A5101997241- Catalytic Processes in Materials Science
- Asymmetric Hydrogenation and Catalysis
- Luminescence and Fluorescent Materials
- Organic Electronics and Photovoltaics
- Catalysis and Oxidation Reactions
- Electrocatalysts for Energy Conversion
- Nanomaterials for catalytic reactions
- Zeolite Catalysis and Synthesis
- Spectroscopy and Quantum Chemical Studies
- Organic Light-Emitting Diodes Research
- Catalysis and Hydrodesulfurization Studies
- Ammonia Synthesis and Nitrogen Reduction
- Catalysis for Biomass Conversion
- Laser-Matter Interactions and Applications
- Spectroscopy Techniques in Biomedical and Chemical Research
- Molecular Junctions and Nanostructures
- Mesoporous Materials and Catalysis
- Photoreceptor and optogenetics research
- Polyoxometalates: Synthesis and Applications
- CO2 Reduction Techniques and Catalysts
- Machine Learning in Materials Science
- Photochromic and Fluorescence Chemistry
- Surface Chemistry and Catalysis
- Drilling and Well Engineering
- Fluid Dynamics and Mixing
University of California, Davis
2011-2024
Northeast Forestry University
2024
Wuhan Textile University
2020-2023
Kyoto University
2018-2021
Northeast Normal University
2013-2017
Nanyang Technological University
2015-2016
South China University of Technology
2010-2015
Singapore Polytechnic
2015
China University of Petroleum, East China
2015
Southeast University
2015
As good as atomic gold: Aberration-corrected scanning transmission electron microscopy images of zeolite NaY-supported mononuclear gold complexes, obtained with resolution the atoms, showed locations complexes in framework (see picture) and identified them catalytically active species for CO oxidation at 298 K 1 bar. Detailed facts importance to specialist readers are published ”Supporting Information”. Such documents peer-reviewed, but not copy-edited or typeset. They made available...
The performance of a supported catalyst is influenced by the size and structure metal species, ligands bonded to metal, support. Resolution these effects has been lacking because lack investigations catalysts with uniform systematically varied catalytic sites. We now demonstrate that for ethene hydrogenation isostructural iridium species on supports contrasting properties as (electron-donating MgO electron-withdrawing HY zeolite) can be elucidated basis molecular concepts. Spectra working...
It is more challenging to synthesize acenes with even-number fused benzene rings (AWEB) than odd-number (AWOB) because AWEB are either synthetically asymmetric or the precursors prepare very difficult obtain from commercially available sources. In this work, we employed 2,6-naphthodiyne precursor (2) as an effective synthon a large AWEB, 6,9,16,19-tetraphenyl-1.20,4.5,10.11,14.15-tetrabenzooctatwistacene (1), through simple, one-step, double [4 + 2] cycloaddition reaction. The physical...
The supramolecular packing mode of organic π-conjugated molecules in the solid state plays a crucial role determination resulting material properties and functionalities. Control understanding individual building blocks constitute an important step toward optoelectronic biomedicine. In this work, we have designed synthesized series bis(pyrene) derivatives, i.e., BP1–BP4 with 1,3-dicarbonyl, pyridine-2,6-dicarbonyl, oxaloyl benzene-1,4-dicarbonyl as linkers, respectively. solution, all...
Agglomerative sintering of an atomically dispersed, zeolite Y-supported catalyst, Ir1/zeolite Y, formed initially from the well-characterized precatalyst [Ir(C2H4)2]/zeolite Y and in presence liquid-phase reactants, was monitored over three cycles 3800 turnovers (TTOs) cyclohexene hydrogenation at 72 °C. The catalyst evolved sintered during each cycle, even relatively mild temperature °C plus H2 reactants cyclohexane solvent. Post catalysis, resultant characterized by extended X-ray...
Propane dehydrogenation over perfect Ga2O3(100) was studied in detail by periodic density functional theory (DFT) calculations. It found that the initial C−H bond activation mainly follows a radical mechanism two-coordinated surface oxygen site (O(2)) abstracts hydrogen atom from propane with formation of propyl and hydroxyl group (O(2)H). Physically adsorbed can easily form propoxide or propylgallium intermediate. Subsequently, propene is formed second H abstraction propyl, propoxide, Ga...
Zeolite- and MgO-supported mononuclear iridium diethene complexes were formed by the reaction of Ir(C2H4)2(acac) (acac = acetylacetonate, C5H7O2–) with each support. Changes in ligand environment supported characterized infrared, X-ray absorption near edge structure, extended fine structure spectroscopies as various mixtures H2, C2H4, CO flowed over samples. In contrast to nonuniform metal anchored oxides, our zeolite-supported highly uniform, allowing precise determinations chemistry,...
The formation of iridium clusters from supported mononuclear complexes in H(2) at 300 K and 1 bar was investigated by spectroscopy atomic-resolution scanning transmission electron microscopy. first steps cluster zeolite-supported Ir(C(2)H(4))(2) are triggered the activation hydride, accompanied breaking iridium-support bonds. This reactivity can be controlled choice ligands on iridium, which include support.
Using aberration-corrected scanning transmission electron microscopy (STEM), we imaged iridium atoms in isolated complexes the one-dimensional nonintersecting 14-ring channels of zeolite SSZ-53. STEM allows tracking movement channels, demonstrating interaction with framework (channel confinement) and providing a direct visualization initial steps metal nanocluster formation. The results demonstrate how can be used to help design improved catalysts by identifying catalytic sites observing...
This work addresses the question of what is true catalyst when beginning with a site-isolated, atomically dispersed precatalyst for prototype catalytic reaction cyclohexene hydrogenation in presence cyclohexane solvent: nature zeolite-supported, [Ir(C2H4)2]/zeolite Y retained, or are possible alternatives including Ir4 subnanometer clusters larger, Ir(0)n, nanoparticles actual catalyst? Herein we report (a) kinetics reaction; (b) physical characterizations used catalyst, extended X-ray...
The oxidative dehydrogenation (ODH) of propane to propene over a vanadium-based catalyst suffers from side reactions further and complete oxidations other intermediates, which limit the yield propene. These oxidation are also referred as deep ODH. In this paper, we present comprehensive study in ODH V2O5(001) surface using periodic density functional theory method. It is shown that main source byproducts originates reaction intermediate isopropoxide, leading acetone following Thorough more...
Zeolite Hβ- and γ-Al(2)O(3)-supported mononuclear iridium complexes were synthesized by the reaction of Ir(C(2)H(4))(2)(acac) (acac is acetylacetonate) with each supports. The characterization surface species extended X-ray absorption fine structure (EXAFS) infrared (IR) spectroscopies demonstrated removal acac ligands during chemisorption, leading to formation essentially isostructural Ir(C(2)H(4))(2) anchored support two Ir-O(support) bonds. Atomic-resolution aberration-corrected scanning...
Goldatomen auf der Spur: Bilder von einkernigen Goldkomplexen Zeolith-NaY-Trägermaterialien, die mit aberrationskorrigierter Rasterelektronenmikroskopie erhalten wurden, zeigen bei atomarer Auflösung Goldatome, wo sich Goldkomplexe im Zeolithgerüst befinden (siehe Bild), und belegen, dass sie katalytisch aktiven Spezies für Oxidation CO 298 K 1 bar sind. Detailed facts of importance to specialist readers are published as "Supporting Information". Such documents peer-reviewed, but not...
Abstract Organic redox‐active polymers are promising electrode alternatives to Li‐ion batteries using transition‐metal resources. Such metal‐free materials suffer realistically from low electronic conductivities and insufficient utilization of active sites. Herein, thermally imidized polyimides synthesized by polycondensation between 2,6‐diaminoanthraquinone (DAAQ) anhydrides. A quinone‐containing polyimide (PMAQ) derived pyromellitic dianhydride DAAQ is found exhibit the highest capacity...
A longstanding challenge in catalysis by noble metals has been to understand the origin of enhancements rates hydrogen transfer that result from bonding oxygen near metal sites. We investigated structurally well-defined catalysts consisting supported tetrairidium carbonyl clusters with single-atom (apical iridium) catalytic sites for ethylene hydrogenation. Reaction and H2 followed O2 led onset activity as a terminal CO ligand at each apical Ir atom was removed bridging dioxygen ligands...
Oxidative dehydrogenation (ODH) of ethane over the V2O5 (001) surface has been carried out using periodic density functional theory (DFT) calculations. We show that first C−H bond activation leading to an ethoxide intermediate is rate-limiting step reaction. The most feasible pathway for predicted take place at O(1) (VO) site, with energy 35.1 kcal/mol. O(2) (V−O−V) site less active activation, barrier 37.6 However, exhibits much lower selectivity ethene formation than because side reaction...
The rational design of a novel phenoxazine-based D–B–A<sub>2</sub>–B–D TADF candidate with smaller Δ<italic>E</italic><sub>ST</sub> values and higher carrier transport.
By use of the precursor Ir(CO)2(acac) (acac is acetylacetonate), a ship-in-a-bottle synthesis was used to prepare Ir6(CO)16 and, by decarbonylation, clusters well approximated as Ir6 in supercages zeolite NaY. The samples were characterized infrared and extended X-ray absorption fine structure (EXAFS) spectroscopies imaged aberration-corrected scanning transmission electron microscopy with high-dose beam (∼108 e–/Ǻ2, 200 kV), catalyst performance turnover frequencies for ethene hydrogenation...