Article
Chemistry, Multidisciplinary
Min Hu, Chao Wang, Yueying Chu, Qiang Wang, Shenhui Li, Jun Xu, Feng Deng
Summary: Understanding the acid sites on zeolites is crucial for establishing the relationship between catalyst structure and activity, as well as exploring their potential applications in catalysis. In this study, we identified active Lewis acid sites on ZSM-5 zeolites and found their important role in methanol reactions through experimental and theoretical investigations.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Chao Wang, Yueying Chu, Min Hu, Wenjin Cai, Qiang Wang, Guodong Qi, Shenhui Li, Jun Xu, Feng Deng
Summary: The study demonstrates that electron-deficient cyclopentenyl cations in ZSM-5 zeolite can capture compounds produced in the MTO reaction through noncovalent interactions, including alkanes, methanol, and olefins. These carbocation-induced noncovalent interactions modulate the product selectivity of the hydrocarbon pool reaction. The research identified intermolecular spatial proximities/interactions through two-dimensional C-13-C-13 correlation solid-state NMR spectroscopy.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Applied
Darren H. Brouwer, Alexa L. White
Summary: Solid-state nuclear magnetic resonance (SSNMR) spectroscopy is a valuable technique for characterizing the structural features of zeolites. This paper reports a comprehensive collection of 73 P-31 SSNMR spectra of aluminophosphate zeolites, investigating the relationship between the geometry around the P sites and the P-31 chemical shifts.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Review
Multidisciplinary Sciences
Weiyu Wang, Jun Xu, Feng Deng
Summary: This review examines the recent progress in the study of zeolites and relevant catalytic reactions using solid-state NMR methods to explore framework structures, catalytically active sites, and intermolecular interactions. It also discusses the application of solid-state NMR technique in understanding the mechanistic aspects of zeolite-catalyzed reactions, such as methanol and ethanol conversions.
NATIONAL SCIENCE REVIEW
(2022)
Review
Chemistry, Physical
Sharon E. Ashbrook, Russell Morris, Cameron M. Rice
Summary: This article discusses the use of solid-state NMR experiments in studying the development of new types of zeolites, as well as the application of 17O NMR spectroscopy in probing reactivity and understanding the behavior of zeolites in the presence of liquid water.
CURRENT OPINION IN COLLOID & INTERFACE SCIENCE
(2022)
Article
Chemistry, Inorganic & Nuclear
Eddy Dib, Edwin B. Clatworthy, Louwanda Lakiss, Valerie Ruaux, Svetlana Mintova
Summary: Deuterium solid-state MAS NMR spectroscopy is used to identify silanols and Bronsted acid sites in zeolites. The study shows a clear spectroscopic difference between zeolites with only silanols or both silanols and Bronsted acid sites compared to static H-2 NMR spectroscopic studies. This study highlights the versatility of solid-state MAS NMR spectroscopy and its synergy with IR spectroscopy in providing important information on zeolite properties.
INORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Multidisciplinary
Wei Gao, Qiang Wang, Guodong Qi, Jiawei Liang, Chao Wang, Jun Xu, Feng Deng
Summary: By using 1D Mo-95 NMR and 2D H-1-Mo-95 heteronuclear correlation solid-state NMR spectroscopy, the active ensembles in the confined channels of Mo/ZSM-5 zeolite during the MDA reaction were observed. Two kinds of MoOxCy species were identified, with MoOxCy-II showing higher activity for methane activation and benzene formation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Inorganic & Nuclear
Samantha E. Russell, Fanny N. Costa, Maria Diaz-Lopez, Russell E. Morris
Summary: An in situ pair distribution function study was conducted to assess the reassembly process of three IM-12 (UTL) intermediate materials into fully connected materials. The results showed that there is a greater level of atomic change at higher temperatures for the reassembly of the fully disconnected intermediate, IPC-1P, compared to the two partially connected intermediates, IPC-2P and IPC-6P.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Multidisciplinary
Chao Wang, Xingling Zhao, Min Hu, Guodong Qi, Qiang Wang, Shenhui Li, Jun Xu, Feng Deng
Summary: This study reveals that cyclopentenyl cations formed on Ga/ZSM-5 zeolite act as active intermediates during propane aromatization, and the autocatalysis of propane to aromatics plays a significant role in the induction period, highlighting a dominant hydrocarbon pool process in propane aromatization.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Benedikt Soeldner, Kristof Grohe, Peter Neidig, Jelena Auch, Sebastian Blach, Alexander Klein, Suresh K. Vasa, Lars V. Schaefer, Rasmus Linser
Summary: Understanding macromolecular function, interactions, and stability requires detailed assessment of conformational ensembles. Limited by the qualitative or low abundance of solid-state nuclear magnetic resonance internuclear distance information, accurately elucidating the spatial dynamics of solid proteins at physiological temperatures is challenging. However, this study demonstrates unprecedented access to abundant proton-proton internuclear distances, enabling accurate molecular dynamics simulations and providing atomic-level spatial details of conformational dynamics in various biomolecular systems.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Kavyasripriya K. Samudrala, Winn Huynh, Rick W. Dorn, Aaron J. Rossini, Matthew P. Conley
Summary: This study discovers an effective approach to prepare aluminum-silicon oxide catalysts with well-defined structures. Through experimental and theoretical calculations, it is demonstrated that the catalyst exhibits strong Lewis acidity and can react with organometallic compounds.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Wei Gao, Guodong Qi, Qiang Wang, Weiyu Wang, Shenhui Li, Ivan Hung, Zhehong Gan, Jun Xu, Feng Deng
Summary: This study identified proximate dual active sites on Mo/ZSM-5 catalyst, revealing the crucial role of spatial interaction between Bronsted acid sites and Mo species in methane conversion and aromatics formation. The evolution of olefins and aromatics in Mo/ZSM-5 channels was monitored, showing the intermediate role of olefins in the hydrocarbon pool process during the MDA reaction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Review
Chemistry, Physical
Ekaterina V. Pokochueva, Dudari B. Burueva, Oleg G. Salnikov, Igor V. Koptyug
Summary: HET-PHIP has attracted significant research attention in recent years, showing major prospects for applications in biomedical MRI and industrial catalytic studies, despite the current need for further improvement in NMR signal enhancements.
Article
Chemistry, Multidisciplinary
Jiaxin Gao, Rick W. Dorn, Guillaume P. Laurent, Frederic A. Perras, Aaron J. Rossini, Matthew P. Conley
Summary: The silylium-like surface species [(Pr3Si)-Pr-i]-[(O-F)(3)Al-OSi )] activates (N boolean AND N)Pd(CH3)Cl by chloride ion abstraction to form [(N boolean AND N)Pd-CH3][((RO)-O-F)(3)Al-OSi )]. This activation shows similar reactivity patterns as (N boolean AND N)Pd(CH3)Cl activated with Na[B(Ar-F)(4)]. In addition, this activated species can catalyze the polymerization of ethylene and copolymerize with methyl acrylate.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Energy & Fuels
Francesco Panattoni, Jonathan Mitchell, Edmund J. Fordham, Ravinath Kausik, Clare P. Grey, Pieter C. M. M. Magusin
Summary: The study utilized high-field, solid-state NMR methods to analyze kerogen isolates of different maturity levels, finding that the aromatic/aliphatic ratio of kerogen increases with maturity. This increase in ratio is reflected in the H-1 MAS NMR spectra by the intensity ratio of aliphatic-to-aromatic signals, suggesting a decrease in kerogen proton density during maturation.
Article
Chemistry, Multidisciplinary
Christian Schroeder, Stacey Zones, Michael Ryan Hansen, Hubert Koller
Summary: The zeolite catalyst SSZ-42 exhibits a high abundance of hydrogen-bonded Bronsted acid sites, with the classification and diversity of hydrogen bonding affecting chemical shifts. The alignment of oxygen atoms is expected to impact their role in catalytic reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Christian Schroeder, Christopher M. Lew, Stacey I. Zones, Hubert Koller
Summary: The borosilicate zeolites can be converted to aluminosilicates through reaction with aluminum nitrate solution. The process of removing boron atoms is inhibited, possibly due to the Lewis acidic nature of aluminum ions. The positions of aluminum in the crystal structures were determined through computational and experimental methods, and it was found that aluminum insertion occurs at the boron sites. This approach can be used to create aluminosilicate zeolite catalysts with ordered active sites.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Philipp Lenz, Ryo Oshimizu, Sina Klabunde, Constantin G. Daniliuc, Christian Mueck-Lichtenfeld, Jonas C. Tendyck, Tatsuya Mori, Werner Uhl, Michael Ryan Hansen, Hellmut Eckert, Shigehiro Yamaguchi, Armido Studer
Summary: This article presents a new type of oxy-borylenes as photoreductants. Experimental results demonstrate that these oxy-borylenes can exhibit strong reducing capability under visible light, making them suitable for various reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Stefan O. Kilian, Bjoern Wankmiller, Anna Margarete Sybrecht, Jonas Twellmann, Michael Ryan Hansen, Hartmut Wiggers
Summary: This study investigates the conversion mechanism of silicon-rich silicon nitride (SiNx) as an anode material in lithium-ion batteries. It was found that the structure of the material after conversion is best described as an amorphous solid solution. Additionally, the buffer matrix of silicon-rich silicon nitride shows improved rate capability due to higher ionic conductivity and better dispersion of silicon clusters.
ADVANCED MATERIALS INTERFACES
(2022)
Article
Crystallography
Maximilian Kai Reimann, Steffen Klenner, Josef Maximilian Gerdes, Michael Ryan Hansen, Rainer Poettgen
Summary: Magnesium-rich intermetallic compounds with different rare earth and alkaline earth metals were successfully synthesized and characterized for their structures and magnetic properties, revealing significant differences in behavior. This study provides unique insights into rare earth and alkaline earth alloy systems.
ZEITSCHRIFT FUR KRISTALLOGRAPHIE-CRYSTALLINE MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Thomas Defize, Miloud Bouyahyi, Artur Rozanski, Lanti Yang, Bhaskar Patham, Teun Sweere, Sebastian Hochstadt, Michael Ryan Hansen, Katrien Bernaerts, Lidia Jasinska-Walc, Rob Duchateau
Summary: This study successfully produced retortable and well-defined polypropylene nanoporous films by introducing amphiphilic graft copolymer precursors. Functional mesoporous iPP-based films were fabricated by selectively degrading the polyester blocks of the copolymers. The structure and morphology of the films were studied using various techniques, and their potential for ultrafiltration membranes and water purification applications were evaluated.
ACS APPLIED POLYMER MATERIALS
(2022)
Article
Materials Science, Ceramics
Mehrnoosh Ghanad, Negar Akrami, Philipp Keil, Henrik Bradtmueller, Michael Ryan Hansen, Jalil Vahdati Khaki, Sahar Mollazadeh Beidokhti
Summary: Considerable progress has been made in designing boron-containing bioglasses for soft tissue regeneration using low-cost solution combustion synthesis. The resulting borate-based glasses exhibit highly porous microstructures and absence of crystalline impurity phases. The synthesis parameters can be fine-tuned to produce 1393-B3 glass powders with tailored physical properties.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Renato Grigolon Capelo, Josef Maximilian Gerdes, Ulrich Rehfuss, Lais Dantas Silva, Michael Ryan Hansen, Leo van Wuellen, Hellmut Eckert, Danilo Manzani
Summary: This study reports the preparation, optical, and structural characterization of a new fluoride-phosphotellurite glass, which possesses high thermal stability and network connectivity, making it suitable for optoelectronics and photonic devices applications.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Physical
Christian Schroeder, Michael Ryan Hansen, Hubert Koller
Summary: The interaction between Bri nsted acid sites, AlOH groups, and residual NH4+ cations in zeolites mordenite and ferrierite was investigated. High temperatures are required to eliminate NH4+. NMR data reveal NH4+ cations primarily in the vicinity of BAS and other NH4+ in mordenite, while AlOH groups in ferrierite.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Ya-Fan Chen, Christian Schroeder, Christopher M. Lew, Stacey I. Zones, Hubert Koller, Marek Sierka
Summary: In this study, the structure and formation mechanism of silanol dyads in SSZ-55 zeolite were investigated using computational methods. It was found that silanol dyads are commonly present at vacancies and the vacancy density affects the relaxation of the zeolite framework.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Johannes Hartel, Ananya Banik, Josef Maximilian Gerdes, Bjoern Wankmiller, Bianca Helm, Cheng Li, Marvin A. Kraft, Michael Ryan Hansen, Wolfgang G. Zeier
Summary: To develop solid-state batteries with high power and energy densities, solid electrolytes with fast Li+ transport are required. The selenophosphate-based lithium argyrodites Li6-x PSe5-x Br1+x (0 <= x <= 0.2) exhibit high ionic conductivities up to 8.5 mS cm-1, achieved by better interconnection of Li+ cages and additional Li+ sites. However, these selenophosphate-based lithium argyrodites are not suitable for lithium nickel cobalt manganese oxide-based solid-state batteries due to severe degradation upon charging. The work expands understanding of the structure-transport relationship in Li+ conducting argyrodites and emphasizes the importance of considering chemical and electrochemical stability of solid electrolytes when developing fast Li+ conductors.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
Christopher M. Lew, Dan Xie, Kurt O. Jensen, Christian Schroeder, Jonas Blaser, Hubert Koller, Stacey I. Zones
Summary: SSZ-82 (SEW) is a zeolite with a 12 x 10 membered ring structure and intersecting pore channels of different dimensions, offering intriguing catalytic possibilities. Previously, SSZ-82 could only be directly synthesized as a borosilicate. However, this study demonstrates that the borosilicate material can be used as seeds to synthesize an aluminosilicate product, Al-SSZ-82, through interzeolite conversion using FAU zeolite as the parent zeolite and B-SSZ-82 as seeds. The use of SSZ-82 seeds, organic structure-directing agent, Na+, and total OH- were all found to be important for the successful conversion to SSZ-82, and the conversion rate was influenced by the surface area and heteroatom of the SSZ-82 seeds.
CHEMISTRY OF MATERIALS
(2023)
