jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Asmaa A. Abdelrahman | Samar H. Bendary | Sawsan A. Mahmoud
Source: Diamond and Related Materials (article, 2023-02-01)
Field: Materials Science — Materials Chemistry

Synthesis and electrochemical properties of Ni Al LDH@RGO hierarchical nanocomposite as a potential counter electrode in dye sensitized solar cells Graphene ; Materials science ; Dielectric spectroscopy ; Cyclic voltammetry ; Dye-sensitized solar cell ; Auxiliary electrode ; Raman spectroscopy ; Scanning electron microscope ; Fourier transform infrared spectroscopy ; High-resolution transmission electron microscopy ; Chemical engineering ; Analytical Chemistry (journal) ; Nuclear chemistry ; Nanotechnology ; Electrochemistry ; Electrolyte ; Electrode ; Chemistry ; Transmission electron microscopy ; Composite material ; Organic chemistry Layered Double Hydroxides Synthesis and Applications ; TiO2 Photocatalysis and Solar Cells ; Advanced Photocatalysis Techniques
Authors: Rohini Kumari | Daphika S. Dkhar | Pranjal Chandra
Source: Microchemical Journal (article, 2023-05-08)
Field: Chemistry — Electrochemistry

Electrochemically nanotuned surface comprising 3D bimetallic dendrites fabricated on MWCNT for detection of 1,4-dioxane in water Bimetallic strip ; Detection limit ; Nanosensor ; Materials science ; Tap water ; Carbon nanotube ; Electrochemistry ; Pollutant ; Electrochemical gas sensor ; Nanotechnology ; Chemical engineering ; Electrode ; Chemistry ; Chromatography ; Environmental science ; Metallurgy ; Metal ; Environmental engineering Electrochemical Analysis and Applications ; Electrochemical sensors and biosensors ; Analytical Chemistry and Sensors
Authors: Shipeng Wan | Wenlong Zhao | Ke‐Ke Tan | Haiyan Lu | Meng Li | Chuan‐Feng Chen
Source: Chemical Engineering Journal (article, 2023-05-17)
Field: Chemistry — Organic Chemistry

Axially chiral thermally activated delayed fluorescence emitters enabled by molecular engineering towards high-performance circularly polarized OLEDs OLED ; Luminescence ; Common emitter ; Materials science ; Photoluminescence ; Optoelectronics ; Quantum efficiency ; Diode ; Fluorescence ; Axial symmetry ; Optics ; Nanotechnology ; Physics Synthesis and Properties of Aromatic Compounds ; Organic Light-Emitting Diodes Research ; Luminescence and Fluorescent Materials
Authors: Meng-Fan Wang | Yun‐Hu Deng | Yu‐Xuan Hong | Jiahui Gu | Yong-Yong Cao | Qi Liu | Pierre Braunstein | Jian‐Ping Lang
Source: Nature Communications (article, 2023-11-27)
Field: Materials Science — Materials Chemistry

In situ observation of a stepwise [2 + 2] photocycloaddition process using fluorescence spectroscopy Using highly sensitive and selective in situ techniques to investigate the dynamics of intermediates formation is key to better understand reaction mechanisms. However, investigating the early stages of solid-state reactions/transformations is still challenging. Here we introduce in situ fluorescence spectroscopy to observe the evolution of intermediates during a two-step [2 + 2] photocycloaddition process in a coordination polymer platform. The structural changes and kinetics of each step under ultraviolet light irradiation versus time are accompanied by the gradual increase-decrease of intensity and blue-shift of the fluorescence spectra from the crystals. Monitoring the fluorescence behavior using a laser scanning confocal microscope can directly visualize the inhomogeneity of the photocycloaddition reaction in a single crystal. Theoretical calculations allow us to rationalize the fluorescence behavior of these compounds. We provide a convenient strategy for visualizing the solid-state photocycloaddition dynamics using fluorescence spectroscopy and open an avenue for kinetic studies of a variety of fast reactions. Fluorescence ; Spectroscopy ; Fluorescence spectroscopy ; In situ ; Photochemistry ; Chemistry ; Ultraviolet ; Kinetics ; Materials science ; Chemical physics ; Optics ; Organic chemistry ; Physics ; Optoelectronics Machine Learning in Materials Science ; Radical Photochemical Reactions ; Photochromic and Fluorescence Chemistry
Authors: Chigozie Charity Okwuwa | Fatmawati Adam | Farhan Mohd Said | Michael E. Ries
Source: Journal of Cleaner Production (review, 2023-10-06)
Field: Materials Science — Biomaterials

Cellulose dissolution for edible biocomposites in deep eutectic solvents: A review Cosmetics ; Eutectic system ; Dissolution ; Cellulose ; Solubility ; Biochemical engineering ; Materials science ; Organic chemistry ; Chemistry ; Engineering Advanced Cellulose Research Studies ; Nanocomposite Films for Food Packaging ; Ionic liquids properties and applications
Authors: Prakash Kshirsagar | Valeria De Matteis | Sudipto Pal | S. Shiv Shankar
Source: Nanomaterials (article, 2023-09-01)
Field: Materials Science — Materials Chemistry

Silver–Gold Alloy Nanoparticles (AgAu NPs): Photochemical Synthesis of Novel Biocompatible, Bimetallic Alloy Nanoparticles and Study of Their In Vitro Peroxidase Nanozyme Activity Facile synthesis of metal nanoparticles with controlled physicochemical properties using environment-friendly reagents can open new avenues in biomedical applications. Nanomaterials with controlled physicochemical properties have opened new prospects for a variety of applications. In the present study, we report a single-step photochemical synthesis of ~5 nm-sized silver (Ag) and gold (Au) nanoparticles (NPs), and Ag-Au alloy nanoparticles using L-tyrosine. The physicochemical and surface properties of both monometallic and bimetallic NPs were investigated by analytical, spectroscopic, and microscopic techniques. Our results also displayed an interaction between L-tyrosine and surface atoms that leads to the formation of AgAu NPs by preventing the growth and aggregation of the NPs. This method efficiently produced monodispersed NPs, with a narrow-sized distribution and good stability in an aqueous solution. The cytotoxicity assessment performed on breast cancer cell lines (MCF-7) revealed that the biofriendly L-tyrosine-capped AgNPs, AuNPs, and bimetallic AgAu NPs were biocompatible. Interestingly, AgAu NPs have also unveiled controlled cytotoxicity, cell viability, and in vitro peroxidase nanozyme activity reliant on metal composition and surface coating. Bimetallic strip ; Nanomaterials ; Nanoparticle ; Nanotechnology ; Materials science ; Chemistry ; Nanochemistry ; Alloy ; Noble metal ; Chemical engineering ; Metal ; Organic chemistry Advanced Nanomaterials in Catalysis ; Nanocluster Synthesis and Applications ; Nanoparticles: synthesis and applications
Authors: Abdul Shakoor Shar | Ningning Wang | Tianyu Chen | Xiaoying Zhao | Yunxuan Weng
Source: Polymers (article, 2023-10-11)
Field: Materials Science — Biomaterials

Development of PLA/Lignin Bio-Composites Compatibilized by Ethylene Glycol Diglycidyl Ether and Poly (ethylene glycol) Diglycidyl Ether Poly (lactic acid) (PLA) is a promising green substitute for conventional petroleum-based plastics in a variety of applications. However, the wide application of PLA is still limited by its disadvantages, such as slow crystallization rate, inadequate gas barrier, thermal degradation, etc. In this study, lignin (1, 3, 5 PHR) was incorporated into PLA to improve the thermal, mechanical, and barrier properties of PLA. Two low-viscosity epoxy resins, ethylene glycol diglycidyl ether (EGDE) and poly (ethylene glycol) diglycidyl ether (PEGDE), were used as compatibilizers to enhance the performance of the composites. The addition of lignin improved the onset degradation temperature of PLA by up to 15 °C, increased PLA crystallinity, improved PLA tensile strength by approximately 15%, and improved PLA oxygen barrier by up to 58.3%. The addition of EGDE and PEGDE both decreased the glass transition, crystallization, and melting temperatures of the PLA/lignin composites, suggesting their compatabilizing and plasticizing effects, which contributed to improved oxygen barrier properties of the PLA/lignin composites. The developed PLA/lignin composites with improved thermal, mechanical, and gas barrier properties can potentially be used for green packaging applications. Materials science ; Diglycidyl ether ; Ethylene glycol ; Lignin ; Crystallinity ; Glass transition ; Crystallization ; Composite material ; Ether ; Ultimate tensile strength ; Chemical engineering ; Polymer ; Epoxy ; Polymer chemistry ; Organic chemistry ; Chemistry ; Bisphenol A biodegradable polymer synthesis and properties ; Lignin and Wood Chemistry ; Carbon dioxide utilization in catalysis
Authors: Giulia Vozzolo | Marta Ximenis | Daniele Mantione | Mercedes Fernández | Haritz Sardón
Source: ACS Macro Letters (article, 2023-11-01)
Field: Materials Science — Polymers and Plastics

Thermally Reversible Organocatalyst for the Accelerated Reprocessing of Dynamic Networks with Creep Resistance The industrial implementation of covalent adaptable networks hinges on the delicate task of achieving rapid bond exchange activation at specific temperatures while ensuring a sufficiently slow exchange at working temperatures to avoid irreversible deformation. In this pursuit, latent catalysts offer a potential solution, allowing for spatiotemporal control of dynamic exchange in vitrimer networks. However, the irreversible nature of their activation has led to undesired creep deformation after multiple cycles of reprocessing. In this work, we demonstrate that a tetraphenylborate tetramethyl guanidinium salt (<b>TPB:TMG</b>) undergoes a reversible thermal dissociation, releasing free <b>TMG</b>. This thermally reversible organocatalyst can be readily introduced as an additive in industrially relevant materials such as disulfide-containing polyurethane networks (PU) that undergo disulfide exchange in the presence of a base catalyst. In contrast with a free-base-catalyzed process, we demonstrate the dual benefit of adding the thermally reversible <b>TPB:TMG</b> in preventing creep at lower temperatures and also enabling reprocessability of disulfide-containing PU networks at elevated temperatures. The remarkable reversibility of this thermally activated catalyst allows for multiple reprocessing cycles while effectively maintaining a creep-free state at service temperature. Creep ; Covalent bond ; Dissociation (chemistry) ; Catalysis ; Materials science ; Dynamic covalent chemistry ; Isocyanate ; Chemistry ; Chemical engineering ; Polyurethane ; Molecule ; Organic chemistry ; Composite material Polymer composites and self-healing ; Oxidative Organic Chemistry Reactions ; Marine Sponges and Natural Products
Authors: Rajpratap Kshatriya
Source: ACS Omega (review, 2023-05-11)
Field: Chemistry — Organic Chemistry

Recent Advancement in H<sub>8</sub>–BINOL Catalyzed Asymmetric Methodologies H<sub>8</sub>-BINOL, a partially reduced form of BINOL, is widely employed in a broad array of organocatalyzed asymmetric methodologies. Over the last 25 years, asymmetric organocatalysis has witnessed an incredible improvement, and an advancement still continues to get a single enantio-enriched product. The broad-spectrum applications of H<sub>8</sub>-BINOL organocatalyst in C-C bond formation, C-heteroatom bond construction, name reactions, pericyclic reactions, and one pot and multicomponent reaction are attracting the attention of researchers. A diversified unique H<sub>8</sub>-BINOL-based catalyst has been synthesized and screened for catalytic activity. In this Review we frame out the H<sub>8</sub>-BINOL catalyzed novel discoveries from the last two decades. Organocatalysis ; Pericyclic reaction ; Catalysis ; Enantioselective synthesis ; Heteroatom ; Chemistry ; Combinatorial chemistry ; Organic chemistry ; Ring (chemistry) Asymmetric Synthesis and Catalysis ; Asymmetric Hydrogenation and Catalysis ; Chemical Synthesis and Reactions
Authors: Robert W. Jones | Alexander J. Auty | Guanzhi Wu | Petter Persson | Martin V. Appleby | Dimitri Chekulaev | Craig R. Rice | Julia A. Weinstein | Paul I. P. Elliott | Paul A. Scattergood
Source: Journal of the American Chemical Society (article, 2023-05-24)
Field: Materials Science — Materials Chemistry

Direct Determination of the Rate of Intersystem Crossing in a Near-IR Luminescent Cr(III) Triazolyl Complex A detailed understanding of the dynamics of photoinduced processes occurring in the electronic excited state is essential in informing the rational design of photoactive transition-metal complexes. Here, the rate of intersystem crossing in a Cr(III)-centered spin-flip emitter is directly determined through the use of ultrafast broadband fluorescence upconversion spectroscopy (FLUPS). In this contribution, we combine 1,2,3-triazole-based ligands with a Cr(III) center and report the solution-stable complex [Cr(btmp)<sub>2</sub>]<sup>3+</sup> (btmp = 2,6-<i>bis</i>(4-phenyl-1,2,3-triazol-1-yl-methyl)pyridine) (<b>1</b><sup><b>3+</b></sup>), which displays near-infrared (NIR) luminescence at 760 nm (τ = 13.7 μs, ϕ = 0.1%) in fluid solution. The excited-state properties of <b>1</b><sup><b>3+</b></sup> are probed in detail through a combination of ultrafast transient absorption (TA) and femtosecond-to-picosecond FLUPS. Although TA spectroscopy allows us to observe the evolution of phosphorescent excited states within the doublet manifold, more significantly and for the first time for a complex of Cr(III), we utilize FLUPS to capture the short-lived fluorescence from initially populated quartet excited states immediately prior to the intersystem crossing process. The decay of fluorescence from the low-lying <sup>4</sup>MC state therefore allows us to assign a value of (823 fs)<sup>-1</sup> to the rate of intersystem crossing. Importantly, the sensitivity of FLUPS to only luminescent states allows us to disentangle the rate of intersystem crossing from other closely associated excited-state events, something which has not been possible in the spectroscopic studies previously reported for luminescent Cr(III) systems. Intersystem crossing ; Chemistry ; Excited state ; Photochemistry ; Phosphorescence ; Ultrafast laser spectroscopy ; Internal conversion ; Luminescence ; Singlet fission ; Triplet state ; Fluorescence ; Spectroscopy ; Singlet state ; Atomic physics ; Optoelectronics ; Spectral line ; Materials science ; Physics ; Optics Lanthanide and Transition Metal Complexes ; Magnetism in coordination complexes ; Metal complexes synthesis and properties
Authors: Ben Nanzai | Akimitsu Mochizuki | Yusuke Wakikawa | Yusuke Masuda | Tadashi Oshio | Kazuhiro Yagishita
Source: Ultrasonics Sonochemistry (article, 2023-03-07)
Field: Materials Science — Materials Chemistry

Sonoluminescence intensity and ultrasonic cavitation temperature in organic solvents: Effects of generated radicals Ultrasonic cavitation in organic solvents remains poorly understood in contrast with aqueous systems, largely because of complexities related to solvent decomposition. In this study, we sonicated different types of organic solvents (i.e. linear alkanes, aliphatic alcohols, aromatic alcohols, and acetate esters) under argon saturation. The average temperature of the cavitation bubbles was estimated using the methyl radical recombination method. We also discuss the effects of the physical properties of the solvents, such as vapor pressure and viscosity, on the cavitation temperature. The average cavitation bubble temperature and sonoluminescence intensity were higher in organic solvents with lower vapor pressure; for aromatic alcohols, these values were particularly high. It was found that the specific high sonoluminescence intensities and average cavitation temperatures exhibited in aromatic alcohols are caused by the highly resonance-stable generated radicals. The results obtained in this study are very useful for acceleration of sonochemical reaction in organic solvents, which are indispensable for organic synthesis and material synthesis. Sonoluminescence ; Cavitation ; Radical ; Sonochemistry ; Chemistry ; Vapor pressure ; Solvent ; Sonication ; Photochemistry ; Aqueous solution ; Decomposition ; Organic chemistry ; Thermodynamics ; Chromatography Ultrasound and Cavitation Phenomena ; Ultrasound and Hyperthermia Applications ; Photoacoustic and Ultrasonic Imaging
Authors: Sami El Deeb | Khalid Abdelsamad | Maria Kristina Parr
Source: Pharmaceuticals (article, 2023-10-19)
Field: Chemistry — Spectroscopy

Greener and Whiter Analytical Chemistry Using Cyrene as a More Sustainable and Eco-Friendlier Mobile Phase Constituent in Chromatography Cyrene (dihydrolevoglucosenone) was evaluated for the first time as a potential sustainable mobile phase solvent in reversed-phase chromatography. As a benign biodegradable solvent, Cyrene is an attractive replacement to classical non-green organic chromatographic solvents such as acetonitrile and a modifier, co-eluent to known green solvents such as ethanol. Compared to ethanol, Cyrene is less toxic, non-flammable, biobased, biodegradable, and a cheaper solvent. A fire safety spider chart was generated to compare the properties of Cyrene to ethanol and show its superiority as a greener solvent. Cyrene's behavior, advantages, and drawbacks in reversed-phase chromatography, including the cut-off value of 350 nm, elution power, selectivity, and effect on the column, were investigated using a model drug mixture of moxifloxacin and metronidazole. A monolithic C<sub>18</sub> (100 × 4.6 mm) column was used as a stationary phase. Different ratios of Cyrene: ethanol with an aqueous portion of sodium acetate buffer mobile phases were tested. A mobile phase consisting of Cyrene: ethanol: 0.1 M sodium acetate buffer pH 4.25 (8:13:79, <i>v</i>/<i>v</i>/<i>v</i>) was selected as the most suitable mobile phase system for separating and simultaneously determining metronidazole and moxifloxacin. The greenness and whiteness of the method were evaluated using the qualitative green assessment tool AGREE and the white analytical chemistry assessment tool RGB12. Further potentials of Cyrene as a solvent or modifier in normal phase chromatography, liquid chromatography-mass spectrometry, and supercritical fluid chromatography are discussed. Chromatography ; Chemistry ; Solvent ; Supercritical fluid chromatography ; Column chromatography ; High-performance liquid chromatography ; Acetonitrile ; Organic chemistry Analytical Chemistry and Chromatography ; Crystallization and Solubility Studies ; Chromatography in Natural Products
Authors: David Dalmau | Esteban P. Urriolabeitia
Source: Molecules (review, 2023-03-15)
Field: Materials Science — Materials Chemistry

Luminescence and Palladium: The Odd Couple The synthesis, photophysical properties, and applications of highly fluorescent and phosphorescent palladium complexes are reviewed, covering the period 2018-2022. Despite the fact that the Pd atom appears closely related with an efficient quenching of the fluorescence of different molecules, different synthetic strategies have been recently optimized to achieve the preservation and even the amplification of the luminescent properties of several fluorophores after Pd incorporation. Beyond classical methodologies such as orthopalladation or the use of highly emissive ligands as porphyrins and related systems (for instance, biladiene), new concepts such as AIE (Aggregation Induced Emission) in metallacages or in coordination-driven supramolecular compounds (CDS) by restriction of intramolecular motions (RIM), or complexes showing TADF (Thermally Activated Delayed Fluorescence), are here described and analysed. Without pretending to be comprehensive, selected examples of applications in areas such as the fabrication of lighting devices, biological markers, photodynamic therapy, or oxygen sensing are also here reported. Palladium ; Intramolecular force ; Luminescence ; Fluorescence ; Phosphorescence ; Quenching (fluorescence) ; Photochemistry ; Supramolecular chemistry ; Molecule ; Chemistry ; Nanotechnology ; Materials science ; Combinatorial chemistry ; Optoelectronics ; Catalysis ; Stereochemistry ; Organic chemistry ; Optics ; Physics Luminescence and Fluorescent Materials ; Molecular Sensors and Ion Detection ; Organic Light-Emitting Diodes Research
Authors: J. Woods | Lucía Gallego | Amira Maisch | Dominik Renggli | Corrado Cuocci | Olivier Blacque | Gunther Steinfeld | Andres Kaech | Bernhard Spingler | Andreas Vargas Jentzsch | Michel Rickhaus
Source: Nature Communications (article, 2023-08-07)
Field: Materials Science — Biomaterials

Saddles as rotational locks within shape-assisted self-assembled nanosheets Two-dimensional (2D) materials are a key target for many applications in the modern day. Self-assembly is one approach that can bring us closer to this goal, which usually relies upon strong, directional interactions instead of covalent bonds. Control over less directional forces is more challenging and usually does not result in as well-defined materials. Explicitly incorporating topography into the design as a guiding effect to enhance the interacting forces can help to form highly ordered structures. Herein, we show the process of shape-assisted self-assembly to be consistent across a range of derivatives that highlights the restriction of rotational motion and is verified using a diverse combination of solid state analyses. A molecular curvature governed angle distribution nurtures monomers into loose columns that then arrange to form 2D structures with long-range order observed in both crystalline and soft materials. These features strengthen the idea that shape becomes an important design principle leading towards precise molecular self-assembly and the inception of new materials. Curvature ; Nanotechnology ; Process (computing) ; Self-assembly ; Rotation around a fixed axis ; Range (aeronautics) ; Computer science ; Molecular dynamics ; Motion (physics) ; Materials science ; Topology (electrical circuits) ; Chemical physics ; Physics ; Geometry ; Classical mechanics ; Chemistry ; Computational chemistry ; Artificial intelligence ; Mathematics Supramolecular Self-Assembly in Materials ; Supramolecular Chemistry and Complexes ; Polydiacetylene-based materials and applications
Authors: Marvin Langlais | Nicolas Baulu | Séverin Dronet | Charlotte Dire | F. Jean-Baptiste-Dit-Dominique | David F. Albertini | Franck D’Agosto | Damien Montarnal | Christophe Boisson
Source: Angewandte Chemie International Edition (article, 2023-08-29)
Field: Materials Science — Biomaterials

Multiblock Copolymers Based on Highly Crystalline Polyethylene and Soft Poly(ethylene‐<i>co</i>‐butadiene) Segments: Towards Polyolefin Thermoplastic Elastomers Block copolymers based on polyethylene (PE) and ethylene butadiene rubber (EBR) were obtained by successive controlled coordinative chain transfer polymerization (CCTP) of a mixture of ethylene and butadiene (80/20) and pure ethylene. EBR-b-PE diblock copolymers were synthesized using the {Me<sub>2</sub> Si(C<sub>13</sub> H<sub>8</sub> )<sub>2</sub> Nd(BH<sub>4</sub> )<sub>2</sub> Li(THF)}<sub>2</sub> complex in combination with n-butyl,n-octyl magnesium (BOMAG) used as both the alkylating and chain transfer agent (CTA). Triblock and multiblock copolymers featuring highly semi-crystalline PE hard segments and soft EBR segments were further obtained by the development of a bimetallic CTA, the pentanediyl-1,5-di(magnesium bromide) (PDMB). These new block copolymers undergo crystallization-driven organization into lamellar structures and exhibit a variety of mechanical properties, including excellent extensibility and elastic recovery in the case of triblock and multiblock copolymers. Copolymer ; Thermoplastic elastomer ; Materials science ; Polyolefin ; Polymer chemistry ; Polyethylene ; Elastomer ; Lamellar structure ; Ethylene ; Polymerization ; Chemical engineering ; Polymer ; Composite material ; Chemistry ; Organic chemistry ; Catalysis biodegradable polymer synthesis and properties ; Organometallic Complex Synthesis and Catalysis ; Polymer crystallization and properties