jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Suleman Suleman | Yi Zhang | Yunyang Qian | Jinwei Zhang | Zhongyuan Lin | Önder Metin | Zheng Meng | Hai‐Long Jiang
Source: Angewandte Chemie (article, 2023-11-29)
Field: Materials Science — Materials Chemistry

Turning on Singlet Oxygen Generation by Outer‐Sphere Microenvironment Modulation in Porphyrinic Covalent Organic Frameworks for Photocatalytic Oxidation Abstract Singlet oxygen ( 1 O 2 ) is ubiquitously involved in various photocatalytic oxidation reactions; however, efficient and selective production of 1 O 2 is still challenging. Herein, we reported the synthesis of nickel porphyrin‐based covalent organic frameworks (COFs) incorporating functional groups with different electron‐donating/‐withdrawing features on their pore walls. These functional groups established a dedicated outer‐sphere microenvironment surrounding the Ni catalytic center that tunes the activity of the COFs for 1 O 2 ‐mediated thioether oxidation. With the increase of the electron‐donating ability of functional groups, the modulated outer‐sphere microenvironment turns on the catalytic activity from a yield of nearly zero by the cyano group functionalized COF to an excellent yield of 98 % by the methoxy group functionalized one. Electronic property investigation and density‐functional theory (DFT) calculations suggested that the distinct excitonic behaviors attributed to the diverse band energy levels and orbital compositions are responsible for the different activities. This study represents the first regulation of generating reactive oxygen species (ROS) based on the strategy of outer‐sphere microenvironment modulation in COFs. Singlet oxygen ; Porphyrin ; Photocatalysis ; Covalent bond ; Chemistry ; Catalysis ; Photochemistry ; Density functional theory ; Oxygen ; Yield (engineering) ; Reactive oxygen species ; Materials science ; Computational chemistry ; Organic chemistry Covalent Organic Framework Applications ; Advanced Photocatalysis Techniques ; Metal-Organic Frameworks: Synthesis and Applications
Authors: Shin‐ichi Naya | Miwako Teranishi | Hiroaki Tada
Source: Catalysis Science & Technology (article, 2023-01-01)
Field: Materials Science — Materials Chemistry

Facile preparation of highly active zirconia-supported gold nanoparticle catalyst Au/insulating ZrO 2 prepared by a modified deposition precipitation (DP) method with a pre-step of long-time stirring of ZrO 2 NPs in HAuCl 4 solution shows catalytic activity for two electron-oxygen reduction much higher than Au/semiconducting metal oxides prepared by the normal DP method. Catalysis ; Cubic zirconia ; Nanoparticle ; Materials science ; Precipitation ; Chemical engineering ; Metal ; Deposition (geology) ; Colloidal gold ; Oxygen reduction reaction ; Nanotechnology ; Inorganic chemistry ; Chemistry ; Metallurgy ; Organic chemistry ; Electrochemistry ; Physical chemistry ; Electrode Catalytic Processes in Materials Science ; Electrocatalysts for Energy Conversion ; Nanomaterials for catalytic reactions
Authors: Monika Mutovska | Natali Simeonova | Stanimir Stoyanov | Yulian Zagranyarski | Silva Stanchovska | D. Marinova
Source: Materials (article, 2023-12-01)
Field: Chemistry — Organic Chemistry

Naphthalene Monoimides with Peri-Annulated Disulfide Bridge—Synthesis and Electrochemical Redox Activity Nowadays, organosulfur compounds provide new options in the development of full organic ion batteries. However, many drawbacks (such as kinetics limitations during the reversible oxidation of disulfides with cleavage of S-S bond, as well as solubility in non-aqueous electrolytes) make their commercialization difficult. Herein, a new concept for the design of organosulfur compounds with regulated redox properties and limited solubility is proposed. As a proof-of-concept, we designed <i>peri</i>-disulfo-substituted 1,8-naphthalimide derivatives, in which the alkyl chain length and halogen substituents (Cl or Br) at positions 3 and 6 are varied. The compounds were synthesized by an originally developed procedure starting from tetrahalonaphthalic anhydride via nucleophilic substitution at both <i>peri</i>-positions in the respective imide. Using ionic liquid electrolyte, it was found that the new <i>peri</i>-dithiolo-1,8-naphthalimides can participate in <i>n</i>- and <i>p</i>-type redox reactions at about 2.0 V and above 4.0 V vs. Li/Li<sup>+</sup>, respectively. The redox potentials are sensitive mainly to whether Cl or Br substituents are available in the molecule architecture, while the alkyl chain length determines the kinetics of the redox reactions. Among all compounds, the chloro-substituted compound with the shorter alkyl chain displays the best kinetics for both low- and high-voltage redox reactions. Redox ; Chemistry ; Organosulfur compounds ; Alkyl ; Electrochemistry ; Solubility ; Nucleophile ; Ionic liquid ; Imide ; Kinetics ; Combinatorial chemistry ; Organic chemistry ; Sulfur ; Electrode Chemical Synthesis and Reactions ; Advanced Battery Materials and Technologies ; Sulfur-Based Synthesis Techniques
Authors: Arshid Nabi | Christopher G. Jesudason | Jamal S. M. Sabir | Majid Rasool Kamli
Source: Pharmaceuticals (article, 2023-08-22)
Field: Chemistry — Organic Chemistry

Thermodynamic Insights of the Molecular Interactions of Dopamine (Neurotransmitter) with Anionic Surfactant in Non-Aqueous Media This study was aimed at establishing the interactions prevailing in an anionic surfactant, sodium dodecyl sulfate, and dopamine hydrochloride in an alcoholic (ethanol) media by using volumetric, conductometric, and tensiometric techniques. Various methods were utilized to estimate the critical micelle concentration (cmc) values at different temperatures. The entire methods yielded the same cmc values. The corresponding thermodynamic parameters viz. the standard free energy of micellization (Gmico), enthalpy of micellization (Hmico), and entropy of micellization (Smico) were predicted by applying the pseudo-phase separation model. The experimental density data at different temperatures (298.15 K, 303.15 K, 308.15 K, and 313.15 K) were utilized to estimate the apparent molar volumes (Vϕo) at an infinite dilution, apparent molar volumes (Vφcmc) at the critical micelle concentration, and apparent molar volumes (ΔVφm) upon micellization. Various micellar and interfacial parameters, for example, the surface excess concentration (Γmax), standard Gibbs free energy of adsorption at the interface (ΔGoad), and the minimum surface area per molecule (Amin), were appraised using the surface tension data. The results were used to interpret the intermolecular interactions prevailing in the mixed systems under the specified experimental conditions. Gibbs free energy ; Critical micelle concentration ; Standard molar entropy ; Chemistry ; Thermodynamics of micellization ; Gibbs isotherm ; Enthalpy ; Pulmonary surfactant ; Thermodynamics ; Surface tension ; Micelle ; Sodium dodecyl sulfate ; Aqueous solution ; Intermolecular force ; Adsorption ; Physical chemistry ; Standard enthalpy of formation ; Chromatography ; Molecule ; Organic chemistry Surfactants and Colloidal Systems ; Photochemistry and Electron Transfer Studies ; Protein Interaction Studies and Fluorescence Analysis
Authors: Waseem Arif | Ravi Kumar
Source: ChemistrySelect (article, 2023-12-19)
Field: Materials Science — Materials Chemistry

Single Pyrrole Unit Functionalized Electron Deficient Porphyrins and Their Metal Complexes: Synthesis, Structural, Spectral and Electrochemical Properties Abstract A family of electron‐deficient regioselective β ‐disubstituted meso ‐tetraphenylporphyrins, H 2 TPP(R) 2 (where R=trifluoromethyl (CF 3 ) and cyano (CN) and its metal complexes (Co(II), Ni(II), Cu(II) and Zn(II)) were synthesized from versatile precursor H 2 TPPBr 2 by palladium‐catalyzed trifluoromethylation and nucleophilic aromatic cyanation respectively. The absorption spectrum of H 2 TPP(CF 3 ) 2 and H 2 TPP(CN) 2 exhibited a notable shift towards longer wavelengths both in the Soret (Δλ ma x =16–17 nm) and longest wavelength band, Q x (0,0) (Δλ max =34–52 nm) as compared to precursor porphyrin, H 2 TPPBr 2 . The first ring reduction potential of H 2 TPP(CF 3 ) 2 and H 2 TPP(CN) 2 are centred at −0.69 and −0.68 respectively which show drastic anodic shift as compared to precursor H 2 TPPBr 2 (−1.01 V) and parent porphyrin H 2 TPP (−1.25 V). The anodic shift trend for first ring reduction potentials follows as H 2 TPP(CN) 2 &gt;H 2 TPP(CF 3 ) 2 &gt;H2TPP(Br) 2 &gt;H 2 TPP. Introducing two highly electron withdrawing substituents (CN and CF 3 ) at the single pyrrole unit of the porphyrin macrocycle via regioselective substitution has led to a significant reduction in the HOMO‐LUMO energy gap (0.15 V–0.39 V) in comparison to the precursor H 2 TPPBr 2 (2.08 V). The analysis of the crystal structures for ZnTPP(CN) 2 and H 2 TPP(CF 3 ) 2 revealed nearly planar and distinct saddle conformations respectively which are further supported by DFT calculations. Chemistry ; Regioselectivity ; Porphyrin ; Pyrrole ; Ring (chemistry) ; Dibenzothiophene ; Medicinal chemistry ; Electrochemistry ; Metal ; HOMO/LUMO ; Crystallography ; Photochemistry ; Catalysis ; Molecule ; Physical chemistry ; Organic chemistry Porphyrin and Phthalocyanine Chemistry ; Metal-Catalyzed Oxygenation Mechanisms ; Porphyrin Metabolism and Disorders
Authors: Mücahid Özcan | Cengiz Kaya | Figen Kaya
Source: Macromolecular Materials and Engineering (article, 2023-07-12)
Field: Materials Science — Biomaterials

An Optimization Study for the Electrospun Borate Ester Nanofibers as Light‐Weight, Flexible, and Affordable Neutron Shields for Personal Protection Abstract In this manuscript, a borate ester solution, as a precursor, is prepared by combining polyvinyl alcohol (PVA) and boric acid (BA). The precursor is then electrospun to form nanofibers. However, the addition of BA has a negative effect on the spinning behavior by changing the conductivity. The solution's quality is enhanced through use of additives such as glycerol, sodium chloride, and acetic acid. The effect of additives on the viscosity and conductivity of solutions, and their spinning behavior, is investigated. By adjusting electrospinning process variables and solution properties, nanofibers are produced. Fourier transform infrared (FT‐IR) analysis is performed to identify the formation of borate ester as a result of the reaction between PVA and BA. Thermal analysis is used to characterize the thermal stability of the fibers. Scanning electron microscopy (SEM) is used to examine the fiber morphology and diameter distribution. The findings are used to determine the best viscosity–conductivity windows for the production of electrospun borate ester nanofibers. Finally, the ability of optimized nanofibers to capture neutrons is evaluated using an Am‐Be neutron source and a BF 3 detector set up. The results of the measurements indicate that the incorporation of BA into PVA nanofibers can enhance their neutron shielding capabilities up to 7.3%. Nanofiber ; Materials science ; Electrospinning ; Polyvinyl alcohol ; Chemical engineering ; Thermal stability ; Scanning electron microscope ; Boric acid ; Nuclear chemistry ; Composite material ; Polymer chemistry ; Polymer ; Organic chemistry Electrospun Nanofibers in Biomedical Applications ; Polymer Nanocomposite Synthesis and Irradiation ; Environmental Engineering and Cultural Studies
Authors: Suset Barroso‐Solares | Javier Pinto | Coral Salvo‐Comino | Daniel Cuadra‐Rodríguez | C. Garcı́a | Miguel Ángel Rodríguez‐Pérez | Marı́a Luz Rodrı́guez-Méndez
Source: Applied Surface Science (article, 2023-07-17)
Field: Materials Science — Polymers and Plastics

Tuning the electrochemical response of PCL-PEDOT:PSS fibers-based sensors by gas dissolution foaming PEDOT:PSS ; Materials science ; Electrospinning ; Fiber ; Coating ; Microfiber ; Dissolution ; Cyclic voltammetry ; Composite material ; Polymer ; Porosity ; Conductive polymer ; Chemical engineering ; Electrochemistry ; Electrode ; Chemistry Conducting polymers and applications ; Advanced Sensor and Energy Harvesting Materials ; Supercapacitor Materials and Fabrication
Authors: Andreea Dumitrescu | Cătălin Maxim | Mihaela Badea | Arpad Mihai Rostas | Alexandra Ciorîţă | Alina Tîrşoaga | Rodica Olar
Source: International Journal of Molecular Sciences (article, 2023-12-05)
Field: Chemistry — Organic Chemistry

Decavanadate-Bearing Guanidine Derivatives Developed as Antimicrobial and Antitumor Species To obtain biologically active species, a series of decavanadates (Hpbg)<sub>4</sub>[H<sub>2</sub>V<sub>10</sub>O<sub>28</sub>]·6H<sub>2</sub>O (<b>1</b>) (Htbg)<sub>4</sub>[H<sub>2</sub>V<sub>10</sub>O<sub>28</sub>]·6H<sub>2</sub>O; (<b>2</b>) (Hgnd)<sub>2</sub>(Hgnu)<sub>4</sub>[V<sub>10</sub>O<sub>28</sub>]; (<b>3</b>) (Hgnu)<sub>6</sub>[V<sub>10</sub>O<sub>28</sub>]·2H<sub>2</sub>O; and (<b>4</b>) (pbg = 1-phenyl biguanide, tbg = 1-(<i>o</i>-tolyl)biguanide, gnd = guanidine, and gnu = guanylurea) were synthesized and characterized by several spectroscopic techniques (IR, UV-Vis, and EPR) as well as by single crystal X-ray diffraction. Compound (<b>1</b>) crystallizes in space group <i>P</i>-1 while (<b>3</b>) and (<b>4</b>) adopt the same centrosymmetric space group <i>P</i>21/n. The unusual signal identified by EPR spectroscopy was assigned to a charge-transfer π(O)→d(V) process. Both stability in solution and reactivity towards reactive oxygen species (O<sub>2</sub><sup>-</sup> and OH·) were screened through EPR signal modification. All compounds inhibited the development of <i>Escherichia coli</i>, <i>Pseudomonas aeruginosa</i>, <i>Staphylococcus aureus</i>, and <i>Enterococcus faecalis</i> bacterial strains in a planktonic state at a micromolar level, the most active being compound (<b>3</b>). However, the experiments conducted at a minimal inhibitory concentration (MIC) indicated that the compounds do not disrupt the biofilm produced by these bacterial strains. The cytotoxicity assayed against A375 human melanoma cells and BJ human fibroblasts by testing the viability, lactate dehydrogenase, and nitric oxide levels indicated compound (<b>1</b>) as the most active in tumor cells. Guanidine ; Antimicrobial ; Chemistry ; Combinatorial chemistry ; Bearing (navigation) ; Anti-Infective Agents ; Pharmacology ; Medicine ; Organic chemistry ; Computer science Synthesis and biological activity ; Synthesis and Characterization of Pyrroles ; Synthesis of Organic Compounds
Authors: Marco Reale | Alice Sciortino | M. Cannas | Ermelinda Maçôas | Arthur H. G. David | Carlos M. Cruz | Araceli G. Campaña | Fabrizio Messina
Source: Materials (article, 2023-01-15)
Field: Materials Science — Materials Chemistry

Atomically Precise Distorted Nanographenes: The Effect of Different Edge Functionalization on the Photophysical Properties down to the Femtosecond Scale Nanographenes (NGs) have been attracting widespread interest since they combine peculiar properties of graphene with molecular features, such as bright visible photoluminescence. However, our understanding of the fundamental properties of NGs is still hampered by the high degree of heterogeneity usually characterizing most of these materials. In this context, NGs obtained by atomically precise synthesis routes represent optimal benchmarks to unambiguously relate their properties to well-defined structures. Here we investigate in deep detail the optical response of three curved hexa-<i>peri</i>-hexabenzocoronene (HBC) derivatives obtained by atomically precise synthesis routes. They are constituted by the same graphenic core, characterized by the presence of a heptagon ring determining a saddle distortion of their sp<sup>2</sup> network, and differ from each other for slightly different edge functionalization. The quite similar structure allows for performing a direct comparison of their spectroscopic features, from steady-state down to the femtosecond scale, and precisely disentangling the role played by the different edge chemistry. Surface modification ; Femtosecond ; Materials science ; Context (archaeology) ; Photoluminescence ; Nanotechnology ; Graphene ; Chemical physics ; Enhanced Data Rates for GSM Evolution ; Scale (ratio) ; Optoelectronics ; Chemistry ; Physics ; Computer science ; Optics ; Physical chemistry ; Telecommunications Luminescence and Fluorescent Materials ; Carbon and Quantum Dots Applications ; Synthesis and Properties of Aromatic Compounds
Authors: Krishan Kumar | Maria Wächtler
Source: Nanomaterials (review, 2023-05-08)
Field: Materials Science — Materials Chemistry

Unravelling Dynamics Involving Multiple Charge Carriers in Semiconductor Nanocrystals The use of colloidal nanocrystals as part of artificial photosynthetic systems has recently gained significant attention, owing to their strong light absorption and highly reproducible, tunable electronic and optical properties. The complete photocatalytic conversion of water to its components is yet to be achieved in a practically suitable and commercially viable manner. To complete this challenging task, we are required to fully understand the mechanistic aspects of the underlying light-driven processes involving not just single charge carriers but also multiple charge carriers in detail. This review focuses on recent progress in understanding charge carrier dynamics in semiconductor nanocrystals and the influence of various parameters such as dimension, composition, and cocatalysts. Transient absorption spectroscopic studies involving single and multiple charge carriers, and the challenges associated with the need for accumulation of multiple charge carriers to drive the targeted chemical reactions, are discussed. Charge carrier ; Charge (physics) ; Semiconductor ; Nanotechnology ; Materials science ; Absorption (acoustics) ; Nanocrystal ; Chemical physics ; Effective nuclear charge ; Nanoparticle ; Ultrafast laser spectroscopy ; Quantum dot ; Optoelectronics ; Chemistry ; Physics ; Laser Quantum Dots Synthesis And Properties ; Advanced Photocatalysis Techniques ; Copper-based nanomaterials and applications
Authors: Lea Hegedüsová | Nadine Blaise | Lukáš F. Pašteka | Šimon Budzák | Miroslav Medveď | Juraj Filo | Bernard Mravec | Chavdar Slavov | Josef Wachtveitl | Anna Grabarz | Marek Cigáň
Source: Chemistry - A European Journal (article, 2023-11-13)
Field: Materials Science — Materials Chemistry

Enhancing the Potential of Fused Heterocycle‐Based Triarylhydrazone Photoswitches Triarylhydrazones represent an attractive class of photochromic compounds offering many interesting features including high molar absorptivity, good addressability, and extraordinary thermal stability. In addition, unlike most other hydrazone-based photoswitches, they effectively absorb light above 365 nm. However, previously prepared triaryhydrazones suffer from low quantum yields of the Z→E photoisomerization. Here, we have designed a new subclass of naphthoyl-benzothiazole hydrazones that balance the most beneficial features of previously reported naphthoyl-quinoline and benzoyl-pyridine triarylhydrazones. These preserve the attractive absorption characteristics, exhibit higher thermal stability of the metastable form than the former and enhance the rate of the Z→E photoisomerization compared to the later, as a result of the weakening of the intramolecular hydrogen bonding between the hydrazone hydrogen and the benzothiazole moiety. Introducing the benzothiazole motif extends the tunability of the photochromic behaviour of hydrazone-based switches. Benzothiazole ; Photochromism ; Photoisomerization ; Photochemistry ; Intramolecular force ; Moiety ; Chemistry ; Thermal stability ; Triphenylamine ; Hydrazone ; Isomerization ; Materials science ; Organic chemistry Photochromic and Fluorescence Chemistry ; Photoreceptor and optogenetics research ; Luminescence and Fluorescent Materials
Authors: Ancheng Da | Yanan Chu | J Krach | Yunbo Liu | Younggeun Park | Somin Eunice Lee
Source: Sensors (article, 2023-03-04)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Optical Penetration of Shape-Controlled Metallic Nanosensors across Membrane Barriers Precise nanostructure geometry that enables the optical biomolecular delivery of nanosensors to the living intracellular environment is highly desirable for precision biological and clinical therapies. However, the optical delivery through membrane barriers utilizing nanosensors remains difficult due to a lack of design guidelines to avoid inherent conflict between optical force and photothermal heat generation in metallic nanosensors during the process. Here, we present a numerical study reporting significantly enhanced optical penetration of nanosensors by engineering nanostructure geometry with minimized photothermal heating generation for penetrating across membrane barriers. We show that by varying the nanosensor geometry, penetration depths can be maximized while heat generated during the penetration process can be minimized. We demonstrate the effect of lateral stress induced by an angularly rotating nanosensor on a membrane barrier by theoretical analysis. Furthermore, we show that by varying the nanosensor geometry, maximized local stress fields at the nanoparticle-membrane interface enhanced the optical penetration process by four-fold. Owing to the high efficiency and stability, we anticipate that precise optical penetration of nanosensors to specific intracellular locations will be beneficial for biological and therapeutic applications. Nanosensor ; Penetration (warfare) ; Materials science ; Nanotechnology ; Membrane ; Metal ; Engineering ; Chemistry ; Metallurgy ; Operations research Gold and Silver Nanoparticles Synthesis and Applications ; Plasmonic and Surface Plasmon Research ; Advanced biosensing and bioanalysis techniques
Authors: A.V. Nikitin | A. Campargue | A. E. Protasevich | M. Rey | Keeyoon Sung | Vladimir G. Tyuterev
Source: Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy (article, 2023-05-25)
Field: Chemistry — Spectroscopy

Analysis of experimental spectra of phosphine in the Tetradecad range near 2.3 μm using ab initio calculations Ab initio ; Spectral line ; Range (aeronautics) ; Phosphine ; Ab initio quantum chemistry methods ; Computational chemistry ; Materials science ; Molecular physics ; Atomic physics ; Physics ; Chemistry ; Quantum mechanics ; Molecule ; Organic chemistry Spectroscopy and Laser Applications ; Atmospheric Ozone and Climate ; Analytical Chemistry and Chromatography
Authors: Marko Dunatov | Andreas Puškarić | Lidija Androš Dubraja
Source: Journal of Materials Chemistry C (article, 2023-01-01)
Field: Materials Science — Materials Chemistry

Multi-stimuli responsive (<scp>l</scp>-tartrato)oxovanadium(<scp>v</scp>) complex salt with ferroelectric switching and thermistor properties A complex salt of tetraethylammonium cations and anions consisting of an inorganic {V 4 O 8 } core chelated with l -tartaric acid undergoes structural transformations triggered by changes in humidity and temperature, giving rise to switchable properties. Tartaric acid ; Tetraethylammonium ; Salt (chemistry) ; Materials science ; Thermistor ; Ferroelectricity ; Humidity ; Chelation ; Chemical engineering ; Inorganic chemistry ; Crystallography ; Organic chemistry ; Chemistry ; Potassium ; Metallurgy ; Optoelectronics ; Meteorology Polyoxometalates: Synthesis and Applications ; Metal-Organic Frameworks: Synthesis and Applications ; Vanadium and Halogenation Chemistry