jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Duarte Borralho | Sara Realista | Telmo Nunes | M. E. Melo Jorge | Paulo N. Martinho
Source: ChemRxiv (preprint, 2024-04-16)
Field: Materials Science — Materials Chemistry

Immobilisation of Ni(II) and Zr(IV) metal-organic frameworks on electrodes using electrophoretic deposition Metal-organic frameworks are materials which are constituted by an inorganic centre and organic ligand offering high crystallinity, high surface area and high permanent porosity. These structures show promising results in multiple applications due to their properties, especially their capacity for open-metal sites. The use of these structures for electrochemical applications, such as sensors and electrocatalysts, require their immobilisation on a conductive surface, as they are obtained in powder form using the most common method – solvothermal synthesis. Electrophoretic deposition, an indirect method, which focus on immobilising these materials in powder form postsynthesis on the surface of a conductive structure can be used for their immobilisation, that may offer several advantages in relation with other methods if further developed – those being simplicity and universality. This work focuses on the synthesis, immobilisation, and stability studies of these MOFs in the presence of water and in oxidative aqueous electrochemical medium. The obtained metal-organic framework powders and films were characterised using X-rays diffraction, Fourier Transform infrared spectroscopy and scanning-electron microscopy. The electrochemical studies were made using cyclic voltammetry. It was possible to form films of the MOFs UiO-66, UiO-66-NH2 and Ni-MOF-74 on the surface of fluoride-doped tin oxide glass using electrophoretic deposition, with all three MOF films showing stability in water and the UiO- 66 and UiO-66-NH2 films showing high stability as well in highly basic oxidative aqueous electrochemical medium. Electrophoretic deposition ; Metal-organic framework ; Electrode ; Deposition (geology) ; Electrophoresis ; Materials science ; Metal ; Zirconium ; Inorganic chemistry ; Chemistry ; Chemical engineering ; Nanotechnology ; Metallurgy ; Chromatography ; Organic chemistry ; Physical chemistry ; Geology ; Adsorption ; Engineering ; Coating Mesoporous Materials and Catalysis
Authors: Khushdeep Kaur | Yovan de Coene | Koen Clays | Paramjit Kaur | Kamaljit Singh
Source: Journal of Molecular Structure (article, 2024-04-06)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Nonlinear optical response of 1H-indene-based donor-acceptor chromophores. Influence of the higher-lying states on the first hyperpolarizability Hyperpolarizability ; Chemistry ; Chromophore ; Excited state ; Indene ; Acceptor ; Intramolecular force ; Photochemistry ; Oscillator strength ; Computational chemistry ; Atomic physics ; Molecule ; Stereochemistry ; Quantum mechanics ; Organic chemistry ; Physics Nonlinear Optical Materials Research ; Synthesis and Properties of Aromatic Compounds ; Nonlinear Optical Materials Studies
Authors: Jacob D. Teeter | Mamun Sarker | Wenchang Lu | Chenggang Tao | Arthur P. Baddorf | Jingsong Huang | Kunlun Hong | J. Bernholc | Alexander Sinitskii | An‐Ping Li
Source: Communications Chemistry (article, 2024-08-31)
Field: Materials Science — Materials Chemistry

Deposition temperature-mediated growth of helically shaped polymers and chevron-type graphene nanoribbons from a fluorinated precursor Graphene nanoribbons (GNRs) of precise size and shape, critical for controlling electronic properties and future device applications, can be realized via precision synthesis on surfaces using rationally designed molecular precursors. Fluorine-bearing precursors have the potential to form GNRs on nonmetallic substrates suitable for device fabrication. Here, we investigate the deposition temperature-mediated growth of a new fluorine-bearing precursor, 6,11-diiodo-1,4-bis(2-fluorophenyl)-2,3-diphenyltriphenylene (C<sub>42</sub>H<sub>24</sub>F<sub>2</sub>I<sub>2</sub>), into helically shaped polymer intermediates and chevron-type GNRs on Au(111) by combining scanning tunneling microscopy, X-ray photoelectron spectroscopy, and density functional theory simulations. The fluorinated precursors do not adsorb on the Au(111) surface at lower temperatures, necessitating an optimum substrate temperature to achieve maximum polymer and GNR lengths. We compare the adsorption behavior with that of pristine chevron precursors and discuss the effects of C-H and C-F bonds. The results elucidate the growth mechanism of GNRs with fluorine-bearing precursors and establish a foundation for future synthesis of GNRs on nonmetallic substrates. Graphene nanoribbons ; Graphene ; Fabrication ; Fluorine ; Materials science ; Deposition (geology) ; Nanotechnology ; Polymer ; Chevron (anatomy) ; Chemical engineering ; Composite material ; Metallurgy Graphene research and applications ; Molecular Junctions and Nanostructures ; 2D Materials and Applications
Authors: Charlotte Bocquelet | Nathan Rougier | Huu-Nghia Le | Laurent Veyre | Chloé Thieuleux | Roberto Melzi | Armin Purea | Daniel Banks | James Kempf | Quentin Stern | Ewoud Vaneeckhaute | Sami Jannin
Source: ChemRxiv (preprint, 2024-03-29)
Field: Chemistry — Spectroscopy

Boosting 1H and 13C NMR signals by orders of magnitude on a bench Sensitivity is often the Achilles’ heel of liquid-state nuclear magnetic resonance (NMR) experiments. This problem is perhaps most pressing at the lowest fields (e.g., 80 MHz 1H frequency), with rapidly increasing access to NMR through benchtop systems, but also sometimes for higher-field NMR systems from 300 MHz to 1.2 GHz. Hyperpolarization by dissolution Dynamic Nuclear Polarization (dDNP) can address this sensitivity limitation. However, dDNP implies the use of massive and complex cryogenic and high-field instrumentation which cannot be installed on the bench. We introduce here the very first compact helium-free 1 Tesla tabletop polarizer as a simple and low-cost alternative. After freezing and polarizing the frozen analyte solutions at 77 Kelvin, we demonstrate 1H signal enhancement factors of 100, with rapid 1 second build-up times. The high polarization is subsequently transferred by 1H→13C cross-polarization (CP) to 13C spins. Hyperpolarization in such a simple benchtop polarizer, in combination with the use of hyperpolarizing solid matrices (HYPSOs) may open the way to replenishable hyperpolarization throughout multiple liquid-state NMR experiments. Hyperpolarization (physics) ; Polarizer ; Polarization (electrochemistry) ; Spin isomers of hydrogen ; Induced polarization ; Nuclear magnetic resonance ; Spins ; Nuclear magnetic resonance spectroscopy ; Materials science ; Chemistry ; Physics ; Optics ; Condensed matter physics ; Birefringence Advanced NMR Techniques and Applications ; Atomic and Subatomic Physics Research ; Solid-state spectroscopy and crystallography
Authors: Sana Shaikh | Manish Hate | Ramesh Chaughule
Source: Oriental Journal Of Chemistry (article, 2024-12-25)
Field: Materials Science — Materials Chemistry

Eco-friendly and Sustainable Biosynthesis of ZnO Nanomaterials for Photocatalytic Degradation of Industrial Effluent under Natural sunlight This study investigates the synthesis, characterization, and use of Zinc oxide nanoparticles (ZnONPs) for degrading water sample from a common effluent treatment plant (WSCETP) and a specific industrial source (Water Sample from Padmaja Laboratories, abbreviated as WSPL). Zinc oxide nanoparticles were produced through a green microwave-assisted approach with Moringa Oleifera Lam and analysed using various spectroscopic and microscopic techniques. UV-Visible spectroscopy identified a peak at 308 nm and a band gap of 3.06 eV. Fourier Transform Infrared Spectroscopy confirmed Zn-O stretching and various organic groups. X-ray diffraction analysis indicated a hexagonal wurtzite structure with a crystal size of 21 nm, while Field Emission Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy revealed a uniform, spherical morphology, and high purity. Photocatalytic tests showed optimal Chemical Oxygen Demand reductions at 7.5 g/L for Water Sample from Common Effluent Treatment Plant and 10 g/L for Water Sample from Padmaja Laboratories, with pH values of 8.2 and 8.0, respectively. Recyclability tests demonstrated significant activity retention, with Chemical Oxygen Demand reductions of 18% and 62% after four cycles for Water Sample from Common Effluent Treatment Plant and Water Sample from Padmaja Laboratories, respectively. Zinc oxide nanoparticles are effective, recyclable, providing a cost-efficient method for industrial effluent treatment. Wurtzite crystal structure ; Photocatalysis ; Effluent ; Fourier transform infrared spectroscopy ; Zinc ; Chemical oxygen demand ; Chemistry ; Nanoparticle ; Nanomaterials ; Green chemistry ; Nuclear chemistry ; Chemical engineering ; Materials science ; Nanotechnology ; Catalysis ; Wastewater ; Environmental engineering ; Organic chemistry ; Environmental science ; Reaction mechanism Nanoparticles: synthesis and applications
Authors: Nurhayati Nurhayati | Musyarofah Musyarofah | Swastya Rahastama | Dian Mart Shoodiqin | Budi Prayitno | Nurrisma Puspitasari
Source: JURNAL ILMU FISIKA | UNIVERSITAS ANDALAS (article, 2024-02-03)
Field: Materials Science — Materials Chemistry

Study of The Effect of Calcination Temperature on the Phase Composition of ZnO Powder Synthesized via The Sol-Gel Method This study investigated the effect of calcination temperature on the phase composition and crystal size of zinc oxide powders synthesised by the sol-gel method. Zn powder, HCl and NaOH were used as precursors in a multi-step process involving dissolution, titration, gel formation, leaching, drying and calcination at temperatures ranging from 300°C to 700°C for 2 hours. Rietveld analysis of X-ray diffraction (XRD) data using MAUD and Rietica software determined phase composition and crystal size. Initial analysis identified a single simonkolleite phase (Zn5(OH)8Cl2) prior to calcination, which disappeared at 500°C. Wurtzite (ZnO) appeared at 300°C, accompanied by secondary phases (NaCl and ZnCl2). The wurtzite content increased to 81.42 wt% at 700°C. Calcination temperature also influenced crystal size, which ranged from 27.34 nm to 110.61 nm for wurtzite at different temperatures. The results highlight the dynamic changes in phase composition and crystal size with different calcination temperatures, providing valuable insights into tailoring zinc oxide properties for various applications. Calcination ; Composition (language) ; Sol-gel ; Phase (matter) ; Materials science ; Chemical engineering ; Chemistry ; Nanotechnology ; Catalysis ; Organic chemistry ; Art ZnO doping and properties ; Gas Sensing Nanomaterials and Sensors ; Copper-based nanomaterials and applications
Authors: Roman Guntermann | David Helminger | Laura Frey | Peter M. Zehetmaier | Christian Wangnick | Apeksha Singh | Tianhao Xue | Dana D. Medina | Thomas Bein
Source: Angewandte Chemie (article, 2024-08-14)
Field: Materials Science — Materials Chemistry

Tunable Isometric Donor‐Acceptor Wurster‐Type Covalent Organic Framework Photocathodes Abstract Covalent organic frameworks (COFs) offer remarkable versatility, combining ordered structures, high porosity, and tailorable functionalities in nanoscale reaction spaces. Herein, we report the synthesis of a series of isostructural, photoactive Wurster‐type COFs achieved by manipulating the chemical and electronic nature of the Wurster aromatic amine building blocks. A series of donor‐acceptor‐donor (D‐A‐D) Wurster building block molecules was synthesized by incorporating heteroaromatic acceptors with varying strengths between triphenylamine donor groups. These tailored building blocks were integrated into a 2D COF scaffold, resulting in highly crystalline structures and similar morphologies across all COFs. Remarkably, this structural uniformity was also achieved in the synthesis of homogeneous and oriented thin films. Steady‐state photoluminescence revealed a tunable red‐shift in film emission exceeding 100 nm, demonstrating effective manipulation of their optical properties. Furthermore, photoelectrochemical (PEC) water splitting studies exhibited a doubled current density (8.1 μA cm −2 at 0.2 V RHE ) for the COF with the strongest acceptor unit. These findings highlight the potential of Wurster D‐A‐D COFs in photoelectrochemical water splitting devices and pave the way for further exploration of chemical functionality‐reactivity‐property relationships in this promising class of photoactive materials. Triphenylamine ; Isostructural ; Acceptor ; Materials science ; Covalent bond ; Molecule ; Photoluminescence ; Supramolecular chemistry ; Photochemistry ; Chemistry ; Nanotechnology ; Organic chemistry ; Crystal structure ; Optoelectronics Covalent Organic Framework Applications ; Advanced Photocatalysis Techniques ; Metal-Organic Frameworks: Synthesis and Applications
Authors: Fucheng Yin | Lailiang Qu | Yifan Chen | Zhongwen Luo | Lingyi Kong | Xiaobing Wang
Source: Chemistry - A European Journal (article, 2024-03-12)
Field: Chemistry — Organic Chemistry

Stereoselective Synthesis of <i>β, γ‐</i>Fused Bicyclic <i>γ</i>‐Ureasultams via an Intramolecular Mannich and aza‐Michael Addition Cascade A novel approach has been developed for the synthesis of bicyclic β, γ-fused bicyclic γ-ureasultams containing two consecutive chiral centers through an intramolecular Mannich and aza-Michael addition cascade of alkenyl sulfamides. The straightforward practical procedure and readily available starting materials enable the synthesis of variously substituted ureasultams. In addition, bicyclic γ-ureasultams is a class of potential biotin analogues. Bicyclic molecule ; Intramolecular force ; Cascade ; Stereoselectivity ; Michael reaction ; Chemistry ; Stereochemistry ; Combinatorial chemistry ; Organic chemistry ; Catalysis Sulfur-Based Synthesis Techniques ; Organic and Inorganic Chemical Reactions ; Cyclopropane Reaction Mechanisms
Authors: Grzegorz Romanowski | Justyna Budka | Iwona Inkielewicz‐Stępniak
Source: International Journal of Molecular Sciences (article, 2024-05-03)
Field: Chemistry — Inorganic Chemistry

Oxidovanadium(V) Schiff Base Complexes Derived from Chiral 3-amino-1,2-propanediol Enantiomers: Synthesis, Spectroscopic Studies, Catalytic and Biological Activity Oxidovanadium(V) complexes, <b>[(+)VOL<sup>1-5</sup>]</b> and <b>[(-)VOL<sup>1-5</sup>]</b>, with chiral tetradentate Schiff bases, which are products of monocondensation of <i>S</i>(‒)-3-amino-1,2-propanediol or <i>R</i>(+)-3-amino-1,2-propanediol with salicylaldehyde derivatives, have been synthesized. Different spectroscopic methods, viz. <sup>1</sup>H and <sup>51</sup>V NMR, IR, UV-Vis, and circular dichroism, as well as elemental analysis, have been used for their detailed characterization. Furthermore, the epoxidation of styrene, cyclohexene, and two monoterpenes, <i>S</i>(‒)-limonene and (‒)-α-pinene, using two oxidants, aqueous 30% H<sub>2</sub>O<sub>2</sub> or <i>tert</i>-butyl hydroperoxide (TBHP) in decane, has been studied with catalytic amounts of all complexes. Finally, biological cytotoxicity studies have also been performed with these oxidovanadium(V) compounds for comparison with <i>cis</i>-dioxidomolybdenum(VI) Schiff base complexes with the same chiral ligands, as well as to determine the cytoprotection against the oxidative damage caused by 30% H<sub>2</sub>O<sub>2</sub> in the HT-22 hippocampal neuronal cells in the range of their 10-100 μM concentration. Chemistry ; Schiff base ; Enantiomer ; Catalysis ; Salicylaldehyde ; Cyclohexene ; Amino acid ; Circular dichroism ; Chirality (physics) ; Stereochemistry ; Aqueous solution ; Organic chemistry ; Medicinal chemistry ; Biochemistry Vanadium and Halogenation Chemistry ; Polyoxometalates: Synthesis and Applications ; Metal-Catalyzed Oxygenation Mechanisms
Authors: Manijeh Nematpour
Source: ChemistrySelect (article, 2024-10-01)
Field: Chemistry — Organic Chemistry

A Novel Synthesis of Substituted Benzo[1,2,4]Oxadiazine Derivatives <i>Via</i> Copper‐Catalyzed Intermolecular <i>O</i> ‐Arylation of <i>2‐Iodoaniline</i> and <i>N</i> ‐Hydroxyimidoyl Chloride Abstract In this work, a rapid and direct route for the synthesis of benzo[1,2,4]oxadiazine derivatives through a copper iodide‐catalyzed intermolecular O ‐arylation of 2‐iodoaniline and N ‐hydroxyimidoyl chloride has been investigated. The reaction is fast and simple at room temperature and takes place in a reasonable amount of time. No complex ligands or special equipment are required. The use of cheap and available raw materials and catalysts, without column chromatography, performing the reaction in 4 hours, and good efficiency (72–86 %) are notable features of this protocol. The synthesized product is often found in drugs and other bioactive molecules. Chemistry ; Intermolecular force ; Copper ; Copper chloride ; Chloride ; Catalysis ; Medicinal chemistry ; Organic chemistry ; Molecule Synthesis and Biological Evaluation ; Catalytic C–H Functionalization Methods ; Phenothiazines and Benzothiazines Synthesis and Activities
Authors: Marko Gobin | Ivana Nikšić‐Franjić | Nikola Topolovčan
Source: Organic Chemistry Frontiers (article, 2024-11-27)
Field: Chemistry — Inorganic Chemistry

Catalytic haloallylation/Zr-mediated dienyne cyclization/isomerization sequence for tailored cyclopentadiene substitution A synthetic sequence leading to the controlled decoration of cyclopentadienes is reported. This approach allows site-selective installation of different functionalities around the Cp ring, exploiting stereoelectronic features of internal alkynes. Isomerization ; Chemistry ; Substitution (logic) ; Cyclopentadiene ; Sequence (biology) ; Catalysis ; Medicinal chemistry ; Stereochemistry ; Photochemistry ; Organic chemistry ; Biochemistry ; Computer science Asymmetric Hydrogenation and Catalysis ; Catalytic Cross-Coupling Reactions ; Synthetic Organic Chemistry Methods
Authors: Lena Scholtz | J. Gerrit Eckert | Rebecca T. Graf | Alexandra Kunst | K. David Wegner | Nadja C. Bigall | Ute Resch‐Genger
Source: Scientific Reports (article, 2024-05-24)
Field: Materials Science — Materials Chemistry

Correlating semiconductor nanoparticle architecture and applicability for the controlled encoding of luminescent polymer microparticles Luminophore stained micro- and nanobeads made from organic polymers like polystyrene (PS) are broadly used in the life and material sciences as luminescent reporters, for bead-based assays, sensor arrays, printable barcodes, security inks, and the calibration of fluorescence microscopes and flow cytometers. Initially mostly prepared with organic dyes, meanwhile luminescent core/shell nanoparticles (NPs) like spherical semiconductor quantum dots (QDs) are increasingly employed for bead encoding. This is related to their narrower emission spectra, tuneability of emission color, broad wavelength excitability, and better photostability. However, correlations between particle architecture, morphology, and photoluminescence (PL) of the luminescent nanocrystals used for encoding and the optical properties of the NP-stained beads have been rarely explored. This encouraged us to perform a screening study on the incorporation of different types of luminescent core/shell semiconductor nanocrystals into polymer microparticles (PMPs) by a radical-induced polymerization reaction. Nanocrystals explored include CdSe/CdS QDs of varying CdS shell thickness, a CdSe/ZnS core/shell QD, CdSe/CdS quantum rods (QRs), and CdSe/CdS nanoplatelets (NPLs). Thereby, we focused on the applicability of these NPs for the polymerization synthesis approach used and quantified the preservation of the initial NP luminescence. The spectroscopic characterization of the resulting PMPs revealed the successful staining of the PMPs with luminescent CdSe/CdS QDs and CdSe/CdS NPLs. In contrast, usage of CdSe/CdS QRs and CdSe QDs with a ZnS shell did not yield luminescent PMPs. The results of this study provide new insights into structure-property relationships between NP stained PMPs and the initial luminescent NPs applied for staining and underline the importance of such studies for the performance optimization of NP-stained beads. Luminescence ; Materials science ; Quantum dot ; Photoluminescence ; Nanotechnology ; Polymer ; Nanoparticle ; Nanocrystal ; Polyvinylpyrrolidone ; Luminophore ; Polymerization ; Photobleaching ; Fluorescence ; Quantum yield ; Chemical engineering ; Optoelectronics ; Polymer chemistry ; Optics ; Composite material Quantum Dots Synthesis And Properties ; Chalcogenide Semiconductor Thin Films ; Perovskite Materials and Applications
Authors: Yuqing Yao | Chengyuan Shao | Shuwei Wang | Qiufang Gong | Jia Liu | Hua Jiang | Ying Wang
Source: Communications Chemistry (article, 2024-02-27)
Field: Chemistry — Organic Chemistry

Dual-controlled guest release from coordination cages Despite having significant applications in the construction of controlled delivery systems with high anti-interference capability, to our knowledge dual-controlled molecular release has not yet been achieved based on small molecular/supramolecular entities. Herein, we report a dual-controlled release system based on coordination cages, for which releasing the guest from the cage demands synchronously altering the coordinative metal cations and the solvent. The cages, Hg<sub>5</sub>L<sub>2</sub> and Ag<sub>5</sub>L<sub>2</sub>, are constructed via coordination-driven self-assembly of a corannulene-based ligand. While Hg<sub>5</sub>L<sub>2</sub> shows a solvent-independent guest encapsulation in all the studied solvents, Ag<sub>5</sub>L<sub>2</sub> is able to encapsulate the guests in only some of the solvents, such as acetone-d<sub>6</sub>, but will liberate the encapsulated guests in 1,1,2,2-tetrachloroethane-d<sub>2</sub>. Hg<sub>5</sub>L<sub>2</sub> and Ag<sub>5</sub>L<sub>2</sub> are interconvertible. Thus, the release of guests from Hg<sub>5</sub>L<sub>2</sub> in acetone-d<sub>6</sub> can be achieved, but requires two separate operations, including metal substitutions and a change of the solvent. Dual-controlled systems as such could be useful in complicated molecular release process to avoid those undesired stimulus-responses. Supramolecular chemistry ; Acetone ; Solvent ; Chemistry ; Dual role ; Coordination complex ; Ligand (biochemistry) ; Metal ; Nanotechnology ; Combinatorial chemistry ; Polymer chemistry ; Molecule ; Materials science ; Organic chemistry ; Receptor Supramolecular Chemistry and Complexes ; Porphyrin and Phthalocyanine Chemistry ; Supramolecular Self-Assembly in Materials
Authors: Xueyi Chang | Muqing Chen | Tao Wei
Source: ChemPlusChem (review, 2024-07-04)
Field: Chemistry — Organic Chemistry

Precision Chemistry of Metallofullerenes and Graphene: Recent Advances Precision chemistry of synthetic carbon allotropes including fullerene and graphene, characterized by a well-controlled and spatially resolved addends bonding, has received widespread attention owing to its capability to tailor their physicochemical properties for high-end applications. In the context of fullerene, particularly endohedral metallofullerenes (EMFs), precision chemistry emphasizes the regioselective binding of a specific number of moieties to the fullerene cage. In the case of graphene, precision chemistry focuses on achieving precise patterning and tailored modifications. Inspired by their intriguing advantages, the precision chemistry of these two members has witnessed rapid advancements. While existing reviews have outlined advancements in the precision chemistry of EMFs and graphene, this review uniquely concentrates on the most recent progress. Finally, the prospects in this field, with a special focus on the potential for creating functional materials through strategically patterned binding of fullerene and graphene networks are envisioned. Graphene ; Nanotechnology ; Chemistry ; Materials science Fullerene Chemistry and Applications ; Carbon Nanotubes in Composites ; Graphene research and applications