Journal of the American Chemical Society

Methane Storage in Paddlewheel-Based Porous Coordination Cages

Casey A. Rowland, Gregory R. Lorzing, Eric J. Gosselin, Benjamin A. Trump, Glenn P. A. Yap, Craig M. Brown, and Eric D. Bloch
J. Am. Chem. Soc.
DOI: 10.1021/jacs.8b05780
Publication Date (Web): August 18, 2018
Copyright © 2018 American Chemical Society

Although gas adsorption properties of extended three-dimensional metal-organic materials have been widely studied, they remain relatively unexplored in porous molecular systems. This is particularly the case for porous coordination cages for which surface areas are typically not reported. Herein, we report the synthesis, characterization, activation, and gas adsorption properties of a family of carbazole-based cages. The chromium analog displays a coordination cage record BET surface area of 1235 m2/g. With precise synthesis and activation procedures, two previously reported cages similarly display high surface areas. The materials exhibit high methane adsorption capacities at 65 bar with the chromium(II) cage displaying CH4 capacities of 194 cm3/g and 148 cm3/cm3. This high uptake is a result of optimal pore design, which was confirmed via powder neutron diffraction experiments.

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Soft Matter Journal Cover

Branching and Alignment in Reverse Worm-like Micelles Studied with Simultaneous Dielectric Spectroscopy and RheoSANS†

John K. Riley, Jeffrey J. Richards, Norman J. Wagner and Paul D. Butler
Volume 14 | Number 26 | 14 July 2018 | Pages 5335–5538
ISSN 1744-6848 | DOI: 10.1039/c8sm00770e

Topology and branching play an important but poorly understood role in controlling the mechanical and flow properties of worm-like micelles (WLMs). To address the challenge of characterizing branching during flow of WLMs, dielectric spectroscopy, rheology, and small-angle neutron scattering (dielectric RheoSANS) experiments are performed simultaneously to measure the concurrent evolution of conductivity, permittivity, stress, and segmental anisotropy of reverse WLMs under steady-shear flow. Reverse WLMs are microemulsions comprised of the phospholipid surfactant lecithin dispersed in oil with water solubilized in the micelle core. Their electrical properties are independently sensitive to the WLM topology and dynamics. To isolate the effects of branching, dielectric RheoSANS is performed on WLMs in n-decane, which show fast breakage times and exhibit a continuous branching transition for water-to-surfactant ratios above the corresponding maximum in zero-shear viscosity. The unbranched WLMs in n-decane exhibit only subtle decreases in their electrical properties under flow that are driven by chain alignment and structural anisotropy in the plane perpendicular to the electric field and incident neutron beam. These results are in qualitative agreement with additional measurements on a purely linear WLM system in cyclohexane despite differences in breakage kinetics and a stronger tendency for the latter to shear band. In contrast, the branched micelles in n-decane (higher water content) undergo non-monotonic changes in permittivity and more pronounced decreases in conductivity under flow. The combined steady-shear electrical and microstructural measurements are capable, for the first time, of resolving branch breaking at low shear rates prior to alignment-driven anisotropy at higher shear rates.

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Chemical Communications, Royal Society of Chemistry

Gas Adsorption in an Isostructural Series of Pillared Coordination Cages

Eric J. Gosselin, Gregory R. Lorzing, Benjamin A. Trump, Craig M. Brown and Eric D. Bloch
Issue 49, 2018
Department of Chemistry & Biochemistry, University of Delaware, Newark, USA
Center for Neutron Science, Department of Chemical and Biomolecular Engineering, University of Delaware
Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, USA

The synthesis and characterization of two novel pillared coordination cages is reported. By utilizing 1,4-diazabicyclo[2.2.2]octane (dabco) as a pillar with increased basicity as compared to pyrazine or 4,4′-bipyridine, a stable copper-based material was prepared. Extending this strategy to iron(II) afforded an isostructural material that similarly retains high porosity and crystallinity upon solvent evacuation. Importantly, the iron solid represents a rare example of porous iron paddlewheel-based metal–organic material that is stable to solvent evacuation. Neutron powder diffraction studies on these materials indicate the triangular and square windows of the cage are prime ethane and ethylene adsorption sites.

Thomas H. Epps, III Elected as a Fellow into the RSC

Thomas H. Epps, III, elected as a Fellow into the Royal Society of Chemistry

Thomas H Epps, III, the Thomas and Kipp Gutshall Senior Career Development Chair in Chemical and Biomolecular Engineering at University of Delaware and Director for the Center for Molecular & Engineering Thermodynamics (CMET), has been admitted as a Fellow of the Royal Society of Chemistry (RSC), a UK-based professional society with worldwide membership. The Fellow of the Royal Society of Chemistry (FRSC) designation is given to elected fellows who have made significant contributions to the chemical sciences.

“It is a great honor to be appointed as a Fellow of the Royal Society of Chemistry,” says Epps. “Several of my colleagues at UD are Fellows of the RSC, along with other people who I admire in the polymers community in the United States and abroad. It is a great privilege to become a part of this esteemed group in chemistry. I am extremely grateful to all of my students, postdocs, and collaborators who have contributed to my activities.”

To learn more about Epps’s research, click here. For more information about the RSC, visit their official site.

Understanding Porous Materials

Yun Liu (left) and Wei-Shan Chiang adjust a syringe pump used to control gas pressure

New method could help quantify untapped natural gas reservoirs

More than 30 states have shale formations that harbor natural gas underground, according to the Energy Information Administration. But industry experts can’t agree on exactly how much fuel is inside. That’s because natural gas and other hydrocarbons lie inside nano-scale, difficult-to-measure pores in shale rocks, which have properties that are not yet understood. “If you want to estimate the storage capacity of shale gas, you need to understand materials that store them,” said Yun Liu, an affiliated associate professor of chemical engineering at the University of Delaware and a physicist at the National Institute of Standards and Technology (NIST) Center for Neutron Research.

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Read publication in Nature Communications

2018 Sustained Research Prize

Professor Norman J. Wagner, Center for Neutron Science, Department of Chemical & Biomolecular Engineering, University of Delaware

NSSA Announces the 2018 Prize Recipients

Professor Norman Wagner
University of Delaware
is the recipient of the
2018 Sustained Research Prize
of the Neutron Scattering Society of America (NSSA)
with the citation:
“For his seminal and sustained contributions to our understanding of soft condensed matter physics using neutron scattering.”
View Neutron Scattering Society of America Newsletter

Want a Tougher Space Suit? Just Add Liquid

Astronauts don bulky suits to protect themselves as they “walk” outside the International Space Station.

A New Material Might Give Astronauts Better Space Suits that are Strong, Thin and Light

Space is dangerous. It’s filled with tiny rocks that can poke holes in an astronaut’s spacesuit. If oxygen leaks out of it, that space traveler is in trouble. To better protect space travelers, researchers are designing a new type of material to toughen those protective suits. And this material is about to get its first big test in space itself.

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Neutron Day 2017

Neutron Day 2017 at Perkins Student Center, Ewing Room on November 8, 2017 from 9:00 a.m. – 3:30 p.m.

“Solving Grand Challenge Problems in Science & Engineering with Neutrons”
November 8, 2017, 9:00 a.m. – 3:30 p.m., Perkins Student Center, Ewing Room, 325 Academy Street, Newark, DE 19716

2017 Neutron Day Program, Parking Map & Building Locations: Click Here
Poster Presentation List: Click Here

Sponsored by the Center for Neutron Science
NIST Center for Neutron Research (NIST-NCNR)
University of Delaware College of Engineering
Department of Chemical & Biomolecular Engineering
Department of Materials Science & Engineering.

Center for Neutron Science, University of Delaware, and NIST Cooperative Agreement beginning September 1, 2017

Executive Summary

We propose a cooperative agreement between the Center for Neutron Science (CNS) at the University of Delaware (UD) and the NCNR to focus on advancing neutron scattering metrology through the use of SANS, VSANS, Neutron Reflectometry and NSE for research addressing grand challenges in the areas of sustainable energy, human health, nanomaterials as well as engineering the tools of scientific discovery. The goals of this cooperative agreement include the promotion and development of the use of neutron scattering science by scientists at the NCNR, NIST and the broader community in science and engineering, including macromolecular, colloid, and condensed matter science and chemistry. The seven faculty, nine NIST staff and 12 doctoral students and postdocs currently or proposed to be funded by the CNS have significant, collective experience using neutron scattering in research, and in the design, development, maintenance and optimization of neutron scattering instrumentation. The PI (Wagner) has directed the CNS at UD for a decade, is a fellow of the Neutron Scattering Society of America, was elected to the National Academy of Engineering and the National Academy of Inventors, is a regular user of the NCNR and contributes to NCNR activities and the development of neutron scattering instrumentation world-wide. Collectively, the faculty have trained over 100 doctoral students and postdoctoral scientists in neutron scattering science and have an extensive scientific publication record with high visibility, as also evidenced through many professional awards, and numerous plenary and keynote invited lectures. Many UD doctoral students are or have been in residence at the NCNR for a significant fraction of their doctoral dissertation, which stems from strong, existing collaborations with NCNR scientists, including many co-publications. At least three UD students and postdocs have recently gone on to become NRC postdoctoral fellows at the NCNR. n-SOFT research staff and industrially supported postdocs at the NCNR in collaboration with n-SOFT are a consequence of UD CNS research. The UD CNS has trained generations of undergraduate, graduate and postdoctoral students in neutron scattering methods at the NCNR, and many continue using these facilities as part of their current careers in academia and industry.

The nine, staff to be supported under this cooperative agreement have distinguished accomplishments at the NCNR, making significant contributions to the NCNR’s new data acquisition software (NICE), the development of VSANS, as well as significant scientific advances in soft matter using NCNR resources. The beamline scientists will support the SANS, USANS, VSANS and reflectometry instruments. The beamline scientist Dr. Yun Liu is also a Research Associate Professor at UD and as such, serves as the primary thesis advisor and as co-advisor for a number doctoral students, lectures on neutron scattering at UD and other Universities, as well as teaches at the NCNR summer school. The computer scientists and engineers support NICE and the computational infrastructure of the NCNR more broadly. The mechanical design and draftsman and research scientists are integral to the design, construction, and commissioning of the new VSANS instrument (planned 2018). This proposal also includes a novel collaboration with NCNR staff to develop new interfacial rheology-neutron reflectometry sample environment that will be made available to the broader scientific user community.

The UD faculty, beamline staff scientists, graduate students and postdocs are uniquely qualified to conduct the proposed research activities and to provide excellent research assistance to U.S. neutron researchers using the NCNR. The new sample environments and data analysis methods developed in this proposed work will be made available to promote neutron scattering science more broadly through the NCNR. The close proximity of UD to NCNR, extensive track record of collaborative research, publication, and teaching jointly between NCNR and UD scientists and students greatly facilitate the strong integration of the staff into the activities of the NCNR as described in the management plan. UD is also providing special, dedicated human resources to support the UD/NCNR staff, who can effectively meet the employment needs of the proposed staff. UD students, postdocs and faculty will be in residence at the NCNR during the course of this project and will contribute to the education and support of U.S. researchers using NCNR facilities. This includes expanding our K-12 activities by providing more and improved learning modules for high school science teachers through UD’s Learning Library, which were developed by UD CNS students to educate high school students in the basics of neutron scattering and its uses. CNS faculty also offer a popular graduate course in Scattering Methods in Soft Matter that will be regularly offered during the execution of this cooperative agreement, and also hosts the highly regarded biannual “Neutron Day”, which is a regional celebration of neutron science. Importantly, UD graduates educated in neutron scattering methods and science have gone on to employment at NCNR and NIST more broadly, such that this talented pool of doctoral students and postdocs to be supported under this cooperative agreement are a source of expertise for future staffing.

Neutron Day and $8.7 Million for UD

NormWagnerNeutron3: Dan Neumann and Norm Wagner stand at the lectern in the Ewing Room of Perkins Hall on Neutron Day.

Scientists Discuss Promise of New Agreement Between UD and NIST

The day began with coffee, bagels, and some hearty discussions about experimental data. The University of Delaware’s fifth Neutron Day was held Wednesday, Nov. 8 in Perkins Hall and the Patrick Harker Interdisciplinary Science and Engineering (ISE) Lab. This year, Neutron Day was a celebration of more than its namesake subatomic particle. UD’s Center for Neutron Science (founded in 2007) recently entered into another cooperative agreement with the National Institute of Standards and Technology (NIST) Center for Neutron Research (NCNR). Under this new agreement, UD’s Center for Neutron Science will advance the field of neutron scattering by developing new techniques, applying these techniques to new applications, and training the next generation of neutron scientists. The agreement began on Sept. 1 with $1.7 million of funding and projects a funding total of more than $8.7 million through Aug. 31, 2022, which brings the total funding to the center to well over $30 million over the past ten years. UD’s Center for Neutron Science is directed by Norm Wagner, the Unidel Robert L. Pigford Chair in Chemical and Biomolecular Engineering. He is a fellow of the Neutron Scattering Society of America, a regular user of NCNR facilities and a contributor to the development of neutron scattering instrumentation.

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