jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Pritam J. Morankar | Rutuja U. Amate | Manesh A. Yewale | Chan‐Wook Jeon
Source: Crystals (article, 2024-11-28)
Field: Materials Science — Polymers and Plastics

Effect of Annealing Temperature on Morphology and Electrochromic Performance of Electrodeposited WO₃ Thin Films The purpose of this study was to investigate the effect of annealing temperature on the structural, morphological, and electrochemical properties of tungsten trioxide (WO3) films, fabricated via electrodeposition and annealed at 50 °C, 250 °C, and 450 °C. Structural analysis using X-ray diffraction (XRD) revealed temperature-induced modifications, transitioning from amorphous to crystalline phases. Morphological studies by field emission scanning electron microscopy (FESEM) demonstrated an increase in grain size with temperature (31 nm, 48 nm, and 53 nm) and the formation of cracks at higher annealing temperatures. Electrochemical characterization showed that the WO3 film annealed at 250 °C exhibited superior redox activity, enhanced ion diffusion, and excellent reversibility. Optical studies highlighted its exceptional performance, with 79.35% optical modulation, a coloration efficiency of 97.91 cm2/C, and rapid switching times (9.8 s for coloration and 7.5 s for bleaching). Furthermore, long-term cycling tests confirmed minimal degradation after 5000 cycles, demonstrating durability. This work provides a comprehensive understanding of the annealing temperature’s impact on WO3 films and underscores the novelty of achieving optimal electrochromic (EC) performance through temperature tuning, advancing the design of energy-efficient smart materials. Electrochromism ; Annealing (glass) ; Materials science ; Morphology (biology) ; Thin film ; Optoelectronics ; Nanotechnology ; Chemical engineering ; Composite material ; Chemistry ; Electrode Transition Metal Oxide Nanomaterials ; Gas Sensing Nanomaterials and Sensors ; Conducting polymers and applications
Authors: Naoya Haraguchi | Taisei Kurosaki | Sayaka Uchida
Source: Physical Chemistry Chemical Physics (article, 2024-01-01)
Field: Materials Science — Materials Chemistry

Small luminescent silver clusters stabilized in porous crystalline solids Subnanometric or small metal clusters (SMCs) have been extensively researched due to their unique electronic, optical, catalytic, and magnetic properties, which differ from those of bulk samples. Among the SMCs, silver (Ag) clusters have received significant interest due to their affordability and unique luminescent properties. Currently, two major approaches, gas-phase and liquid-phase synthesis, have been employed to obtain Ag clusters with precise control of size and structure. More recently, attention has been directed toward the utilization of porous crystalline solids such as metal-organic frameworks (MOFs), zeolites, and porous ionic crystals (PICs) to synthesize and stabilize Ag clusters. In this review, we aim to provide a comprehensive overview of the synthesis, structures, and luminescent properties of Ag clusters in porous crystalline solids. Luminescence ; Porosity ; Materials science ; Cluster (spacecraft) ; Phase (matter) ; Ionic bonding ; Chemical engineering ; Metal ; Porous medium ; Nanotechnology ; Chemical physics ; Chemistry ; Ion ; Organic chemistry ; Composite material ; Metallurgy ; Optoelectronics Nanocluster Synthesis and Applications ; Advanced Nanomaterials in Catalysis ; Metal-Organic Frameworks: Synthesis and Applications
Authors: Tibor Dubaj | Stefano Vecchio Ciprioti | Jacopo Tirillò | Fabrizio Sarasini
Source: Thermochimica Acta (article, 2024-05-02)
Field: Materials Science — Biomaterials

Thermal stability of binary and ternary biodegradable polymer blends assessed by isoconversional kinetic analysis • Blends of PLA with PHBV and PBAT undergo stepwise thermal decomposition. • Mathematical deconvolution analysis was performed on integral curves. • Deconvoluted curves were separately analyzed by isoconversional method. • Effect of blending on thermal stability was assessed from kinetic parameters. Here we report on kinetic analysis of thermal degradation of polymer blends based on incremental isoconversional method coupled with mathematical deconvolution of thermogravimetric curves based on Fraser–Suzuki peak function. The measured kinetic envelope was decomposed into contributions approximately corresponding to degradation of each constituent of a polymer blend. Kinetic parameters from isoconversional analysis were further used for estimating the effect of blending on thermal stability of the constituents. Compared to routinely used parameters such as degradation onset temperature or DTG-peak temperature, the deconvolution analysis allows to determine stability of all components in a mixture regardless of their relative content. Here we also show that deconvolution analysis can be carried out directly on integral α ( T ) curves, thus bypassing the work with differential data dα / dt . Isoconversional analysis of deconvoluted α ( T ) curves allows to calculate various parameters for assessing the potentially accelerating or inhibiting effect on thermal degradation, for example, by means of decomposition half-time t 0.5 . The results can be made more robust by utilizing relative criteria for stability such as t 0.5 (blend)/ t 0.5 (neat polymer). Using this approach, detrimental effect of PHBV and PBAT on thermal stability of PLA above 300 °C was confirmed. On the other hand, stability of PHBV in both binary and ternary mixtures was improved compared to neat polymer. Ternary operation ; Thermal stability ; Polymer blend ; Materials science ; Thermal analysis ; Kinetic energy ; Polymer ; Thermodynamics ; Chemical engineering ; Polymer chemistry ; Thermal ; Chemistry ; Organic chemistry ; Composite material ; Copolymer ; Physics biodegradable polymer synthesis and properties ; Thermal and Kinetic Analysis ; Polymer crystallization and properties
Authors: Robert Green-Warren | Andrew Fassler | Abigail T. Juhl | Noah McAllister | Andrew Huth | Maxim Arkhipov | Michael J. Grzenda | S. Rahman Pejman | Michael F. Durstock | Jonathan P. Singer
Source: RSC Applied Polymers (article, 2024-01-01)
Field: Materials Science — Polymers and Plastics

Self-limiting electrospray deposition (SLED) of porous polyimide coatings as effective lithium-ion battery separator membranes An exploded view of a Li-ion coin cell with an electrosprayed polyimide separator deposited onto an NMC electrode. Polyimide ; Separator (oil production) ; Membrane ; Limiting ; Materials science ; Chemical engineering ; Electrospray ; Porosity ; Ion ; Lithium-ion battery ; Deposition (geology) ; Nanotechnology ; Composite material ; Battery (electricity) ; Chemistry ; Organic chemistry ; Engineering Synthesis and properties of polymers ; Fuel Cells and Related Materials ; Membrane Separation and Gas Transport
Authors: Kabir O. Oyedotun | Katlego Makgopa | Thabo T.I. Nkambule | Mkhulu Mathe | Kabir O. Otun | Bhekie B. Mamba
Source: Polymers (article, 2024-06-28)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Nanostructured Carbon Fibres (NCF): Fabrication and Application in Supercapacitor Electrode A facile interconnected nanofibre electrode material derived from polybenzimidazol (PBI) was fabricated for a supercapacitor using a centrifugal spinning technique. The PBI solution in a mixture of dimethyl acetamide (DMA) and N, N-dimethylformamide (DMF) was electrospun to an interconnection of fine nanofibres. The as-prepared material was characterised by using various techniques, which include scanning electron microscopy (SEM), X-ray diffractometry (XRD), Raman, X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller (BET) among others. The specific surface area of the interconnected NCF material was noticed to be around 49 m<sup>2</sup> g<sup>-1</sup>. Electrochemical properties of the material prepared as a single-electrode are methodically studied by adopting cyclic voltammetry, electrochemical impedance spectroscopy, and constant-current charge-discharge techniques. A maximum specific capacitance of 78.4 F g<sup>-1</sup> was observed for the electrode at a specific current of 0.5 A g<sup>-1</sup> in a 2.5 M KNO<sub>3</sub> solution. The electrode could also retain 96.7% of its initial capacitance after a 5000 charge-discharge cycles at 5 A g<sup>-1</sup>. The observed capacitance and good cycling stability of the electrode are supported by its specific surface area, pore volume, and conductivity. The results obtained for this material indicate its potential as suitable candidate electrode for supercapacitor application. Supercapacitor ; Materials science ; Cyclic voltammetry ; Electrode ; X-ray photoelectron spectroscopy ; Capacitance ; Dielectric spectroscopy ; Specific surface area ; Raman spectroscopy ; Chemical engineering ; Scanning electron microscope ; Analytical Chemistry (journal) ; Electrochemistry ; Nanotechnology ; Composite material ; Chemistry ; Organic chemistry Supercapacitor Materials and Fabrication ; Electrochemical sensors and biosensors ; Electrospun Nanofibers in Biomedical Applications
Authors: Dóra Hegedüs | Nikoletta Szemerédi | Krisztina Petrinca | Róbert Berkecz | Gabriella Spengler | István Szatmári
Source: Molecules (article, 2024-09-03)
Field: Chemistry — Organic Chemistry

Synthesis of Tumor Selective Indole and 8-Hydroxyquinoline Skeleton Containing Di-, or Triarylmethanes with Improved Cytotoxic Activity The reaction between glycine-type aminonaphthol derivatives substituted with 2- or 1-naphthol and indole or 7-azaindole has been tested. Starting from 2-naphthol as a precursor, the reaction led to the formation of ring-closed products, while in the case of a 1-naphthol-type precursor, the desired biaryl ester was isolated. The synthesis of a bifunctional precursor starting from 5-chloro-8-hydroxyquinoline, morpholine, and ethyl glyoxylate via modified Mannich reaction is reported. The formed Mannich base <b>10</b> was subjected to give bioconjugates with indole and 7-azaindole. The effect of the aldehyde component and the amine part of the Mannich base on the synthetic pathway was also investigated. In favor of having a preliminary overview of the structure-activity relationships, the derivatives have been tested on cancer and normal cell lines. In the case of bioconjugate <b>16</b>, as the most powerful scaffold in the series bearing indole and a 5-chloro-8-hydroxyquinoline skeleton, a potent toxic activity against the resistant Colo320 colon adenocarcinoma cell line was observed. Furthermore, this derivative was selective towards cancer cell lines showing no toxicity on non-tumor fibroblast cells. Chemistry ; Indole test ; Mannich base ; Bioconjugation ; Morpholine ; Aldehyde ; Amine gas treating ; Stereochemistry ; Combinatorial chemistry ; Organic chemistry ; Catalysis Synthesis of Indole Derivatives ; Synthesis and biological activity ; Synthesis and Biological Activity
Authors: Oddný Björgvinsdóttir | Stephen J. Ferguson | Bergthóra S. Snorradóttir | Thorarinn Gudjonsson | Karin Wuertz‐Kozak
Source: Materials Today Bio (article, 2024-04-18)
Field: Materials Science — Biomaterials

The influence of physical and spatial substrate characteristics on endothelial cells Cardiovascular diseases are a main cause of death worldwide, leading to a growing demand for medical devices to treat this patient group. Central to the engineering of such devices is a good understanding of the biology and physics of cell-surface interactions. In existing blood-contacting devices, such as vascular grafts, the interaction between blood, cells, and material is one of the main limiting factors for their long-term durability. An improved understanding of the material's chemical- and physical properties as well as its structure all play a role in how endothelial cells interact with the material surface. This review provides an overview of how different surface structures influence endothelial cell responses and what is currently known about the underlying mechanisms that guide this behavior. The structures reviewed include decellularized matrices, electrospun fibers, pillars, pits, and grated surfaces. Decellularization ; Limiting ; Durability ; Substrate (aquarium) ; Nanotechnology ; Materials science ; Medicine ; Tissue engineering ; Cell biology ; Biomedical engineering ; Biology ; Engineering ; Mechanical engineering ; Composite material Electrospun Nanofibers in Biomedical Applications ; Tissue Engineering and Regenerative Medicine ; 3D Printing in Biomedical Research
Authors: Liqin Tang | Yixing Xu | Jianglong He | Gaiqun Huang | Xueping Jiang | Yuqi Li | Hao Li | Ran Zhang | Zhongzheng Gui
Source: ACS Medicinal Chemistry Letters (article, 2024-10-18)
Field: Chemistry — Organic Chemistry

1-Deoxynojirimycin Derivative Containing Tegafur Induced HCT-116 Cell Apoptosis through Mitochondrial Dysfunction and Oxidative Stress Pathway Three 1-deoxynojirimycin (DNJ) derivatives (named <b>C4</b>-<b>C6</b>) including DNJ and tegafur (TGF) were designed and synthesized, and their antiproliferative effects were investigated. <b>C4</b>-<b>C6</b>, especially <b>C6</b>, exerted good lipophilicity, α-glucosidase inhibitory activity, and antitumor effects. Mechanism studies indicated that <b>C6</b> significantly induced cell apoptosis and S-phase block and inhibited migration of HCT-116 cells. Besides, <b>C6</b> induced mitochondrial damage by decreasing the mitochondrial membrane potential, improving the accumulation of ROS, upregulating the expression of Bax, and downregulating Bcl-2. Moreover, <b>C6</b> induced excessive production of ROS to trigger oxidative stress, resulting in an increase in the level of MDA and NO, a decrease in the content of GSH and SOD, and an overexpression of Nrf2. Furthermore, <b>C6</b> induced DNA damage by down-regulating the expression of thymidylate synthase. These results indicated that <b>C6</b> is a potential antitumor agent and kills HCT-116 cells through DNA damage, mitochondrial dysfunction, and oxidative stress. Oxidative stress ; Apoptosis ; Mitochondrion ; Derivative (finance) ; Chemistry ; Cancer research ; Pharmacology ; Oxidative phosphorylation ; Biochemistry ; Medicine ; Bioinformatics ; Biology ; Business Synthesis and biological activity ; Genomics, phytochemicals, and oxidative stress ; Synthesis and Biological Evaluation
Authors: Henric Steffenfauseweh | Yury V. Vishnevskiy | Beate Neumann | Hans‐Georg Stammler | Bas de Bruin | Rajendra S. Ghadwal
Source: Chemistry - A European Journal (article, 2024-03-04)
Field: Chemistry — Organic Chemistry

N‐Heterocyclic Carbene Analogues of Wittig Hydrocarbon N-Heterocyclic carbene (NHC) analogues of Wittig hydrocarbon, [(NHC)(Stil)(NHC)] (3a-c) (NHC = SIPr (1a) = C[N(Dipp)CH<sub>2</sub>]<sub>2</sub>, Dipp = 2,6-iPr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>; IPr (1b) = C[N(Dipp)CH]<sub>2</sub>; Me-IPr (1c) = C[N(Dipp)CMe]<sub>2</sub> and Stil = C<sub>6</sub>H<sub>4</sub>CHCHC<sub>6</sub>H<sub>4</sub>) have been reported as crystalline solids. 3a-c are prepared by two-electron reductions of the corresponding bis-1,3-imidazoli(ni)um bromides [(NHC)(Stil)NHC)](Br)<sub>2</sub> (2a-c) with KC<sub>8</sub> in >94 % yields. 2a-c are accessible by the nickel catalyzed direct C-C coupling of NHCs (1a-c) with (E)-4,4'-dibromostilbene. One-electron oxidation of 3a,b yields the corresponding radical cations [(NHC)(Stil)NHC)]B(C<sub>6</sub>F<sub>5</sub>)<sub>4</sub> 4a,b. All compounds have been characterized by UV-Vis/NMR/EPR spectroscopy as well as 2a, 3a, and 3b by single crystal X-ray diffraction. The electronic structures of representative systems have been analyzed by quantum chemical calculations. Wittig reaction ; Carbene ; Hydrocarbon ; Chemistry ; Organic chemistry ; Catalysis N-Heterocyclic Carbenes in Organic and Inorganic Chemistry ; Synthesis and characterization of novel inorganic/organometallic compounds ; Synthetic Organic Chemistry Methods
Authors: Mohammad Ali Bakhtiari | Mohammad Fathi | Fatemeh Abdolmohammadi | Seyed Mohammad Ali Hoseinian | Siavash Sepahi | Pooya Hooshyar | Mohammad Taghi Ahmadian | Ahmad Assempour
Source: Scientific Reports (article, 2024-08-06)
Field: Chemistry — Organic Chemistry

Investigation the behavior of different fullerenes on graphene surface In the present study, the regime of motion of fullerene molecules on graphene substrate in a specific temperature range is investigated. The potential energy of fullerene molecules is analyzed using classical molecular dynamics methods. Fullerene molecules C36, C50, C60, C76, C80, and C90 are selected due to spherical shapes of different sizes and good motion performance in previous studies. Analysis of the motion regime at different temperatures is one of the main objectives of this study. To achieve this aim, the translational and rotational movements of fullerene molecules are studied independently. In the first step of the investigation, Lennard-Jone's potential energy of fullerene molecules is calculated. Subsequently, the motion regime of different fullerenes is classified based on their displacement and diffusion coefficient. Findings indicate C60 is not appropriate in all conditions. However, C90 and C76 molecules are found to be appropriate candidates in most cases in different conditions. As far as a straight-line movement is considered, the deviation of fullerene molecules is compared by their angular velocities. Although C60 has a lower angular velocity due to its symmetrical shape, it may not move well due to its low diffusion coefficient. Overall, our study helps to understand the performance of different fullerene molecules on graphene substrate and find their possible applications, especially as wheels in nanomachine or nanocarrier structures. Fullerene ; Molecule ; Graphene ; Materials science ; Molecular dynamics ; Chemical physics ; Diffusion ; Rotational diffusion ; Rotation around a fixed axis ; Substrate (aquarium) ; Nanotechnology ; Computational chemistry ; Chemistry ; Physics ; Thermodynamics ; Classical mechanics ; Organic chemistry Fullerene Chemistry and Applications ; Carbon Nanotubes in Composites ; Molecular Junctions and Nanostructures
Authors: Minghao Liu | Cheng‐Xing Cui | Shuai Yang | Xiubei Yang | Xuewen Li | Jun He | Qing Xu | Gaofeng Zeng
Source: Angewandte Chemie (article, 2024-02-26)
Field: Materials Science — Materials Chemistry

Elaborate Modulating Binding Strength of Intermediates via Three‐component Covalent Organic Frameworks for CO<sub>2</sub>Reduction Reaction Abstract The catalytic performance for electrocatalytic CO 2 reduction reaction (CO 2 RR) depends on the binding strength of the reactants and intermediates. Covalent organic frameworks (COFs) have been adopted to catalyze CO 2 RR, and their binding abilities are tuned via constructing donor‐acceptor (DA) systems. However, most DA COFs have single donor and acceptor units, which caused wide‐range but lacking accuracy in modulating the binding strength of intermediates. More elaborate regulation of the interactions with intermediates are necessary and challenge to construct high‐efficiency catalysts. Herein, the three‐component COF with D‐A‐A units was first constructed by introducing electron‐rich diarylamine unit, electron‐deficient benzothiazole and Co‐porphyrin units. Compared with two‐component COFs, the designed COF exhibit elevated electronic conductivity, enhanced reducibility, high efficiency charge transfer, further improving the electrocatalytic CO 2 RR performance with the faradic efficiency of 97.2 % at −0.8 V and high activity with the partial current density of 27.85 mA cm −2 at −1.0 V which exceed other two‐component COFs. Theoretical calculations demonstrate that catalytic sites in three‐component COF have suitable binding ability of the intermediates, which are benefit for formation of *COOH and desorption of *CO. This work offers valuable insights for the advancement of multi‐component COFs, enabling modulated charge transfer to improve the CO 2 RR activity. Chemistry ; Catalysis ; Covalent organic framework ; Covalent bond ; Electron transfer ; Porphyrin ; Desorption ; Combinatorial chemistry ; Reaction intermediate ; Benzothiazole ; Component (thermodynamics) ; Acceptor ; Photochemistry ; Physical chemistry ; Organic chemistry ; Adsorption ; Thermodynamics Covalent Organic Framework Applications ; CO2 Reduction Techniques and Catalysts ; Metal-Organic Frameworks: Synthesis and Applications
Authors: Guili Zhao | Florian Lochon | Kassiogé Dembélé | Ileana Florea | Alexandre Baron | Razvigor Ossikovski | Aleix G. Güell
Source: ACS Applied Nano Materials (article, 2024-02-27)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Rapid and Facile Synthesis of Gold Trisoctahedrons for Surface-Enhanced Raman Spectroscopy and Refractive Index Sensing Au trisoctahedrons (TOHs) with sharp tips and high-index facets have exceptional properties for diverse applications, such as plasmon-enhanced spectroscopies, catalysis, sensing, and biomedicine. However, the synthesis of Au TOHs remains challenging, and most reported synthetic methods are time-consuming or involve complex steps, hindering the exploration of their potential applications. Herein, we present a facile and fast approach to prepare Au TOHs with high uniformity and good control over the final size and shape, all within less than 10 min of synthesis, for surface-enhanced Raman spectroscopy (SERS) and refractive index sensing. The size of the Au TOHs can be easily tailored over a wide range, from 39 to 268 nm, allowing a tuning of the plasmon resonance at wavelengths from visible to near-infrared regions. The exposed facets of the Au TOHs can also be varied by controlling the growth temperatures. The wide tunability of size and exposed facets of Au TOHs can greatly broaden the range of their applications. We have also encapsulated Au TOHs with zeolite imidazolate framework (ZIF-8), obtaining core-shell hybrid structures. With the ability to tune Au TOH size, we further assessed their SERS performances in function of their size by detecting 2-NaT in solution, exhibiting enhancement factors of the order of 10<sup>5</sup> with higher values when the LSPR is blue-shifted from the laser excitation wavelength. Au TOHs have been also compared for refractive index sensing applications against Au nanospheres, revealing Au TOHs as better candidates. Overall, this facile and fast method for synthesizing Au TOHs with tunable size and exposed facets simplifies the path toward the exploration of properties and applications of this highly symmetrical and high-index nanostructure. Raman spectroscopy ; Surface-enhanced Raman spectroscopy ; Materials science ; Refractive index ; Spectroscopy ; Index (typography) ; Nanotechnology ; Optics ; Analytical Chemistry (journal) ; Optoelectronics ; Raman scattering ; Chemistry ; Computer science ; Organic chemistry ; Physics Gold and Silver Nanoparticles Synthesis and Applications ; Nanocluster Synthesis and Applications ; Advanced Nanomaterials in Catalysis