Agenda

New X-ray tools for investigating MOF and COF

Oct. 4, 2016 Afternoon

(54-130)

54 is the cafeteria building.

to get to #130, enter the cafeteria main door, keep left, walk towards the cashier, then turn left.

Berkeley lab map

Chair – Chenhui Zhu (ALS, LBL)

140-220pm Prof. Omar Yaghi, UC Berkeley / LBL

MOF/COF Frontier/Challenges

230-310pm Prof. Osamu Terasaki, Stockholm University and KAIST

Direct Observation of Collective Behavior of Adsorbates in Porous Crystal IRMOF-74 through In-Situ Small Angle X-ray Scattering (SAXS)

310-330 pm coffee break

Chair - Christine Beavers (ALS, LBNL)

330-410pm Prof. Hans-Beat Bürgi, University of Zurich

"3D Single Crystal Diffuse Scattering - Measurement and Interpretation"

410-440pm Dr. David Britt, Matrix Sensors, Inc.

"Metal-Organic Frameworks to Enable Low-cost Distributed Chemical Sensors"

440-510pm Dr. Tomce Runcevski, UC Berkeley

"In situ X-ray Powder Diffraction studies of Metal-Organic Framework Materials "

Oct. 5^th, 2016 Morning

Chair - Mike Brady (ALS/MF, LBL)

830-910AM Dr. Yi Liu, Molecular Foundry, LBL

“Functional Organic Frameworks in non-Powdery Forms”

910-940AM Mr. Mathieu R. Bosch, Texas A&M

"Successive Single-crystal X-ray Diffraction Enables Stepwise MOF Synthesis"

935-10AM Coffee break

Chair – Yi Liu (Molecular Foundry, LBL)

10-1040AM Dr. Craig Brown, National Institute of Standard Technology

"Structural and Dynamic Studies of Adsorbates in Metal-Organic Frameworks"

1040-1110AM Mr. Yingbo Zhao, UC Berkeley

Integration of Nanoscale Metal-organic Frameworks with Inorganic Nanostructures:

Precision in synthesis and application in catalysis

1110-1140AM Mr. Miguel Gonzalez, UC Berkeley

"Structural Characterization of Framework–Guest Interactions in Metal–Organic Frameworks by Single-Crystal X-ray Diffraction"

1140-1210 Dr. Mike Brady, ALS/MF, LBNL

Investigating Nanostructured Organic Frameworks and Porous Polymers with X-ray Scattering

Noon lunch at ALS patio

Chair - Jinghua Guo, ALS, LBL

130-210PM Dr. Cheng hao Wu, ALS, LBL

"In-situ and operando soft x-ray absorption spectroscopy apparatus @ BL8.0.1 and BL 6.3.1.2"

210-240PM Dr. Walter Drisdell, JCAP, LBL

"In situ X-ray absorption spectroscopy of gas adsorption in MOF"

240-310PM Stephen Meckler, MF, LBL

"Informing Microporous Thin Film Membrane Design Through X-Ray Scattering and Absorption Techniques "

ALS Upgrade news

https://newscenter.lbl.gov/2016/10/03/als-u-x-ray-project-takes-a-step-forward/

ALS U workshop report "Science Opportunities with Diffraction-Limited Soft X-Ray Beams"

http://als.lbl.gov/wp-content/uploads/2016/09/sxr_workshop_report.pdf

Abstracts:

Osamu Terasaki

David Britt

"Metal-Organic Frameworks to Enable Low-cost Distributed Chemical Sensors"

As connected devices proliferate in our society we have begun to view each node as a “bundle of sensors” that generates a stream of data we can use to understand and control our lives. The list of ubiquitous sensors, which now includes accelerometers, thermometers, microphones, and cameras among others, continues to grow. From this list chemical sensors are notably absent. Their omission owes to a combination of faults, including cost, size, power requirement, and longevity. We aim to take advantage of the unique class of metal-organic framework (MOF) materials to establish a platform technology for low-cost chemical sensing. I will discuss the advantages offered by MOFs in this domain, as well as the technical obstacles that remain and our efforts to overcome them.

Yingbo Zhao

"Integration of Nanoscale Metal-organic Frameworks with Inorganic Nanostructures: Precision in synthesis and application in catalysis"

Conformal and oriented metal-organic frameworks thin film enclosing arbitrary nanostructures (substrates, nanowires, nanocrystals) are fabricated with precisely controlled thickness and pristine interface. This is achieved by atomic layer deposition of aluminum oxide on the substrates and addition of a tetra-topic porphyrin based linker, 4,4′,4″,4‴-(porphyrin-5,10,15,20-tetrayl)- tetrabenzoic acid (H₄TCPP), to react with alumina and make MOF [Al₂(OH)₂TCPP] enclosures. Alumina thickness is precisely controlled from 0.1 to 3 nm, thus allowing control of the MOF thickness from 10 to 50 nm. Electron microscopy and grazing angle X-ray diffraction confirm the order and orientation of the MOF by virtue of the porphyrin units being perpendicular to the substrate surface. These features of the MOF enclosure enable us to use surface-enhanced Raman spectroscopy to directly track the porphyrin metalation process of the MOF enclosing octahedral silver nanocrystals. When metalated with cobalt, the Al₂(OH)₂TCPP-Co thin film functions as catalyst for the selective and efficient reduction of carbon dioxide to carbon monoxide (CO) in aqueous electrolytes with a selectivity for CO beyond 76% and stability over 7 h with a per-site turnover number (TON) of 1400. This electrochemical catalytic activity is unique to the thin film form of the MOF (below 100 nm) and depends strong on the film thickness. This research presents a generalizable method to produce structurally well-defined nano-MOF composite material that has extraordinary functions.

3D Single Crystal Diffuse Scattering - Measurement and Interpretation

H.B. Bürgi^a,b, R. Frison^b, T. Weber^c, C. Hoffman^d, ^aDepartment of Chemistry and Biochemistry, University of Berne; ^bDepartment of Chemistry, University of Zürich; ^cLaboratorium für Kristallographie, ETH Zürich, Switzerland; ^dOak Ridge National Laboratory, Oak Ridge, TN, USA.

Many of the useful and interesting properties of MOFs, COFs and other crystalline materials are due to crystal defects. Defects manifest themselves by diffuse scattering interspersed between the Bragg reflections. The total scattering, Bragg and diffuse, contains information on the periodic portion of the total scattering density including its chemically unreasonable parts on one hand and the nature of the underlying crystal defects as well as the correlation between them on the other hand.

Nowadays reasonably accurate measurement of complete 3D total scattering is possible at synchrotrons with their high flux of X-rays and low-noise, energy discriminating pixel detectors. Several neutron scattering facilities provide stations for measuring 3D diffuse scattering patterns. Careful data processing is mandatory, especially with respect to background corrections. Diffuse data sets may contain millions to hundreds of millions of observations. Their handling and interpretation thus requires substantial computing resources.

Interpretation of such data relies primarily on two tools [1]: 1) analysis of the 3D-PDF, i.e. the Fourier Transform (FT) of the total scattering intensity. The 3D-PDF is the non-periodic Patterson function of the disordered crystal just like the FT of the Bragg intensities is the periodic Patterson function P of an ordered crystal. If a good model of the average, periodic structure is available, the 3D-ΔPDF=3D-PDF-P is usually more informative. It represents the deviations from periodicity in terms of inter-nuclear vectors, their intensity and a between-atoms temperature factor. 2) The disordered structure may be modeled with Monte Carlo (MC) simulations constrained to match the average structure. In practice it is often useful to alternate between MC modeling and the 3D-ΔΔPDF=3D-ΔPDF(exp)-3D-ΔPDF(MC model). The information from 3D total scattering patterns is necessarily superior to that of 1D powder patterns as is the information from 3D single crystal Bragg data compared to powder diagrams.

The general comments above will be illustrated with pictures showing total scattering and a 3D-PDF/MC interpretation of X-ray and neutron data measured for the same compound.

[1] For a recent review see: T.R. Welberry, T. Weber, Cryst. Rev. 22 (2016) 2-78.

Structural and Dynamic Studies of Adsorbates in Metal-Organic Frameworks

Craig Brown, NIST

Adsorption of molecules in functionalized and high surface area microporous materials is of technological importance in a multitude of areas ranging from chemical separations to energy storage. Over the past several years we have focused our research efforts on understanding the properties of metal-organic frameworks (MOFs) and zeolites for storage and separations of industrially important small molecules such as hydrogen, oxygen, carbon dioxide, noble gases, and short chain organics. Besides the geometrical and porosity control in either class of materials, the properties of metal-organic frameworks can be tuned to optimize electrostatic interactions by exposing open metal cation sites.

Here, I will briefly illustrate some of the capabilities available at the NIST Center for Neutron Research and reflect on some of the characteristics of neutrons that make them suitable for the study of a wide variety of materials under a variety of conditions. A comparison to X-ray scattering capabilities will be made and the complementarity of approaches discussed. An in-depth look at results obtained on MOFs illustrate the power, and limitations, of diffraction in elucidating many of the governing characteristics of these material properties and the interactions with the guest molecules.

Title: In-situ and operando soft x-ray absorption spectroscopy apparatus @ BL8.0.1 and BL 6.3.1.2

Cheng Hao Wu

Abstract: Soft x-ray absorption spectroscopy (sXAS) is an element-specific and chemical-environment-specific technique, which allows us to probe the light elements (e.g., from B to Mg) and first-row 3d metals. At BL8.0.1 and BL 6.3.1.2, specially designed gas cell and liquid cell makes it possible to study ambient-condition catalytic and electrochemical systems in situ and operando, using traditionally vacuum-requiring sXAS. I will present a few recent examples on catalytic and electrochemical systems using in-situ and operando sXAS, to demonstrate the capability of this technique, which can be a valuable tool for many other gas-phase reaction and electrochemistry systems, including the ones involving various MOF/COF materials.