Article
Chemistry, Multidisciplinary
Alexander Goller, Johannes Obenauf, Winfried P. P. Kretschmer, Rhett Kempe
Summary: We reported a Coordinative Chain Transfer Polymerization catalyst for highly controlled and efficient polymerization of ethylene. The Zr catalyst demonstrated long life and temperature stability, and showed high activity with triethylaluminum as the chain transfer agent. The addition of ethylene gradually increased the chain length of the polyethylene products, and very low polydispersity was achieved with catalyst elongating alkyl chains of 60,000 or more.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Xiong Wang, Wenqian Kang, Lin Gao, Guangquan Li, Xuerong Chen, Yi Guo
Summary: In this study, nano TiO2 beads were used to modify the physical properties of POPs and achieved TiO2/POP supports with higher specific surface area and flowability, leading to improved catalytic activity. The prepared TiO2/POP catalyst showed higher ethylene polymerization activity compared to commercial metallocene catalyst, with the immobilized (n-BuCp)(2)ZrCl2/MAO@POP-7 catalyst exhibiting the highest productivity.
Article
Chemistry, Physical
Wenqian Kang, Sheng Chen, Xiong Wang, Guangquan Li, Xiaoyu Han, Minfeng Da
Summary: In this study, ionic liquid-modified porous organic polymers (IL-POPs) were successfully synthesized and used to immobilize metallocene catalysts for olefin polymerization. The prepared IL-POPs exhibited a wide range of pore characteristics, and the supported catalysts showed high activity and narrow molecular weight distribution. The resulting polyethylene had a high melting point and similar chemical composition distribution.
Article
Polymer Science
Amjad Ali, Ahmad Naveed, Tahir Rasheed, Tariq Aziz, Muhammad Imran, Ze-Kun Zhang, Muhammad Wajid Ullah, Ameer Ali Kubar, Aziz Ur Rehman, Zhiqiang Fan, Li Guo
Summary: The vinyl addition polymerization of 4-vinyl-cyclohexene (VCH) comonomers with ethylene in toluene at 50 degrees C was investigated using symmetrical metallocene catalyst combined with borate/TIBA. The obtained copolymers exhibited good solubility in conventional organic solvents, excellent thermal stability, and crystalline properties.
Article
Chemistry, Inorganic & Nuclear
Suting Xu, Yanchen Huo, Xiang Hu, Fei Wang, Li Pan, Xiaochao Shi
Summary: In this study, rare-earth metal complexes bearing tetrahydrofluorenyl ligands were synthesized and characterized. These complexes showed excellent catalytic activity for the polymerization of styrene and butadiene, resulting in diblock copolymers with highly syndiotactic polystyrene block and a 1,4-specific PBD block. The study also revealed the significant difference in reactivity ratios between butadiene and styrene, supporting the block structure of the copolymers. Morphology and mechanical properties of the selected diblock copolymer were investigated.
INORGANIC CHEMISTRY
(2023)
Article
Polymer Science
Wenhua Lin, Qiuyue Zhang, Liping Zhang, Gregory A. Solan, Yanping Ma, Xiang Hao, Wen-Hua Sun
Summary: A set of six 2-iminopyridine-nickel(II) complexes were synthesized and one of them showed high catalytic activity in ethylene polymerization, producing low molecular weight polyethylene with branch chains and unsaturated functionality.
Article
Chemistry, Multidisciplinary
Zoha H. Syed, Mohammad Rasel Mian, Roshan Patel, Haomiao Xie, Zihan Pengmei, Zhihengyu Chen, Florencia A. Son, Timothy A. Goetjen, Alon Chapovetsky, Kira M. Fahy, Fanrui Sha, Xingjie Wang, Selim Alayoglu, David M. Kaphan, Karena W. Chapman, Matthew Neurock, Laura Gagliardi, Massimiliano Delferro, Omar K. Farha
Summary: Understanding heterogeneous catalysts is a challenging pursuit due to the nonuniformity and aperiodicity of surface sites in traditionally used materials, such as sulfated metal oxides. This study focuses on sulfated metal-organic frameworks as structurally defined analogues to gain insights into the properties and behavior of heterogeneous catalysts. Through characterization techniques such as X-ray diffraction and DRIFTS, the sulfate binding motif in sulfated MOF NU-1000 is found to transition depending on hydration level, and the sulfated MOF shows heightened acidity compared to the parent MOF. The supported catalyst based on the sulfated MOF node exhibits efficacy in the activation of benzene-d(6) and toluene, with structure-activity relationships derived.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Susannah A. A. Miller, Damien Guironnet
Summary: Functionalizing inorganic particles with organic ligands is a common technique for heterogenizing organometallic catalysts. We studied the unexpected latency in catalytic activity of molecular platinum coordinated to silica nanoparticles functionalized with norbornene ligands. We found that this latency is related to ligand density, chemical structure of the norbornene, and nanoparticle topology. Additionally, we demonstrated the benefit of this latency for triggering curing of silicone elastomers.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
S. Olivia Gunther, Qingheng Lai, Todd Senecal, Rafael Huacuja, Sean Bremer, David M. Pearson, Jessica C. DeMott, Nattamai Bhuvanesh, Oleg Ozerov, Jerzy Klosin
Summary: By preparing and evaluating various carborane salts as activators, it was found that activators based on undecachloro carboranes led to highly active catalysts, while other activators were inactive under specific conditions. Polymer samples obtained from different catalysts showed similar performance, indicating that carborane anions do not influence catalyst kinetics.
Article
Chemistry, Physical
Alon Chapovetsky, Robert M. Kennedy, Ryan Witzke, Evan C. Wegener, Fulya Dogan, Prajay Patel, Magali Ferrandon, Jens Niklas, Oleg G. Poluektov, Ning Rui, Sanjaya D. Senanayake, Jose A. Rodriguez, Nestor J. Zaluzec, Lei Yu, Jianguo Wen, Christopher Johnson, Cynthia J. Jenks, A. Jeremy Kropf, Cong Liu, Massimiliano Delferro, David M. Kaphan
Summary: This article describes the application of Li-ion battery cathode and anode materials as redox non-innocent catalyst supports for the electronic tuning of a catalyst's active site. The activity of the catalyst for olefin hydrogenation was found to increase as a function of support reductive lithiation. Simulation results reveal the significant impact of surface redox states on the viability of the homolytic oxidative addition mechanism.
Article
Chemistry, Physical
Guoqiang Gan, Xinyong Li, Shiying Fan, Zhifan Yin, Liang Wang, Guohua Chen
Summary: The study successfully prepared a bifunctional ultrathin Fe-N-x-C single-atom catalysts (SACs) for both EER and ACR, recycling generated HCl as a chlorinating reagent. The Fe-N-x-C SACs exhibited excellent electrocatalytic performance for both reactions, with high selectivity for ethylene and para-chloroanisole.
Article
Polymer Science
Sung Moon Bae, Sun Mi Jeong, Jun Won Baek, Hyun Ju Lee, Hagjun Kim, Yeokwon Yoon, Sangchul Chung, Bun Yeoul Lee
Summary: The productivity of supported catalysts can be enhanced by using dinuclear metallocene complexes instead of the conventional mononuclear analogs, leading to reduced formation of large polymer particles.
EUROPEAN POLYMER JOURNAL
(2021)
Article
Chemistry, Physical
Xinjuan Li, Jiaxin Dong, Guanglei Ma, NaNa Ma, Xianbin Jia
Summary: The design of simulated enzyme catalysts with high catalytic activity, high selectivity, and water recyclability is of great research value. In this study, a star-shaped thermal responsive polymer-Ru/diamine functional intelligent chiral catalyst was synthesized using controlled atom transfer radical polymerization (ATRP). The synthesized catalyst exhibited better catalytic activity and selectivity in water, and could be recycled for multiple uses.
JOURNAL OF CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Clement G. Collins Rice, Louis J. Morris, Jean-Charles Buffet, Zoe R. Turner, Dermot O'Hare
Summary: Using a highly active permethylindenyl-phenoxy (PHENI*) titanium catalyst, high to ultra-high molecular weight ethylene-linear-alpha-olefin copolymers are efficiently synthesized under mild conditions. The system allows for the production of copolymers with a wide range of compositions and material properties through predictive alteration of reaction conditions, offering numerous possibilities for applications.
Article
Materials Science, Composites
Yan Lv, Jingjing Xia, Yang Yang, Yizhou Chen, Tianxi Liu
Summary: This study developed a novel thin-film composite nanofiltration membrane with modified nanofiber surface and an efficient filtration structure, resulting in high water flux and excellent rejection rates for ions. The use of surface mineralization and wrinkled structure provides a promising approach for the development of highly efficient nanofiltration membranes in comprehensive separation applications.
COMPOSITES COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Liqun Kang, Bolun Wang, Adam Thetford, Ke Wu, Mohsen Danaie, Qian He, Emma K. Gibson, Ling-Dong Sun, Hiroyuki Asakura, C. Richard A. Catlow, Feng Ryan Wang
Summary: The study reports an air-stable surface [bipy-Ru-II(CO)(2)Cl-2] site capable of oxidizing CO, demonstrating practical control over geometric and electronic structures of single-site catalysts at the molecular level.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Donato Decarolis, Adam H. Clark, Tommaso Pellegrinelli, Maarten Nachtegaal, Evan W. Lynch, C. Richard A. Catlow, Emma K. Gibson, Alexandre Goguet, Peter P. Wells
Summary: This study utilized operando spectroscopy to spatially profile a Pd/Al2O3 catalyst during NH3 oxidation, revealing insights into structure-activity relationships in catalysis. The results showed a direct correlation between the presence of PdNx and selectivity toward N-2, and proposed two simultaneous reaction pathways at high temperatures. These findings highlight the structural and catalytic diversity during catalysis, emphasizing the importance of understanding for improving emission control technologies like selective catalytic oxidation of NH3.
Article
Chemistry, Applied
Tommaso Pellegrinelli, Geoffrey McCullough, Roberto Caporali, Iain Murray, Veronica Celorrio, Emma K. Gibson, Christopher Hardacre, Alexandre Goguet
Summary: Hydrothermal degreening and ageing procedures were applied to a tri-metal (Pt-Pd-Rh) fully formulated lean NOx Trap catalyst to evaluate the effects of thermal stress on performance and structural properties. The size of platinum particles and ceria particles increased after ageing treatment, while a decrease in active NOx storage sites was observed. The aged sample showed a lower reductant consumption and more efficient reduction process, with a wider spread presence of NH3 and NOx slip observed during reduction due to different distributions of adsorbed species.
Article
Physics, Condensed Matter
Monik Panchal, June Callison, Vainius Skukauskas, Diego Gianolio, Giannantonio Cibin, Andrew P. E. York, Manfred E. Schuster, Timothy Hyde, Paul Collier, C. Richard A. Catlow, Emma K. Gibson
Summary: The research found that the catalytic performance of GPF samples with different ash contents varies in the reduction of substances such as CO and NO in exhaust gases. Samples with a higher ash content exhibit more severe performance degradation after aging.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Chemistry, Applied
Vainius Skukauskas, Elliot L. B. Johnson Humphrey, Iain Hitchcock, Andrew York, Joseph Kelleher, Emma K. Gibson, David J. Nelson, Ian P. Silverwood
Summary: The article introduces the method of using neutron probes to observe the progress of catalytic reactions and the recent progress and possibilities in realistic applications.
TOPICS IN CATALYSIS
(2021)
Article
Nanoscience & Nanotechnology
Puttipong Pananusorn, Araya Ruengsuk, Andrew Docker, Korawit Khamphaijun, Kitima Sirivibulkovit, Mongkol Sukwattanasinitt, Jonggol Tantirungrotechai, Phoonthawee Saetear, Taweetham Limpanuparb, Thanthapatra Bunchuay
Summary: A novel quinhydrone-type complex between pillar[5]quinone (P[5]Q) and hydroquinone (HQ) is reported, which exhibits high stability and can be used for the selective liquid-liquid extraction and recovery of HQ.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Organic
Adisorn Khanthong, Korawit Khamphaijun, Araya Ruengsuk, Andrew Docker, Taweetham Limpanupar, Jonggol Tantirungrotechai, Thanthapatra Bunchuay
Summary: The synthesis and characterization of a novel class of P[4]A[1]SMe pillar[4]arene thioarenes are reported. An oxidation-thionation strategy was used to replace a single dialkoxybenzene panel in the parent P[5]arene. H-1 NMR spectroscopic titration experiments, supported by density functional theory computational studies, revealed the starkly modulated host-guest binding properties of P[4]A[1]SMe for electron-deficient aliphatic guests.
Article
Chemistry, Physical
Thulani M. Nyathi, Mohamed I. Fadlalla, Nico Fischer, Andrew P. E. York, Ezra J. Olivier, Emma K. Gibson, Peter P. Wells, Michael Claeys
Summary: Co3O4 nanoparticles were supported on different TiO2 polymorphs and their catalytic performance in CO-PrOx was evaluated. Supporting Co3O4 on P25 resulted in the highest CO conversion to CO2 (72.7%), while rutile and anatase showed lower conversions (60.7% and 51.5% respectively). The reduction of Co3O4 was highest on P25 and lowest on anatase, with different crystal phases of Co-0 observed. Furthermore, the presence of different TiO2 polymorphs influenced the formation of undesired CH4 over Co-0 nanoparticles.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Apostolos Kordatos, Khaled Mohammed, Reza Vakili, Alexandre Goguet, Haresh Manyar, Emma Gibson, Marina Carravetta, Peter Wells, Chris-Kriton Skylaris
Summary: The formation of interstitial PdCx nanoparticles is studied through DFT calculations. Migration and diffusion mechanisms of C atoms in Pd NPs are investigated, revealing the preference for interstitial sites and limited mobility towards the NP core. The reaction energies of carbidisation vary with C-concentration, with exothermic reactions observed at low concentrations and endothermic reactions at higher concentrations, indicating the preference for surface residence of C atoms.
Article
Chemistry, Physical
Ricardo Navar, Giulia Tarantino, Owain T. Beynon, Daniele Padovan, Luca Botti, Emma K. Gibson, Peter P. Wells, Alun Owens, Simon A. Kondrat, Andrew J. Logsdail, Ceri Hammond
Summary: Sn-Beta has emerged as an advanced catalyst for sustainable chemical reactions. This study improves the preparation process of Sn-Beta through solid-state synthesis and explores the mechanism of Sn incorporation. The research finds that successful incorporation of Sn into the lattice occurs through several steps and fully oxidized Sn precursors are unsuitable for lattice incorporation.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Multidisciplinary
Korawit Khamphaijun, Phitawat Namnouad, Andrew Docker, Araya Ruengsuk, Jonggol Tantirungrotechai, Raul Diaz-Torres, David J. Harding, Thanthapatra Bunchuay
Summary: Unprecedented pillar[5]arene-isocyanide pseudorotaxane complexes are reported. By varying the alkyl chain length, [2]- or [3]pseudorotaxanes can be formed. Moreover, electron-deficient aryl isocyanides can also form inclusion complexes within the cavities of pillar[5]arenes.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Phakpoom Angpanitcharoen, Jessica Lamb, Jean-Charles Buffet, Zoe R. Turner, Dermot O'Hare
Summary: A new family of zirconocene complexes have been synthesized and characterized, showing different initiation groups have significant influence on polymerization activity, with alkyl catalysts performing better than halide catalysts. Among the studied catalysts, sMAO-meso-((3-Et)Ind(#))(2)Zr(CH2Ph)(2) exhibited the highest activity and produced HDPE with the highest molecular weight at temperatures below 70 degrees Celsius.
Article
Chemistry, Inorganic & Nuclear
Elizabeth A. Hamilton, Alexander F. R. Kilpatrick, Zoe R. Turner, Duncan A. X. Fraser, Jean-Charles Buffet, Dermot O'Hare
Summary: The synthesis and characterization of new permethylpentalene zirconium bis(amido) and permethylpentalene zirconium cyclopentadienyl mono(amido) complexes, as well as their reactivity with carbon dioxide, were reported in this study.
DALTON TRANSACTIONS
(2021)
Article
Chemistry, Inorganic & Nuclear
Zoe R. Turner, Jessica V. Lamb, Thomas P. Robinson, Dipa Mandal, Jean-Charles Buffet, Dermot O'Hare
Summary: In this study, a new family of group 4 permethylpentalene aryloxide and alkoxide complexes were synthesised and fully characterised by multinuclear NMR spectroscopy and single-crystal X-ray diffraction. Initiators 3 was found to exhibit the highest activity for the ring-opening polymerisation of l-lactide.
DALTON TRANSACTIONS
(2021)
Article
Chemistry, Multidisciplinary
Thomas J. Williams, Jessica V. Lamb, Jean-Charles Buffet, Tossapol Khamnaen, Dermot O'Hare
Summary: A family of permethylindenyl titanium constrained geometry complexes supported on solid polymethylaluminoxane (sMAO) were investigated for slurry-phase ethylene/H2 homopolymerisation and ethylene/1-hexene copolymerisation, demonstrating high 1-hexene incorporation levels and the ability to controllably tune the amount of 1-hexene incorporated into the polymer chain to produce linear low-density polyethylene (LLDPE) materials.
