jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Mengmeng Zhang | Yue Xu | Xudong Peng | Hongyu Chen | Hong Wang
Source: Chemical Communications (article, 2022-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Controllable synthesis of gold nanoparticle dimers <i>via</i> site-selective growth Random aggregation of nanoparticles follows step-growth kinetics, and thus the synthesis of large nanoparticle dimers is still a challenge. Here, we report a site-selective growth route to producing gold nanoparticle dimers in a high yield of up to 71%. The polymer contraction exposed two tips of gold nanorods, which provided active sites for further growth, setting the ability for a high yield of large dimers. Methods to fine tune the reaction rate allowed us to control the spacing between nanoparticles, giving a good SERS performance. Our method was shown to make up for the shortcomings of the existing synthetic method, and to achieve the synthesis of large dimers in solution. Colloidal gold ; Nanoparticle ; Nanorod ; Yield (engineering) ; Nanotechnology ; Materials science ; Combinatorial chemistry ; Chemistry Gold and Silver Nanoparticles Synthesis and Applications ; Nanocluster Synthesis and Applications
Authors: Bao Xuan Tran | Seungmo Yang | Hyun‐Joong Kim | Jae‐Hyun Ha | Seongsoo Yoon | Changsoo Kim | Kyoung‐Woong Moon | Won‐Chang Choi | Chanyong Hwang | Jung‐Il Hong
Source: Advanced Electronic Materials (article, 2022-10-17)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Electrical Manipulation of Oxygen Ion Migrations for the Voltage‐Controlled Adjustment of Magnetic Anisotropy and Optimized Skyrmion Generations Abstract With the prospect of energy‐efficient spintronics by voltage‐controlled magnetic anisotropy (VCMA), various mechanisms are investigated involving electron orbital state modulations for enhanced spin–orbit interactions, couplings with piezoelectric strain, and electrochemical effect at the interface within diverse magnetoelectric coupled material systems. In the present work, chemistry and spatial distributions of atoms are fine‐tuned at the interface between ferromagnetic Co and partially oxidized Gd layers via voltage‐controlled ion migrations, achieving highly sensitive and stable VCMA operations. With combined actions of chemical diffusion and electrical driving of oxygen through amorphous Gd layer, asymmetric electrical adjustments of magnetic anisotropy could be established. Accompanied changes in the domain morphologies in the magnetic thin film layers could also be confirmed at room temperature. As the fine‐adjustments of domain morphology are essential for the skyrmions generation, voltage‐controlled interfacial chemistry and magnetic anisotropy provide an effective route to stable skyrmion generations and manipulations in the low‐power spintronics technology. Spintronics ; Materials science ; Magnetic anisotropy ; Condensed matter physics ; Ferromagnetism ; Anisotropy ; Skyrmion ; Ion ; Amorphous solid ; Voltage ; Nanotechnology ; Magnetic field ; Magnetization ; Chemistry ; Physics ; Crystallography Multiferroics and related materials ; Magnetic properties of thin films ; ZnO doping and properties
Authors: Timo Rheinberger | Marc J. K. Ankoné | Dirk W. Grijpma | Frederik R. Wurm
Source: European Polymer Journal (article, 2022-09-27)
Field: Materials Science — Biomaterials

Real-Time 1H and 31P NMR spectroscopy of the copolymerization of cyclic phosphoesters and trimethylene carbonate reveals transesterification from gradient to random copolymers Copolymerization is the general approach to combine properties of different polymers in a single material. We prepared the first trimethylene carbonate (TMC) phosphoester (PE) copolymers by statistical copolymerization using either stannous octanoate or 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as the respective catalyst. Variation of comonomer feed, reaction temperature and solvent, resulted in a library of copolymers with molar masses of up to 83,000 g/mol and moderate molar mass dispersities (<1.8). The monomer consumptions during the copolymerizations were followed by real-time 1H and 31P NMR spectroscopy in solution and in the bulk. As ring-opening copolymerization of cyclic esters often leads to gradient copolymers, also TMC and PE copolymerizations resulted in gradient copolymers, i.e. P(TMC-grad-PE)s, with different gradient strength depending on the copolymerization conditions. If a suitable transesterification catalyst like stannous octanoate was used, randomization of the gradient copolymer occurred. The 31P NMR shift of incorporated phosphoester units was used as a probe to monitor the randomization of the gradient copolymers in real-time by 31P NMR spectroscopy. The P-comonomer acts as an ideal NMR probe for in situ monitoring the changes of the copolymers’ microstructure during the transesterification by following the evolution of diads and triads. This paper focusses on the randomization procedure and gives detailed information about the copolymer structure and the kinetics of the copolymerization. The data give the possibility to understand randomization processes on a molecular scale and to fine-tune properties of polycarbonate-polyphosphoester copolymers in future applications. Copolymer ; Comonomer ; Polymer chemistry ; Transesterification ; Polycarbonate ; Monomer ; Trimethylene carbonate ; Materials science ; Nuclear magnetic resonance spectroscopy ; Chemistry ; Polymer ; Organic chemistry ; Catalysis biodegradable polymer synthesis and properties ; Carbon dioxide utilization in catalysis ; Synthetic Organic Chemistry Methods
Authors: Svetlana Lukáš Petrova | Vladimir Sincari | Rafał Konefał | Ewa Pavlová | Martin Hrubý | Václav Pokorný | Eliézer Jäger
Source: ACS Omega (article, 2022-11-17)
Field: Chemistry — Organic Chemistry

Microwave Irradiation-Assisted Reversible Addition–Fragmentation Chain Transfer Polymerization-Induced Self-Assembly of pH-Responsive Diblock Copolymer Nanoparticles [Image: see text] Herein, we present a versatile platform for the synthesis of pH-responsive poly([N-(2-hydroxypropyl)]methacrylamide)-b-poly[2-(diisopropylamino)ethyl methacrylate] diblock copolymer (PHPMA-b-PDPA) nanoparticles (NPs) obtained via microwave-assisted reversible addition–fragmentation chain transfer polymerization-induced self-assembly (MWI-PISA). The N-(2-hydroxypropyl) methacrylamide (HPMA) monomer was first polymerized to obtain a macrochain transfer agent with polymerization degrees (DPs) of 23 and 51. Subsequently, using mCTA and 2-(diisopropylamino)ethyl methacrylate (DPA) as monomers, we successfully conducted MWI-PISA emulsion polymerization in aqueous solution with a solid content of 10 wt %. The NPs were obtained with high monomer conversion and polymerization rates. The resulting diblock copolymer NPs were analyzed by dynamic light scattering (DLS) and cryogenic-transmission electron microscopy (cryo-TEM). cryo-TEM studies reveal the presence of only NPs with spherical morphology such as micelles and polymer vesicles known as polymersomes. Under the selected conditions, we were able to fine-tune the morphology from micelles to polymersomes, which may attract considerable attention in the drug-delivery field. The capability for drug encapsulation using the obtained in situ pH-responsive NPs, the polymersomes based on PHPMA(23)-b-PDPA(100), and the micelles based on PHPMA(51)-b-PDPA(100) was demonstrated using the hydrophobic agent and fluorescent dye as Nile red (NR). In addition, the NP disassembly in slightly acidic environments enables fast NR release. Chain transfer ; Methacrylamide ; Polymerization ; Copolymer ; Micelle ; Polymersome ; Polymer chemistry ; Dynamic light scattering ; Materials science ; Raft ; Reversible addition−fragmentation chain-transfer polymerization ; Methacrylate ; Monomer ; Nile red ; Nanoparticle ; Radical polymerization ; Polymer ; Chemical engineering ; Chemistry ; Amphiphile ; Aqueous solution ; Organic chemistry ; Nanotechnology ; Fluorescence ; Acrylamide Advanced Polymer Synthesis and Characterization ; Surfactants and Colloidal Systems
Authors: Yue Xiao | Lu Han | Jihai Tang | Lifang Tian | Zhuxiu Zhang | Lixiong Zhang | Dong Yang | Xu Qiao
Source: Chemical Communications (article, 2022-01-01)
Field: Chemistry — Inorganic Chemistry

Fabricating defect-rich metal–organic frameworks <i>via</i> mixed linker-induced crystal transformation Defect-rich hcp UiO-66-NO<sub>2</sub> was synthesized <i>via</i> mixed linker-induced crystal transformation from fcu UiO-66-NO<sub>2</sub>/NH<sub>2</sub>. The defect concentration and porosity of hcp UiO-66-NO<sub>2</sub> can be fine-tuned by varying the BDC-NH<sub>2</sub>/BDC-NO<sub>2</sub> ratio, which in turn endowed hcp UiO-66-NO<sub>2</sub> with superior catalytic performance in the ring-opening reaction of epoxides with alcohols. Linker ; Catalysis ; Porosity ; Crystal (programming language) ; Materials science ; Ring (chemistry) ; Metal-organic framework ; Reaction conditions ; Transformation (genetics) ; Crystallography ; Metal ; Chemical engineering ; Chemistry ; Organic chemistry ; Composite material ; Metallurgy Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications ; Chemical Synthesis and Reactions
Authors: Alexandre Poirot | Corinne Vanucci‐Bacqué | Béatrice Delavaux‐Nicot | Nathalie Saffon‐Merceron | Charles-Louis Serpentini | Nadine Leygue | Florence Bedos‐Belval | Éric Benoist | Suzanne Fery‐Forgues
Source: Photochemical & Photobiological Sciences (article, 2022-09-30)
Field: Materials Science — Materials Chemistry

Luminescent fac-[ReX(CO)3(phenyl-pyta)] (X = Cl, Br, I) complexes: influence of the halide ligand on the electronic properties in solution and in the solid state Ligand (biochemistry) ; Luminescence ; Iodide ; Halide ; Bromide ; Chemistry ; Halogen ; Denticity ; Rhenium ; Crystallography ; Photochemistry ; Electrochemistry ; Chloride ; Inorganic chemistry ; Crystal structure ; Physical chemistry ; Materials science ; Alkyl ; Organic chemistry Luminescence and Fluorescent Materials ; Nanocluster Synthesis and Applications ; Nanoplatforms for cancer theranostics
Authors: Jidi Li | Yuanchao Liu | Sihao Qian | Zhi Geng | Qichao Pan | Lisha Ye | Lianwang Zhang | Jianwen Bao | Yong He | Bo Zhu
Source: Surfaces and Interfaces (article, 2022-09-02)
Field: Materials Science — Materials Chemistry

Reactive graphene by one-pot grafting toward tough and fire-retardant thermoset nanocomposites Functionalized graphene with reactive moieties is promising to significantly enhance the interfacial strength of graphene materials with thermoset resins and their dispersion in resins. Most of the previous reactive graphene materials were prepared through the covalent modification of oxidation-produced oxygen-containing groups of the graphene oxides, which, however, have intensive defects and weakened mechanical strength, Young's modulus, and thermal stability. Starting from the commercially available graphene, we herewith developed a one-pot direct grafting approach for the fabrication of epoxy-reactive graphene. This grafting is achieved by the diazonium addition reaction of 10-(2′,5′-dihydroxyphenyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (ODOPB) functionalized 4-aminobenzoic acid with the pristine graphene sheets. We further demonstrated this one-pot grafting approach could be controlled well by simply changing the ODOPB functionalized 4-aminobenzoic acid concentration to fine-tune the grafting density. In the graphene reinforced epoxy composite, ODOPB moieties grafted onto graphenes act as anchors, ensuring the improved dispersion of graphene sheets. The ODOPB functionalized graphene composites demonstrated a dramatically enhanced fracture toughness (a critical-stress-intensity factor, KIC value of 2.1) than graphene-epoxy composites (a KIC value of 1.3) and neat epoxy material (a KIC value of 1.8). Furthermore, its flame retardance, as evaluated by limit oxygen index (LOI) tests, improved by 29.5%. This one-pot approach provides an easily up-scalable and efficient approach for enhancing the interfacial strength and the dispersibility of graphene composites and incorporating new functions into polymer nanocomposites by graphene carriers. Graphene ; Materials science ; Epoxy ; Thermosetting polymer ; Composite material ; Nanocomposite ; Oxide ; Grafting ; Polymer ; Nanotechnology Graphene research and applications ; Flame retardant materials and properties ; Graphene and Nanomaterials Applications
Authors: Kon Son | Shinji Takeoka | Yoshihiro Ito | Motoki Ueda
Source: Biomacromolecules (article, 2022-06-14)
Field: Materials Science — Biomaterials

End-Sealing of Peptide Nanotubes by Cationic Amphiphilic Polypeptides and Their Salt-Responsive Accordion-like Opening and Closing Behavior One strategy to prepare phase-separated co-assembly is to use the existing assembly as a platform to architect structures. For this purpose, the edge of a sheet or tube-shaped molecular assembly, which is less hydrophilic than the bulk region can become a starting point to build assembly units to realize more complex structures. In this study, we succeeded in preparing rod-shaped nanocapsules with previously unachieved sealing efficiency (>99%) by fine-tuning the properties of cationic amphiphilic polypeptides to seal the ends of neutral charge nanotubes. In addition, we demonstrated the nanocapsule's reversible responsiveness to salt. In high salt concentrations, a decrease in electrostatic repulsion between cationic polypeptides caused tearing and shrinking of the nanocapsule's sealing dome, which resulted in an opened nanotube. On the other hand, when salt was removed, the electrostatic repulsion among the cationic peptides localizing on the edge of opened nanocapsules was recovered, and the sealing membrane swelled up like an accordion to create a distance between the peptides, resulting in the restoration of the seal. Nanocapsules ; Cationic polymerization ; Amphiphile ; Nanotube ; Chemistry ; Nanotechnology ; Membrane ; Chemical engineering ; Materials science ; Polymer chemistry ; Carbon nanotube ; Nanoparticle ; Organic chemistry ; Polymer ; Copolymer Supramolecular Self-Assembly in Materials ; Chemical Synthesis and Analysis ; Polydiacetylene-based materials and applications
Authors: Walace D. do Pim | S. Marcotte | Alexandros A. Kitos | Paul Richardson | Peter J. Pallister | Muralee Murugesu
Source: Inorganic Chemistry (article, 2022-07-19)
Field: Chemistry — Inorganic Chemistry

Straightforward Mechanosynthesis of a Phase-Pure Interpenetrated MOF-5 Bearing a Size-Matching Tetrazine-Based Linker The archetypal metal-organic framework-5 (MOF-5 or IRMOF-1) has been explored as a benchmark sorbent material with untapped potential to be studied in the capture and storage of gases and chemical confinement. Several derivatives of this framework have been prepared using the multivariate (MTV) strategy through mixing size-matching linkers to isolate, for example, MIXMOFs that outperform same-linker congeners when employed as gas reservoirs. Herein, we describe a straightforward protocol that uses mechanosynthesis (solvent-free grinding) followed by mild activation in dimethylformamide (DMF)/CHCl<sub>3</sub> (40 °C and ambient pressure) to synthesize a functional phase-pure interpenetrated MOF-5 (<i>int</i>-MOF-5) bearing the size-matching 1,4-benzene dicarboxylate (BDC) and 1,2,4,5-tetrazine-3,6-dicarboxylate (TZDC) linkers in the backbone of the interpenetrated MIXMOF. We found that the grinding involving a mixture of H<sub>2</sub>TZDC and H<sub>2</sub>BDC in a 1:4 ratio (20% of H<sub>2</sub>TZDC) in the presence of zinc(II) acetate yields a crystalline solid that upon activation forms a phase-pure <i>int</i>-MOF-5 herein referred to as 20%TZDC-MOF-5. The crystalline phase, thermal stability, and porous structure of 20%TZDC-MOF-5 were thoroughly characterized, and the gas adsorption performance of the MIXMOF was investigated through the isotherms of N<sub>2</sub> and H<sub>2</sub> at 77 K and CO<sub>2</sub> at 273 and 296 K. The pore size distribution for 20%TZDC-MOF-5 was found to be very similar to that determined using single crystals of the same-linker <i>int</i>-MOF-5. The presence of TZDC in the MIXMOF led to a slight increase in the uptake values for both H<sub>2</sub> and CO<sub>2</sub>, suggesting that beneficial interactions take place. To the best of our knowledge, this is the first report presenting a suitable protocol to yield a functionalized <i>int</i>-MOF-5 as a promising means of synergistically fine-tuning the confinement of small target molecules such as CO<sub>2</sub> and H<sub>2</sub>. Chemistry ; Tetrazine ; Mechanosynthesis ; Metal-organic framework ; Linker ; Phase (matter) ; Propane ; Adsorption ; Chemical engineering ; Thermal stability ; Sorbent ; Porosity ; Physical chemistry ; Organic chemistry Metal-Organic Frameworks: Synthesis and Applications ; Crystallography and molecular interactions ; Boron and Carbon Nanomaterials Research
Authors: Erkan Ertürk | Tolga A. Yeşil
Source: The Journal of Organic Chemistry (article, 2022-09-22)
Field: Chemistry — Organic Chemistry

Catalyst-Tuned Electrophilic Chlorination of Diverse Aromatic Compounds with Sulfuryl Chloride and Regioselective Chlorination of Phenols with Organocatalysts In this work, we demonstrate that diverse aromatic compounds can be selectively chlorinated through the fine-tuning of the reactivity of sulfuryl chloride (SO<sub>2</sub>Cl<sub>2</sub>) by organocatalysts. Acetonitrile has been identified to activate SO<sub>2</sub>Cl<sub>2</sub> most strongly, thus enabling even chlorination of <i>p</i>-xylene with high yields. 1,4-Dioxane effects chlorination of oxidation-labile aromatic compounds such as <i>p</i>-cresol and 2-naphthol with high yields, 95% and 85%, respectively. An array of potential catalysts has been screened for <i>ortho</i>- and <i>para</i>-selective chlorination of phenols. Thus, we found that acetonitrile, (<i>S</i>)-BINAPO (5 mol %), and diisopropyl ether (4.00 equiv) can catalyze the chlorination of phenols in a <i>para</i>-selective manner (with ≤4:96 <i>o</i>:<i>p</i> ratio), whereas Nagasawa's bis-thiourea (1 mol %), phenyl boronic acid (5 mol %), and (<i>S</i>)-diphenylprolinol (1 mol %) exhibit high <i>ortho</i> selectivity [with ≤99:1 <i>o</i>:<i>p</i> ratio by (<i>S</i>)-diphenylprolinol]. Sulfuryl chloride ; Chemistry ; Acetonitrile ; Organic chemistry ; Halogenation ; Phenols ; Catalysis ; Friedel–Crafts reaction ; Regioselectivity ; Chloride ; Electrophile ; Medicinal chemistry Chemical Synthesis and Reactions ; Vanadium and Halogenation Chemistry ; Oxidative Organic Chemistry Reactions
Authors: Hajime Torii | Akari Kimura | Takanori Sakai
Source: Physical Chemistry Chemical Physics (article, 2022-01-01)
Field: Chemistry — Physical and Theoretical Chemistry

Nature of hydrogen-bond-enhanced halogen bonding viewed through electron density changes Elucidating the mechanism of how we can achieve fine tuning of intermolecular interaction strength will be helpful for designing functionally important molecules. In the present study, a theoretical analysis is conducted, by examining the electron density changes, for two halogen-bonding iodinated systems whose halogen-bond strengths have been considered to be enhanced by the presence of a hydrogen-bond donating group (termed hydrogen-bond-enhanced halogen bonding). It is shown that, contrary to the expectation obtained from the enhancement of electrostatic potential along the line extended from the C-I bond, the anisotropy of electron distribution on the iodine atom remains nearly the same. This means that the hydrogen bond and halogen bond contribute almost independently and additively to the enhancement of electrostatic potential, indicating the nature of this enhancement and, in a more general sense, the relationship between the strength and the extent of directionality of halogen bonding. Halogen bond ; Hydrogen bond ; Intermolecular force ; Halogen ; Chemistry ; Sextuple bond ; Bond strength ; Bond order ; Chemical physics ; Electron density ; Three-center two-electron bond ; Chemical bond ; Atom (system on chip) ; Molecule ; Bent bond ; Electron ; Computational chemistry ; Bond length ; Organic chemistry ; Physics ; Quantum mechanics Crystallography and molecular interactions ; Bioactive Compounds and Antitumor Agents ; Crystallization and Solubility Studies
Authors: Albert Guirguis | Ludovic F. Dumée | Daniel J. Eyckens | Melissa K. Stanfield | Yanting Yin | Gunther G. Andersson | Lingxue Kong | Luke C. Henderson
Source: Advanced Materials Interfaces (article, 2022-01-31)
Field: Materials Science — Materials Chemistry

Size‐Controlled Nanosculpture of Cylindrical Pores across Multilayer Graphene via Photocatalytic Perforation Abstract One of the bottlenecks in realizing the potential of nanoporous graphene assemblies is the difficulty of engineering narrow pores and high surface density distributions, with a nanometer resolution across multilayer graphene assemblies using scalable approaches. Here, the authors develop a photocatalyzed perforation protocol to incorporate nanopores across modified graphene assemblies via localizing the oxidation during the photo‐excitation process between photo‐initiators and graphitic assemblies under the ultraviolet–visible stimuli. Nanopores are engineered across the graphene nanostructures with a pore size range varying from 20 to 100 nm depending on the irradiation duration, as well as tunable densities of 10 1 –10 3 pores/ µ m 2 on the same order of the loaded nanocatalysts to the graphene surfaces. By fine‐tuning the graphene chemistry and the physical dimension of photo‐initiators, as well as their concentrations across graphitic planes used during the perforation, the diameter, and the density distributions of generated nanopores across graphene, can be rationally confined, avoiding merging between pores during the nanopore formation. These porosity parameters engineered across graphene nanosieves are in the same order obtained by other nanolithographic techniques. Plus, this sustainable route may boost the potential of porous graphene assemblies in energy‐efficient nanotechnologies based on separation and catalytic processes. Graphene ; Materials science ; Nanopore ; Nanoporous ; Nanotechnology ; Perforation ; Porosity ; Photocatalysis ; Catalysis ; Composite material Graphene research and applications ; Nanopore and Nanochannel Transport Studies ; Covalent Organic Framework Applications