid (MMPA).
The rates of product formation suggest that the reactions are diffusion limited.
Importantly, the final products were found to inhibit further reactions within the MOFs,
thereby limiting any catalytic turnover for this gas-MOF reaction.
Time-resolved IR spectra of MOF-808 upon DMMP exposure at room temperature (298 K)
INOR 4
Molecular modeling insights into the adsorption and degradation of hazardous
chemical warfare agents by metal-organic frameworks
Jacob Harvey2, [email protected], Dorina F. Sava Gallis1, Jeffery A. Greathouse2. (1)
MS 1415, Sandia National Laboratories, Albuquerque, New Mexico, United States (2)
Geochemistry, Sandia National Laboratories, Albuquerque, New Mexico, United States
Organophosphates represent a highly toxic class of chemicals and include chemical
warfare agents (CWAs) such as sarin, soman, and HD. The degradation chemistry of
these compounds is well known in aqueous, corrosive environments, but less is known
about their behavior in non-aqueous, non-corrosive environments. Metal-organic
frameworks (MOFs) represent a promising class of heterogeneous catalysts for the
decontamination of CWAs because of their intrinsically high surface area and tunability
of their pore chemistry and size. More importantly, their ease of processability allows
them to be used in a non-aqueous solution. Inspired by recent successful experimental
results with an isostructural MOF platform constructed from Zr and select rare-earth
metals, we have applied quantum density functional theory methods to select MOFs
from this series. Periodic calculations were used to calculate structural properties of the
pure MOFs in good agreement with X-ray crystal structures. Gas-phase cluster models
were then used to study the adsorption properties and reaction pathways for the
decomposition of CWAs and simulants. Solvent effects were included both explicitly and
implicitly. Results provide guidance toward ligand functionalization and metal site
selection.

This work is supported by the Laboratory Directed Research and Development Program
at Sandia National Laboratories. Sandia National Laboratories is a multi-mission lab
managed and operated by Sandia Corp., a wholly owned subsidiary of Lockheed Martin
Corporation, for the US DOE’s NNSA under contract DE-AC04-94AL85000.
INOR 5
Optimizing toxic chemical removal through defect-induced UiO-66-NH metal-
2
organic framework
Greg W. Peterson1, [email protected], Matthew Destefano2, Sergio J.
Garibay2, Ann Ploskonka5, Morgan Hall1, Christopher J. Karwacki4, Joseph T. Hupp2,
Omar K. Farha3. (1) ECBC, Aberdeen Proving Ground, Maryland, United States (2)
Northwestern Univ, Evanston, Illinois, United States (3) Chemistry, Northwestern
Unversity, Glenview, Illinois, United States (4) US Army, Edgewood Chemical Biological
Center, Churchville, Maryland, United States (5) Leidos, Inc., Gunpowder, Maryland,
United States
Over the past several years, it has been well-established that defects can be
systematically introduced into metal-organic frameworks (MOFs). Within the UiO-66-
type metal-organic frameworks, this becomes especially important, as the relatively
small pore apertures can be widened, increasing diffusion and access to active sites
within the material. In this study, three UiO-66-NH MOFs were synthesized with varying
2
degrees of defects. The materials were characterized to understand what types of
defects were present, and the effects of defects on the removal of several gaseous and
liquid toxic chemicals, including chemical warfare agents, were determined. The study
showed that there may be an optimal number of defects when considering broad
reactivity.
INOR 6
Photocatalytic oxidation of bromide to bromine by using ruthenium polypyridyl
complexes
I-Jy Chang, [email protected], Kelvin Yun-Da Tsai. Chemistry, National Taiwan
Normal Univ, Taipei, Taiwan
Ruthenium polypyridyl complexes undergo facile redox chemistry at it electronic
excited-state. Photoinduced electron transfer (ET) for Ruthenium polypyridyl-
dinitrobenzene donor-acceptor complexes has been designed to assess the amino-acid
side chain effect on ET reactions. Flash-quenched technique are employed to design a
photocatalytic oxidation of bromide to bromine.
Excited [Ru(bpy) ]2+ is quenched by ArN + (bromobenzenediazonium) to produced long-
3 2
lived [Ru(bpy) ]3+ species. With bromide present in the solution, [Ru(bpy) ]3+ oxidize it to
3 3
give bromine radical. Bromine radicals disproportionate to produce final product of
bromine. The turn-over number for this photocatalytic oxidation of bromide to bromine is
116. Complexes with substituted bipyridine ligands have been prepared to fully
understand the relationship between redox potentials and photocatalytic behavior.
INOR 7
Multimetallic systems for the photocatalytic production of fuels from abundant
sources
Claudia Turro, [email protected]. Ohio State Univ, Columbus, Ohio,
United States
The search for renewable, clean sources of energy is critical for the future of the planet.
The use of abundant sunlight to generate electricity or to efficiently and catalytically
transform inexpensive simple molecules into clean fuels, such as hydrogen from water
and formic acid from and carbon dioxide, remains a challenge. Systems for efficient
conversion of sunlight into chemical fuels requires strong light absorption that is well-
matched to the solar spectrum, catalysts that effect the desired transformation, followed
by combining the light absorber (LA) with the catalyst (CAT) into functional LA-CAT
architectures. Current LAs used in these applications typically do not absorb the entire
solar spectrum efficiently from the ultraviolet, UV, to the near-IR (infrared) range, such
that some fraction of photons that make up the solar spectrum are not utilized. We have
developed new Rh (II,II) complexes that serve as dyes that absorb light strongly
2
throughout the visible region and into the near-IR. These compounds are capable of
undergoing excited state redox processes, such as the photoinduced reduction of
methyl viologen and known cobalt electrocatalysts that produce H from protons, as
2
measured using steady-state photolysis in the presence of a sacrificial donor and using
transient absorption. In addition, new dirhodium complexes that act as catalysts for the
reduction of water to hydrogen and carbon dioxide to formic acid will be presented. The
variation of the bridging ligand from formamidinate to acetamide and acetate in these
dirhodium catalysts results in increased selectivity toward carbon dioxide reduction
instead of hydrogen formation. Both proton and carbon dioxide reduction are believed to
proceed via the formation of an axial hydride intermediate, the characterization and
reactivity of which will be presented.
INOR 8
Thermally and photochemically activated diradicals: Applications to catalysis and
nanoreagents for CO reduction
2
Jeffrey M. Zaleski, [email protected]. Indiana Univ, Bloomington, Indiana, United
States
Environmental impacts of continued CO production have led to an increased need for
2
new methods of CO removal and energy development. Nanomaterials are of special
2
interest for these applications, due to unique chemical and physical properties that allow
for highly active surfaces. Here, we successfully synthesize alloy, core-shell and
nanodendrite-branched Au nanoparticles in different shapes (nanoprisms, hexagonal
nanoplates, and octahedral nanoparticles) by a universal and facile method for site-
selective metal deposition. This strategy involves coupling galvanic replacement
between Ag layers in Au@Ag core-shell nanoprisms and H PdCl with a co-reduction
2 4
process of silver and palladium ions. Synthesis of AgPd nanodendrite-tipped (4.14–
11.47 wt% Pd) and -edged (25.25–31.01 wt% Pd) Au nanoparticles could be controlled
simply by tuning the concentration of H PdCl . More importantly, these multi-component
2 4
AgPd nanodendrite-modified Au nanoparticles show exceptional electrocatalytic
performance for CO reduction. AgPd nanodendrite-edged Au nanoprisms show very
2
low potentials (–0.66 V vs. SCE) for the reduction of CO to formic acid, and exhibit
2
higher current efficiencies (49%) than Au, Au@Ag, and AgPd nanodendrite-tipped Au
nanoprisms in aqueous electrolytes. Moreover, the AgPd nanodendrite-tipped and -
edged Au nanoprisms show much higher selectivity and current efficiency for CO
2
reduction to CO in organic electrolytes (85–87%) than Au and Au@Ag nanoprisms (43–
64%). The high performance of these particles for CO reduction is attributed to the
2
unique structure of AgPd nanodendrite-modified Au nanoparticles and synergistic
effects among Ag, Pd, and Au. These results indicate that AgPd nanodendrite-modified
Au nanoparticles show promising potential for application in CO conversion into useful
2
fuels.

INOR 9
Luminescent nanoparticles coated with metal complexes for biomedical
applications
Zoe Pikramenou, [email protected]. University of Birmingham, Edgbaston,
Birmingham, United Kingdom
Gold nanoparticles offer a unique opportunity to incorporate multiple molecular
luminescent metal complexes into a single nanoscale architecture for signal detection
without engaging in lengthy synthetic procedures for incorporation of multiple labels. We
have incorporated surface-active lanthanide, ruthenium or iridium metal complexes on
the gold nanoparticles. In our approach we use fluorinated surfactants and peptides for
coating the gold surface together with the metal complex to stabilize the nanoparticle
and target sensing functions. The nanoparticles possess photophysical properties
derived for the metal center. The visible luminescence of the probes with long Stokes
shift and long lifetimes which are signature of the metal properties provide ideal
detection of the nanoparticles in cells away from autofluorescence signal. We have
established the nanoparticle uptake in cells using analytical, electron and optical
microscopy techniques. More recently lifetime-based imaging techniques have shown to
be ideal for detection of the coated nanoparticles.

INOR 10
Designing and understanding catalysis with high valent metals
Aaron L. Odom, [email protected], Tanner McDaniel, Brennan Billow, Kelly
Aldrich. Chemistry Department, Michigan State University, East Lansing, Michigan,
United States
Catalysis is perhaps the most important expression of chemical ingenuity and is the
center of many proposed solutions to societal problems including energy storage, new
treatments for disease, and new materials for applications in our daily lives. Catalysis is
also one of the most important methods for building wealth worldwide with an estimated
35% of the global GDP contributed by catalysis. While tools for understanding catalysts
containing low valent metals have developed steadily for over half a century, high valent
metal catalysis is largely optimized using combinatorial methods in amalgamation with
the chemist’s intuition. This is despite the fact that high valent catalysis contributes
enormously to industrial reactions like olefin polymerization and oxidation chemistry.
The main ingredient lacking for high valent catalyst design has been a method for
quantifying the donor abilities of the myriad of different ancillary ligands employed. In
this presentation, a brief overview of an approach for measuring donor abilities to high
valent metals will be given followed by applications in understanding ligand binding and
modeling catalytic reactions to discover quantitatively how sterics and electronics
contribute to reaction rates.
INOR 11
Hydrogen-atom non-innocence of an azanidodithiolate pincer ligand
Alan F. Heyduk, [email protected], Kyle E. Rosenkoetter, Bronte Charette. Chemistry,
University of California, Irvine, Irvine, California, United States
The azanidodithiolate pincer ligand derived from bis(2-mercapto-p-tolyl)amine is
capable of storing one proton and one electron when coordinated to a metal center.
Coordination of the ligand to nickel and cobalt in the doubly deprotonated state affords
complexes of the form [SN(H)S]ML (M = Ni, Co; L = phosphine) with a secondary amine
donor that contains an acidic proton. Electrochemical and acid-base measurements
have been used to determine N–H BDFEs while reactivity studies have been used to
assess the ability of this hydrogen atom to participate in small-molecule activation
reactions.
INOR 12
Follow the protons: Directly monitoring proton transfer mechanisms with
ultrafast continuum mid-IR spectroscopy
Ashley M. Stingel, Poul B. Petersen, [email protected]. Department of Chemistry
and Chemical Biology, Cornell University, Ithaca, New York, United States
Proton-coupled electron transfer reactions are central to biological and biomimetic
energy transfer processes. Here the electron transfer reaction can be monitored directly
through a variety of experimental methods but the proton transfer contribution have to
be inferred indirectly by how it affect the electron transfer process. This is typically done
by observing how the electron transfer rate change upon deutoration or changes in the
pH. Alternatively, the proton transfer process can be inferred indirectly through
electronic state dynamics observed in transient visible spectroscopy. However, due to
the indirect nature this can lead to controversial interpretations. We introduce a new
method for examining the proton transfer mechanisms by directly monitoring the
chemical bonds that are breaking and forming during the proton transfer reaction. These
are medium and strong hydrogen-bonded NH or OH groups, which exhibit very broad
(300-1000 cm-1) vibrational features. Using ultrafast continuum mid-IR spectroscopy, we
capture the entire vibrational spectrum with sub-100 fs time resolution and monitor the
very broad vibrational features associated with proton transfer. We illustrate the method
by examining the excited state double proton transfer reaction of the 7-azaindole
homodimer and the asymmetric heterodimer of 7-azaindole with acetic acid. Ultrafast
continuum mid-IR spectroscopy provide a direct means for determining proton transfer
mechanisms by directly monitoring the chemical bonds that are breaking and forming
during the proton transfer reaction.
INOR 13
Specific ion effect manifested in oxidation of ammonium salts and inorganic
substrates
Katherine L. Hull1, [email protected], Amy Cairns3, Marium Haq2,4. (1)
Aramco Research Center-Houston, Houston, Texas, United States (2) Aramco
Research Center-Houston, Houston, TX, Texas, United States (4) University of
Houston, Houston, Texas, United States
Specific ion effects have been observed to play a role not only in macromolecular
biological systems such as proteins but also in inorganic systems such as colloidal
nanoparticles. The relative importance of ion-water interactions versus ion-ion pairing
continues to be a topic of investigation. For poorly hydrated ions such as ammonium,
though, it is expected that ion-ion interactions may dominate any solution phase
behavior that is governed by ion effects. Recently, when exploring systems capable of
oxidizing pyrite for oilfield applications, sodium bromate and ammonium persulfate were
found to react synergistically with iron sulfide as well as other inorganic substrates.
Underlying the synergism is a reaction between bromate and ammonium, where
oxidation at low temperature visibly produces Br (g) and liberates H+.
2

The approach was tailored to produce a series of strong mineral acids by reacting
sodium bromate with alternative ammonium-based salts, producing in situ generated
acids that are convenient for subterranean applications. A series of anions were
explored including persulfate, sulfate and other polyatomic ions as well as various
halides. As the ammonium salts were oxidized with sodium bromate, their products
were analyzed by electrospray ionization mass spectrometry (ESI-MS), inductively
coupled plasma (ICP), and elemental analysis. Real-time FT-IR and multinuclear NMR
solution analyses were also performed to observe the formation of intermediate species.

Each ammonium-based salt produced an oxidized nitrogen species, whereby the
activation temperatures and rates were dictated by anion selection. Ammonium
persulfate was found to react with sodium bromate at ~80 °C, whereas ammonium
chloride required ~150 °C, and ammonium fluoride >200 °C. ESI-MS confirms product
formation such as the conversion of persulfate to sulfate, the apparent complete loss of
nitrogen, and the presence of some Br- in solution though the majority of bromate is
converted to bromine. FT-IR and NMR established the time scales over which the
reactions occurred as well as the identity of intermediates.

While this study elucidates the pathway for pyrite oxidation and acid generation, it
further contributes to the growing body of knowledge of the role of counter ions in
solution, particularly when solvent effects are minimized. Furthermore, processes