Synthesis, Characterization, Modeling and Applications of Functional Porous Materials: Porous Materials I
Sponsored by: ACerS Basic Science Division
Program Organizers: Lan Li, Boise State University; Winnie Wong-Ng, National Institute of Standards and Technology; Kevin Huang, University of South Carolina
Monday 8:00 AM
October 10, 2022
Room: 325
Location: David L. Lawrence Convention Center
Session Chair: Lan Li, Boise State University
8:00 AM Introductory Comments
8:05 AM Invited
Neutron and X-ray Scattering to Characterize Adsorbents and Their Hosts: Hayden Evans1; Ryan Klein2; Benjamin Trump1; Craig Brown1; 1NIST; 2NREL
Adsorption of molecules in functionalized and high surface area metal-organic frameworks (MOFs) is of emergent technological importance in a multitude of areas. We have been studying the properties of MOFs and other porous materials for storage and separations of industrially important small molecules. Besides the geometrical and porosity control available in MOF chemistry, the properties of the frameworks can be tweaked to elevate electrostatic interactions by exposing open metal cation sites or through enhanced van der Waals contacts via functionalizing ligands and introducing flexibility. We will highlight optimized interactions of hydrogen with open metal sites to obtain room temperature adsorption, a range of dynamic frameworks pore binding in MOF-like materials, and small pore MOFs which are robust to moisture and are highly selective for a series of separations. These results illustrate the governing characteristics of these material properties and the interactions with the guest molecules.
8:35 AM Invited
Energetic Insights into Encapsulation of Molybdenum Oxide and Carbide Particles in Zeolite Y: Xianghui Zhang1; Margaret Reece1; Andrew Strzelecki1; Cody Cockreham1; Vitaliy Goncharov1; Houqian Li1; Kyungmin Yim2; Jinsoo Kim2; Junming Sun1; Hui Sun3; Baodong Wang4; Xiaofeng Guo1; Hongwu Xu5; Su Ha1; Yong Wang1; Di Wu1; 1Washington State University; 2Kyung Hee University; 3East China University of Science and Technology; 4National Institute of Clean-and-Low Carbon Energy ; 5Arizona State University
Encapsulation of transition metal oxides and carbides in zeolites leads to effective catalytic particles and clusters for methane conversion and biomass upgrading. Here we report our recent experimental studies on the thermodynamics of molybdenum trioxide (MoO3) and molybdenum carbide (Mo2C) formation under confinement in zeolite Y (FAU) Si/Al ratio varies employing high-temperature oxide melt solution calorimetry. Specifically, at the same Mo loading, the enthalpies of formation for MoO3/FAU and Mo2C/FAU from constituent oxides and carbides become less endothermic as the Si/Al ratio increases. Encapsulation of Mo2C is energetically more favorable compared with the confinement of MoO3 in zeolite Y by ∼30 kJ/mol per tetrahedron unit. Unlike MoO3 which has high redox transition flexibility to achieve lower energetic states, it is the strong bonding at the Mo2C–FAU interfaces that compensate for the energetic deficiency to achieve highly dispersed Mo2C particles. Well-dispersed Mo2C was also synthesized on Ni-Mo2C/FAU for methane-steam reforming.
9:05 AM Invited
Metal Organic Framework Compound, [Ni(4,4’-bipyridine)Ni(CN)4]n, Based on Pillared Cyanonickelate (PICNIC) Architecture: Winnie Wong-Ng1; Jeffrey Culp2; Yu-Sheng Chen3; Daniel Siderius1; Lan Li4; 1National Institute of Standards and Technology; 2NETL; 3University of Chicago; 4Boise State University
Hofmann-related compounds based on the pillared cyano-bridged architecture, [Ni(L)Ni(CN)4]n (L = pillar organic ligands), or known as PICNICs, could be rigid or dynamic metal organic frameworks (MOF) depending on the choice of pillar organic ligands. We found that when L=4,4’-bipyridine, in addition to the 3D compound [Ni(4,4’-bipyridine)Ni(CN)4]n) (with DMSO as solvent), a 2D non-porous [Ni(CN)4Ni(C10H8N2)(NH3)2] (orthorhombic Pnnm) compound also co-existed. The 2D compound features a metal organic cyanide-bridged layered framework, while the 3D material (orthorhombic Pccn) was found to consist of a network built from extended 2-D [Ni(CN)4] layers. These layers are connected to each other via the Bpy ligands at the six-fold coordinated Ni2 site while Ni1 has a four-fold coordination environment. Powder samples of the 3D compound (without DMSO) exhibit Type-I CO2 sorption characteristics. The absence of a hysteresis loop (gating behavior) of the sorption curves indicates that it is not likely to be a flexible MOF.
9:35 AM Invited
Porous Materials Design Using Machine Learning: Lan Li1; 1Boise State University
Nanomaterials like molecular sieve, zeolites, metal-organic frameworks, and porous carbon are considered for post-combustion CO2 capture. Millions of hypothetical porous structures have been constructed. An effective approach that can effectively and quickly identify high-performance candidates with desired properties is crucial. Machine learning is a powerful approach that can quickly screen a large scale of datasets, narrow down potential candidates, and identify data patterns and trends that can guide materials development. Therefore, machine learning has been widely utilized in different segments to enhance the efficiency of carbon capture and storage. This presentation will summarize the machine learning methods commonly used in the porous materials design. Recommendations for future applications of machine learning will be also presented.
10:05 AM Break
10:25 AM Invited
Investigating Flexible Framework Materials by Combining Powder Diffraction and First-principles Calculations: Wei Zhou1; 1National Institute of Standards and Technology
Flexible framework materials are a fascinating subfamily of porous crystalline materials. The unique structural flexibility related to pore opening/closing makes them highly promising for many gas adsorption related applications. Single-crystal diffraction measurements, while highly valuable, are not always feasible in practice on these materials. In this talk, I will present our approach of combining x-ray or neutron powder diffraction and first-principles calculations to investigate flexible framework materials. Several recently studied flexible hydrogen-bonded organic frameworks and covalent organic frameworks will be discussed in detail. The insights obtained from our work provide useful guidance for the development of new flexible framework materials aiming for improved gas adsorption related performance.
10:55 AM Invited
Structure and CO2 Adsorption Sites in the Flexible Coordination Polymer NiDBM-Bpy from Density Functional Theory Calculations: Eric Cockayne1; Winnie Wong-Ng1; Andrew Allen1; 1National Institute of Standards and Technology
Bis-dibenzoylmethanato 4,4’-dipyridine nickel, or NiDBM-Bpy for short, is a flexible coordination polymer system that accommodates a variety of guest molecules [Soldatov et al., Chem. Mater. 2003, 15, 4810-4818]. Soldatov et al. have refined the structure of the NiDBM-Bpy host with chlorobenzene as a guest, but were unable to obtain significant large single-crystal samples of empty NiDBM-Bpy to determine its structure. Kauffman et al. [Angewandte Chemie 2011, 50, 10888-10892] found selective adsorption of CO2 over other light gases in this system and evidence for a phase transition upon sufficient CO2 adsorption. We use dispersion-corrected density functional theory calculations to model the structure of the empty NiDBM-Bpy, and the favored positions of CO2 at low pressures. The origin of the flexibility and the phase transition in this system is discussed in light of our results.
11:25 AM
MOF Derived Green Catalysts: Suzuki-Miyaura C–C Coupling of Aryl Chlorides and Bechamp Reduction of Nitroarenes to Amines Employing Pd@MOF and Porous Co@Carbonized MOFs as Heterogeneous and Recyclable Catalysts: Krishna Manna1; Natarajan S1; 1Indian Institute of Science
Two new isostructural inorganic coordination polymers, [M(C14H8O6)(C10H8N2)2H2O)]·(C3H7NO), (M=Co, Ni) were prepared employing 2, 5-bis(prop-2-yn-1-yloxy)terephthalic acid and 4,4´ bipyridine as ligands. The connectivity between the metal-centers and the ligands give rise to a two-dimensional layer structure, which are stacked one over the other in ABABAB··· fashion. The Co-containing compound, 1, carbonized directly to produce Co-nanoparticles, supported over highly porous carbon. The Co@C–T compounds were found to be active for the Bechamp reaction of reduction of nitroarenes to aminoarenes under solvent-free conditions. The Ni-containing compound, 2, was loaded with Pd-nanoparticles by known procedures. The Pd@2 sample found to be a good catalyst for the Suzuki-Miyaura C–C coupling of chloroarenes in ethanol at 75 °C. The present work demonstrates clean and green approach for the preparation of new heterogeneous catalysts for the reduction of nitroarenes under solvent-free conditions and especially towards activating chloro-arenes under recyclable reaction conditions employing environmentally benign ethanol.
11:45 AM
Linking Structure and Catalytic Properties of Heterogeneous and Automotive Catalysts Through High Resolution X-ray Nanotomography and Cryogenic Focused Ion Beam Microscopy in Three Dimensions: Andy Holwell1; Maadhav Kothari1; Markus Boese1; Aakash Varambhia2; Dogan Ozkaya2; 1Carl Zeiss Microscopy Llc; 2Johnson Matthey Plc
Heterogeneous catalysts are a broad class of engineered porous materials, of high surface area and surface functionalization. Complex structure-property relationships are defined by porosity, permeability, nanoparticles and adhesion. We demonstrate novel multiscale 3D microscopy approaches to imaging internal structures and simulating performance of gasoline particulate filters (GPF), polymer electrolyte fuel cells (PEFC) and metal organic frameworks (MOF). We describe X-ray microscopy techniques for 3D imaging, pore analysis, and quantification of catalytic layers on substrates. Deep learning was used for reconstruction, measurement and multiphase segmentation of GPF datasets, which were inputted into gas flow simulations relating pressure drop to performance and reactivity, using experimentally-derived conditions. X-ray nanotomography was used to simulate gas diffusion through pore networks in PEFC. Non-destructive 4D studies were enabled by time-resolved in situ experiments.Finally, novel cryogenic FIB microscopy techniques were developed for volumetric analysis and lamella preparation for nanoanalytics of MOF materials.