jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Al-Amin | G. Venkataprasad | Seung Joo Jang | Jeong‐Wook Oh | Tae Hyun Kim
Source: Nanomaterials (article, 2024-04-25)
Field: Chemistry — Analytical Chemistry

A MOF-Templated Double-Shelled Co3O4/NiCo2O4 Nanocomposite for Electrochemical Detection of Alfuzosin We developed a novel electrochemical sensor for the detection of alfuzosin (AFZ), a drug used to treat benign prostatic hyperplasia, using a double-shelled Co<sub>3</sub>O<sub>4</sub>/NiCo<sub>2</sub>O<sub>4</sub> nanocomposite-modified electrode. The nanocomposites were synthesized using a template-assisted approach, with zeolitic imidazole framework-67 (ZIF-67) as the sacrificial template, involving the formation of uniform ZIF-67/Ni-Co layered double hydroxide (LDH) hollow structures followed by calcination to achieve the final nanocomposite. The nanocomposite was characterized by various techniques and showed high porosity, large surface area, and good conductivity. The nanocomposite-modified electrode exhibited excellent electrocatalytic activity towards AFZ oxidation, with a wide linear range of 5-180 µM and a low limit of detection of 1.37 µM. The sensor also demonstrated good repeatability, reproducibility, and stability selectivity in the presence of common interfering substances. The sensor was successfully applied to determine the AFZ in pharmaceutical tablets and human serum samples, with satisfactory recoveries. Our results suggest that the double-shelled Co<sub>3</sub>O<sub>4</sub>/NiCo<sub>2</sub>O<sub>4</sub> nanocomposite is a promising material for the fabrication of electrochemical sensors for AFZ detection. Alfuzosin ; Nanocomposite ; Materials science ; Electrochemistry ; Hyperplasia ; Electrochemical gas sensor ; Chemical engineering ; Nanotechnology ; Medicine ; Electrode ; Chemistry ; Internal medicine ; Prostate Analytical chemistry methods development ; Pharmacological Effects and Assays ; Mass Spectrometry Techniques and Applications
Authors: Ling Qin | Ying‐Xin Zhao | Qiang Liu | Jin‐Long An | H.G Wang | Maofeng Zhang | Chengwu Shi | He‐Gen Zheng
Source: Materials Chemistry Frontiers (article, 2024-01-01)
Field: Chemistry — Inorganic Chemistry

Tuning the organic ligands to optimize the nitrogen reduction performance of Co(<scp>ii</scp>) or Ni(<scp>ii</scp>)-based MOFs The electrocatalytic nitrogen reduction to NH 3 performance of five Co(Ni)-MOFs with a similar structure can be optimized significantly by adjusting the functional block of the pyridine-bridging ligands. Reduction (mathematics) ; Nitrogen ; Metal-organic framework ; Materials science ; Inorganic chemistry ; Chemistry ; Chemical engineering ; Organic chemistry Metal-Organic Frameworks: Synthesis and Applications ; Catalytic Processes in Materials Science ; Advanced Photocatalysis Techniques
Authors: Bárbara Casteleiro | Talita de Francesco | J. M. G. Martinho | Arnaud Favier | Marie‐Thérèse Charreyre | Matthew G. Moffitt | José Paulo S. Farinha
Source: Langmuir (article, 2024-01-09)
Field: Materials Science — Materials Chemistry

NIR-Emitting Gold Nanoclusters Encapsulated in PS-<i>b</i>-PEG Polymer Micelles Gold nanoclusters (AuNCs) are an emerging type of luminescent probe, featuring good biocompatibility, high photostability, and large Stoke shifts. Their lack of colloidal stability is, however, a drawback for many applications. Here, we report the stabilization of AuNCs emitting in the NIR by a thiol-terminated polystyrene chain (<i>M</i><sub>n</sub> = 5000 g mol<sup>-1</sup>). The optical properties of this nanocomposite remain invariant for 2 years in THF. To use the PS<sub>5k</sub>-AuNCs in an aqueous environment, these were encapsulated into polymer micelles using a polystyrene-<i>b</i>-poly(ethylene glycol) copolymer. The resulting hierarchical constructs, with diameters of ca. 125 to 215 nm, have promising properties for applications as luminescent probes such as contrast agents for biomedical imaging. Nanoclusters ; Biocompatibility ; Polystyrene ; Copolymer ; Micelle ; Ethylene glycol ; Polymer ; Luminescence ; Materials science ; Aqueous solution ; Nanocomposite ; Chemical engineering ; Nanotechnology ; Colloidal gold ; Polymer chemistry ; Nanoparticle ; Chemistry ; Organic chemistry Nanocluster Synthesis and Applications ; Gold and Silver Nanoparticles Synthesis and Applications ; Advanced Nanomaterials in Catalysis
Authors: Hao‐Yi Huang | Bai‐Hao Ren | Min Xie | Yu‐Ting Huang | Kun Li | Zhongzheng Cai | Xiao‐Bing Lu | Jian‐Bo Zhu
Source: Angewandte Chemie International Edition (article, 2024-12-23)
Field: Materials Science — Biomaterials

Access to Polyhydroxyalkanoates with Diverse Syndiotacticity via Polymerization by Spiro‐Salen Complexes and Insights into the Stereocontrol Mechanism Polyhydroxyalkanoates (PHAs) have attracted broad interest as promising sustainable materials to address plastic pollution and resource scarcity. However, the chemical synthesis of stereoregular PHAs via ring-opening polymerization (ROP) has long been an elusive endeavor. In this contribution, we exploited a robust spiro-salen yttrium complex (Y3) as the catalyst to successfully prepare syndiotactic PHAs with diverse pendent groups. Simply altering the ratio of enantiomeric catalysts allowed to access of PHAs with diverse syndiotacticity (P<sub>r</sub>=0.5-0.99, from sticky oil to tough materials), delivering tunable thermal properties (glass transition temperature, T<sub>g</sub> from -52 to 70 °C and melting transition temperature, T<sub>m</sub> from 38 to 223 °C). A combined experimental and computational study suggested a polymeric exchange mechanism could boost the polymerization activity and control the syndioselectivity. Mechanism (biology) ; Polyhydroxyalkanoates ; Polymerization ; Chemistry ; Combinatorial chemistry ; Polymer ; Organic chemistry ; Biology ; Philosophy ; Genetics ; Bacteria biodegradable polymer synthesis and properties ; Organometallic Complex Synthesis and Catalysis ; Synthetic Organic Chemistry Methods
Authors: Biplab Biswas | Anjila I. Siddiqui | Mithun Chandra Majee | Swadhin Kumar Saha | Biswajit Mondal | Rajat Saha | Carlos J. Gómez‐García
Source: Inorganic Chemistry (article, 2024-03-25)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Heptanuclear Mixed-Valence Co<sub>4</sub><sup>III</sup>Co<sub>3</sub><sup>II</sup> Molecular Wheel─A Molecular Analogue of Layered Double Hydroxides with Single-Molecule Magnet Behavior and Electrocatalytic Activity for Hydrogen Evolution Reactions We present a bifunctional heptanuclear cobalt(II)/cobalt(III) molecular complex formulated as [Co<sub>7</sub>(μ<sub>3</sub>-OH)<sub>4</sub>(H<sub>2</sub>L<sup>1</sup>)<sub>2</sub>(HL<sup>2</sup>)<sub>2</sub>](NO<sub>3</sub>)<sub>6</sub>·6H<sub>2</sub>O (<b>1</b>) (where H<sub>5</sub>L<sup>1</sup> is 2,2'-(((1E,1'E)-((2-hydroxy-5-methyl-1,3-phenylene)bis(methanylylidene))bis(azanylylidene))bis(propane-1,3-diol)) and H<sub>2</sub>L<sup>2</sup> is 2-amino-1,3-propanediol). Compound <b>1</b> has been characterized by single-crystal X-ray diffraction analysis along with other spectral and magnetic measurements. Structural analysis indicates that <b>1</b> contains a mixed-valence Co<sub>7</sub> cluster where a central Co(II) ion is connected to six different Co centers (four Co<sup>III</sup> and two Co<sup>II</sup> ions) by four μ<sub>3</sub>-OH groups, giving rise to a planar heptanuclear cluster that resembles a molecular fragment of a layered double hydroxide (LDH). Two triply deprotonated (H<sub>2</sub>L<sup>1</sup>)<sup>3-</sup> ligands form the outer side of the cluster while two singly deprotonated (HL<sup>2</sup>)<sup>-</sup> ligands are located at the top and bottom of the central heptanuclear core. Variable temperature magnetic measurements indicate the presence of weak ferromagnetic Co<sup>II</sup>···Co<sup>II</sup> interactions (<i>J</i> = 3.53(6) cm<sup>-1</sup>) within the linear trinuclear Co<sup>II</sup> cluster. AC susceptibility measurements show that <b>1</b> is a field-induced single-molecule magnet (SMM) with τ<sub>0</sub> = 8.2(7) × 10<sup>-7</sup> s and <i>U</i><sub>eff</sub> = 11.3(4) K. The electrocatalytic hydrogen evolution reaction (HER) activity of <b>1</b> in homogeneous phase shows an overpotential of 455 mV, with a Faradaic efficiency of 81% and a TOF of 8.97 × 10<sup>4</sup> μmol H<sub>2</sub> h<sup>-1</sup> mol<sup>-1</sup>. Chemistry ; Crystallography ; Deprotonation ; Molecule ; Valence (chemistry) ; Cluster (spacecraft) ; Cobalt ; Hydroxide ; Stereochemistry ; Ion ; Inorganic chemistry Magnetism in coordination complexes ; Metalloenzymes and iron-sulfur proteins ; Nanocluster Synthesis and Applications
Authors: Gianluca Bartolini Torres | Smiljana Stefanovic | Bo Li | Andreas Heise
Source: ACS Applied Polymer Materials (article, 2024-09-16)
Field: Materials Science — Polymers and Plastics

Digital Light Processing (DLP) 3D Printing of Caprolactone Copolymers with Tailored Properties through Crystallinity Digital light processing (DLP) 3D printing has shown great advantages such as high resolution in the fabrication of 3D objects toward a range of applications. Despite the rapid development of photocurable materials for DLP printing, tailoring properties to meet the specific demands for various applications remains challenging. Herein, we introduce copolymers of caprolactone and allyl caprolactone offering built-in functionality for thiol-ene photochemistry, thereby omitting the need for postfunctionalization. A crystalline block copolymer and an amorphous statistical copolymer were synthesized with the same comonomer composition and molecular weight. Thio-ene photocuring with a tetrafunctional thiol cross-linker was studied at different thiol to double-bond ratios for the copolymers and their blends. All formulations undergo rapid photocuring within several seconds of irradiation with slightly higher gel fractions observed for the statistical copolymer over the block copolymer under the same conditions, suggesting a somewhat higher cross-link density. Thermal properties of the networks were dependent on the presence of the semicrystalline block copolymer, where higher melting enthalpies were reached at higher block copolymer content. Similarly, crystallinity was found to be the main contributor to the mechanical properties. For a comparable composition, the modulus of a block copolymer network was found to be 31 times higher than that of the statistical copolymer network (27.7 vs 0.89 MPa). Intermediate moduli could be obtained by blending the two copolymers. DLP-printed scaffolds from these copolymers retained their thermal properties, therefore offering an efficient approach to tailoring mechanical properties, through crystallinity. Moreover, the printed scaffold displayed shape memory properties as the first example of poly(carprolactone) (PCL) copolymers in DLP printing. These materials are readily synthesized, offer fast and high-resolution 3D printing, and are degradable and cell compatible. They offer a straightforward approach to tailoring properties of PCL-based biomaterials and devices. Crystallinity ; Digital Light Processing ; Caprolactone ; Copolymer ; Materials science ; 3D printing ; Polymer science ; Computer science ; Composite material ; Polymer ; Artificial intelligence Polymer composites and self-healing ; Additive Manufacturing and 3D Printing Technologies ; Photopolymerization techniques and applications
Authors: José Catalán‐Toledo | Jamila Djafari | Marta Mas‐Torrent | Núria Crivillers
Source: ACS Applied Nano Materials (article, 2024-02-23)
Field: Chemistry — Electrochemistry

Redox-Active Au Nanoparticles Self-Assembled at Liquid–Liquid Interface via C–Au Functionalization for Dye Degradation Electrocatalysis This work presents the synthesis of poly(vinylpyrrolidone)-stabilized gold nanoparticles (Au NPs) and their subsequent functionalization with molecules bearing terminal alkynes. The ligand exchange occurs at the liquid–liquid interface (LLI), resulting in the formation of Au NPs stabilized through the covalent C–Au functionalization. Simultaneously, structured composite films are formed, driven by the self-assembly of the Au NPs supported by the polymer. A comparative analysis involving three distinct alkyne-terminated derivatives reveals that film formation is favored when the ligand includes an aromatic unit such as in a ferrocenyl-stilbene derivative. The LLI films can be easily transferred to solid a support for their characterization. Additionally, it is demonstrated that these films serve as a potential electrocatalytic platform. As a proof of concept, we demonstrate that the electrochemically active ferrocene-based Au NPs films can efficiently remove methylene blue via an electro-Fenton-like reaction, surpassing the efficiency of the non-redox phenylacetylene Au NP films. Electrocatalyst ; Surface modification ; Redox ; Degradation (telecommunications) ; Nanoparticle ; Chemistry ; Chemical engineering ; Materials science ; Nanotechnology ; Photochemistry ; Electrochemistry ; Inorganic chemistry ; Electrode ; Computer science ; Physical chemistry Electrochemical Analysis and Applications ; Electrocatalysts for Energy Conversion ; Gold and Silver Nanoparticles Synthesis and Applications
Authors: Soonhyoung Kwon | Estefanía Bello‐Jurado | Evgeniia Ikonnikova | Hwajun Lee | Daniel Schwalbe‐Koda | Avelino Corma | Tom Willhammar | Elsa Olivetti | Rafael Gómez‐Bombarelli | Manuel Moliner | Yuriy Román‐Leshkov
Source: ACS Applied Materials & Interfaces (article, 2024-03-13)
Field: Chemistry — Inorganic Chemistry

One-Pot Synthesis of CHA/ERI-Type Zeolite Intergrowth from a Single Multiselective Organic Structure-Directing Agent We report the one-pot synthesis of a chabazite (CHA)/erionite (ERI)-type zeolite intergrowth structure characterized by adjustable extents of intergrowth enrichment and Si/Al molar ratios. This method utilizes readily synthesizable 6-azaspiro[5.6]dodecan-6-ium as the exclusive organic structure-directing agent (OSDA) within a potassium-dominant environment. High-throughput simulations were used to accurately determine the templating energy and molecular shape, facilitating the selection of an optimally biselective OSDA from among thousands of prospective candidates. The coexistence of the crystal phases, forming a distinct structure comprising disk-like CHA regions bridged by ERI-rich pillars, was corroborated via rigorous powder X-ray diffraction and integrated differential-phase contrast scanning transmission electron microscopy (iDPC S/TEM) analyses. iDPC S/TEM imaging further revealed the presence of single offretite layers dispersed within the ERI phase. The ratio of crystal phases between CHA and ERI in this type of intergrowth could be varied systematically by changing both the OSDA/Si and K/Si ratios. Two intergrown zeolite samples with different Si/Al molar ratios were tested for the selective catalytic reduction (SCR) of NO<sub><i>x</i></sub> with NH<sub>3</sub>, showing competitive catalytic performance and hydrothermal stability compared to that of the industry-standard commercial NH<sub>3</sub>-SCR catalyst, Cu-SSZ-13, prevalent in automotive applications. Collectively, this work underscores the potential of our approach for the synthesis and optimization of adjustable intergrown zeolite structures, offering competitive alternatives for key industrial processes. Zeolite ; Materials science ; Chabazite ; Catalysis ; Chemical engineering ; Hydrothermal circulation ; Phase (matter) ; Hydrothermal synthesis ; Powder diffraction ; Nanotechnology ; Crystallography ; Organic chemistry ; Chemistry Zeolite Catalysis and Synthesis ; Metal-Organic Frameworks: Synthesis and Applications ; Ammonia Synthesis and Nitrogen Reduction
Authors: Nicolò Tampellini | Brandon Q. Mercado | Scott J. Miller
Source: Chemistry - A European Journal (article, 2024-03-20)
Field: Chemistry — Organic Chemistry

Scaffold‐Oriented Asymmetric Catalysis: Conformational Modulation of Transition State Multivalency during a Catalyst‐Controlled Assembly of a Pharmaceutically Relevant Atropisomer A new class of superbasic, bifunctional peptidyl guanidine catalysts is presented, which enables the organocatalytic, atroposelective synthesis of axially chiral quinazolinediones. Computational modeling unveiled the conformational modulation of the catalyst by a novel phenyl urea N-cap, that preorganizes the structure into the active, folded state. A previously unanticipated noncovalent interaction involving a difluoroacetamide acting as a hybrid mono- or bidentate hydrogen bond donor emerged as a decisive control element inducing atroposelectivity. These discoveries spurred from a scaffold-oriented project inspired from a fascinating investigational BTK inhibitor featuring two stable chiral axes and relies on a mechanistic framework that was foreign to the extant lexicon of asymmetric catalysis. Chemistry ; Catalysis ; Guanidine ; Scaffold ; Hydrogen bond ; Bifunctional ; Combinatorial chemistry ; Chirality (physics) ; Stereochemistry ; Nanotechnology ; Materials science ; Organic chemistry ; Molecule ; Computer science Axial and Atropisomeric Chirality Synthesis ; Molecular spectroscopy and chirality ; Chemical Synthesis and Analysis
Authors: Qi‐Long Zhang | Xu Zhou | Xing Zhang | Lingyi Shen | Xu Hong | Zhiyong Wang | Chao Huang | Carl Redshaw | Bi‐Xue Zhu
Source: Microchemical Journal (article, 2024-10-30)
Field: Chemistry — Spectroscopy

Novel AIE [2 + 2] Schiff base macrocycles containing a 2,6-pyridylimide skeleton: Self-assembly and Cu2+ sensing Schiff base ; Skeleton (computer programming) ; Chemistry ; Base (topology) ; Combinatorial chemistry ; Polymer chemistry ; Computer science Molecular Sensors and Ion Detection ; Luminescence and Fluorescent Materials ; Supramolecular Chemistry and Complexes
Authors: Barbara Trzebicka | Wojciech Wałach | Piotr Kurcok | Marek Kowalczuk
Source: Polymers for Advanced Technologies (article, 2024-05-01)
Field: Materials Science — Biomaterials

Ring‐opening (co)polymerization strategies of selected oxacyclic monomers to control and provide tailored polymers with desired properties Abstract Ring‐opening polymerization (ROP) is a versatile synthetic method used to produce polymers from cyclic monomers, particularly oxacyclic monomers such as lactones and cyclic ethers. Oxacyclic monomers polymerize with anionic or cationic initiators. For selected monomers, such as glycidol, β‐butyrolactone and higher lactones, methods, and mechanisms of polymerization are presented, the understanding of which has allowed control of these processes. The use of appropriate polymerization techniques and methods, as well as conducting the copolymerization, mainly block copolymerization, makes it possible to control the architecture, molar mass, and end groups of the resulting polymers. These parameters determine the properties of macromolecules, such as solubility, ability to aggregate in aqueous solutions, thermoresponsiveness, and degradability. By carefully selecting monomers, catalysts, and polymerization conditions, ROP strategies can be tailored to produce polymers with precise molecular structures and desired properties for a wide range of applications. This review mainly focuses on precisely controlled syntheses that lead to well‐defined macromolecules consisting mostly of polyether and/or polyester chains. Materials science ; Monomer ; Polymer ; Polymerization ; Ring (chemistry) ; Polymer science ; Polymer chemistry ; Chemical engineering ; Organic chemistry ; Composite material ; Engineering biodegradable polymer synthesis and properties ; Advanced Polymer Synthesis and Characterization ; Synthesis and properties of polymers
Authors: Joanna Bojarska | Krzysztof Łyczko | Adam Mieczkowski
Source: Crystals (article, 2024-01-28)
Field: Chemistry — Organic Chemistry

Synthesis, Crystal Structure and Supramolecular Features of Novel 2,4-Diaminopyrimidine Salts The crystal structures and the supramolecular architectures of a series of novel salts originating from 2,4-diaminopyrimidine and four different chain dicarboxylic acids are reported. For this purpose, 2,4-diaminopyrimidin-1-ium 2,2′-thio(acetic)acetate (1), 2,4-diaminopyrimidin-1-ium monoglutarate (2), 2,4-diaminopyrimidin-1-ium 3,3′-dithio(propionic)propionate (3) and 2,4-diaminopyrimidin-1-ium suberate (4) were synthesized in good to high yields from 2,4-diaminopyrimidine and appropriate dicarboxylic acids (2,2′-thiodiacetic acid, glutaric acid, 3,3′-dithiodipropionic acid and suberic acid, respectively). Each of the compounds were formed as a monohydrate and compound 4 additionally co-crystallized with the suberic acid molecule. Despite the similar structures of compounds 1 and 2 as well as 3 and 4, subtle but important differences are observed in their crystal packing and H-bonding patterns, especially between 3 and 4. Supramolecular self-assemblies can be distinguished through different interactions considering anions, leading to diverse H-bonding motifs, which also include sulphur atoms in 1 and 3, at the upper level of supramolecular architecture. Notably, the basic motif is always the same—2,4-diaminopyrimidine-based homosynthon R22(8) via N-H∙∙∙N interactions. The impact of diverse types of intermolecular interactions was evaluated by Hirshfeld analysis, while the propensity of atom pairs of elements to build interactions was calculated using enrichment ratios. Although compounds 1 and 3 contain S-atoms, the percentage of S-derived interactions is rather low. In 1, the contribution of S∙∙∙H/H∙∙∙S, S∙∙∙C/C∙∙∙S, S∙∙∙N/N∙∙∙S intermolecular contacts is 5.7%. In 2, the contribution of S∙∙∙H/H∙∙∙S accounts for only 0.6%. Supramolecular chemistry ; Crystal structure ; Chemistry ; Crystallography ; Materials science ; Combinatorial chemistry ; Stereochemistry Synthesis and Characterization of Heterocyclic Compounds ; Synthesis and biological activity ; Crystal structures of chemical compounds
Authors: Tongkun Wang | Song Luo | M. Shah | Long Qi | Geoffrey A. Tompsett | Michaël T. Timko | Scott M. Auerbach | Wei Fan
Source: Chemistry of Materials (article, 2024-01-08)
Field: Chemistry — Inorganic Chemistry

Removing Fluoride from Double Four-Membered Rings Yielding Defect-Free Zeolites under Mild Conditions Using Ozone We have investigated ozone treatment of as-made LTA zeolites under mild temperature conditions (175 °C) using experiments and periodic DFT as a method of energy savings and engineering defects such as silanol nests in comparison with conventional calcination at 550 °C. We have studied ozone treatment on LTA samples synthesized with 1,2-dimethyl-3-(4-methylbenzyl) imidazolium (denoted as “BULKY”) as the primary organic structure-directing agent (OSDA) and with various amounts of tetramethylammonium (TMA) as a secondary OSDA. Ozone treatment of LTA-BULKY at 175 °C was found to give defect-free, pristine LTA materials as determined by 29Si NMR, 13C NMR, Raman spectra, and DFT to assign the spectra. This represents a significant and unexpected finding: that fluoride ions can be completely removed from double four-membered rings (D4Rs) under such mild conditions. Ozone treatment of LTA-BULKY-TMA samples removed BULKY but left behind TMA/F, giving a new and more diverse structural landscape of Si environments in LTA. Ab initio MetaDynamics calculations provide pathways with relatively low barriers, explaining how fluoride ions can be removed from D4Rs, leaving behind defect-free LTA materials under mild conditions. Silanol ; Calcination ; Fluoride ; Ozone ; Raman spectroscopy ; Superacid ; Ion ; Metadynamics ; Materials science ; Tetramethylammonium ; Chemistry ; Inorganic chemistry ; Computational chemistry ; Organic chemistry ; Catalysis ; Molecular dynamics Zeolite Catalysis and Synthesis ; Inorganic Fluorides and Related Compounds ; Mesoporous Materials and Catalysis