jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Zohreh Hendi | Madhusudan K. Pandey | Saroj Kumar Kushvaha | Herbert W. Roesky
Source: Chemical Communications (review, 2024-01-01)
Field: Chemistry — Inorganic Chemistry

Recent progress in transition metal complexes featuring silylene as ligands Silylenes, divalent silicon(II) compounds, once considered highly reactive and transient species, are now widely employed as stable synthons in main-group and coordination chemistry for myriad applications. The synthesis of stable silylenes represents a major breakthrough, which led to extensive exploration of silylenes in stabilizing low-valent main-group elements and as versatile ligands in coordination chemistry and catalysis. In recent years, the exploration of transition metal complexes stabilized with silylene ligands has captivated significant research attention. This is due to their robust σ-donor characteristics and capacity to stabilize transition metals in low valent states. It has also been demonstrated that the transition metal complexes of silylenes are effective catalysts for hydroboration, hydrosilylation, hydrogenation, hydrogen isotope exchange reactions, and small molecule activation chemistry. This review article focuses on the recent progress in the synthesis and catalytic application of transition metal complexes of silylenes. Silylene ; Synthon ; Divalent ; Chemistry ; Transition metal ; Coordination complex ; Silicon ; Metal ; Combinatorial chemistry ; Group (periodic table) ; Nanotechnology ; Materials science ; Stereochemistry ; Organic chemistry ; Catalysis Synthesis and characterization of novel inorganic/organometallic compounds ; Organometallic Complex Synthesis and Catalysis ; Synthesis and Properties of Aromatic Compounds
Authors: Timothée Stoerkler | Gilles Ulrich | Pascal Retailleau | Adèle D. Laurent | Denis Jacquemin | Julien Massue
Source: Chemical Science (article, 2024-01-01)
Field: Chemistry — Physical and Theoretical Chemistry

Experimental and theoretical comprehension of ESIPT fluorophores based on a 2-(2′-hydroxyphenyl)-3,3′-dimethylindole (HDMI) scaffold Excited-State Intramolecular Proton Transfer (ESIPT) emission is associated with intense single or multiple fluorescence in the solid-state, along with enhanced photostability and sensitivity to the close environment. As a result, ESIPT probes are attractive candidates for ratiometric sensing of a variety of substrates. A new family of ESIPT fluorophores is described herein, inspired by the well-known 2-(2'hydroxyphenyl)benzazole (HBX) organic scaffold. The connection of 3,3'-dimethylindole (or 3<i>H</i>-indole) derivatives with phenol rings triggers the formation of novel 2-(2'-hydroxyphenyl)-3,3'-dimethylindole (HDMI) fluorophores, capable of stimuli-responsive ESIPT emission. This brand new family of dyes displays redshifted emission, as compared to HBX, along with an unprecedented acid/base-mediated stabilization of different rotamers, owing to supramolecular interactions with methyl groups. These compounds are therefore highly sensitive to external stimuli, such as the presence of acid or base, where protonated and deprotonated species have specific optical signatures. Moreover, a new pyridine-functionalized HDMI dye displays acid-sensitive AIE properties. The photophysical properties of all compounds have also been studied using <i>ab initio</i> calculations to support experiments in deciphering the nature of the various radiative transitions observed and the related excited rotameric species. Intramolecular force ; Sensitivity (control systems) ; Excited state ; Fluorescence ; Proton ; Photochemistry ; Chemistry ; State (computer science) ; Computer science ; Atomic physics ; Stereochemistry ; Physics ; Optics ; Algorithm Photochemistry and Electron Transfer Studies ; Luminescence and Fluorescent Materials ; Organic Light-Emitting Diodes Research
Authors: Mohammad‐Reza Azani | Azin Hassanpour
Source: Journal of Composites Science (article, 2024-10-25)
Field: Chemistry — Organic Chemistry

UV-Curable Polymer Nanocomposites: Material Selection, Formulations, and Recent Advances This study addresses the development of UV-curable polymer nanocomposites (PNCs), mainly based on acrylate, emphasizing material selection and formulation strategies that achieve efficient dispersion of the nanofillers (NFs). We begin by exploring various types of UV-curing coatings and delve deeper into their key components: monomers, oligomers, photoinitiators, fillers, and additives. Different types of components and examples are presented. Furthermore, this study delves into the critical importance of modifying NFs to tune the physical properties of the composite. It provides an overview of commonly used NFs and underscores the importance of surface modification (chemical and physical) as a pivotal technique for producing high-performance UV-curable PNCs. Additionally, various additives such as adhesion promoters, anti-foaming agents, and wetting and dispersing agents are discussed, emphasizing their functions within the formulation process. Different dispersion and blending methods are also discussed. The paper concludes by summarizing and presenting recent advancements in the formulation of UV-curable PNCs. This overview offers valuable insights to researchers and engineers working on the development of advanced materials. Materials science ; Nanocomposite ; Nanotechnology ; Selection (genetic algorithm) ; Polymer ; Polymer nanocomposite ; Polymer science ; Composite material ; Computer science ; Artificial intelligence Photopolymerization techniques and applications ; Silicone and Siloxane Chemistry ; Advanced Polymer Synthesis and Characterization
Authors: Maria Antonia Cassa | Piergiorgio Gentile | Joel Girón‐Hernández | Gianluca Ciardelli | Irene Carmagnola
Source: Biomaterials Science (review, 2024-01-01)
Field: Chemistry — Organic Chemistry

Smart self-defensive coatings with bacteria-triggered antimicrobial response for medical devices Bacterial colonization and biofilm formation on medical devices represent one of the most urgent and critical challenges in modern healthcare. These issues not only pose serious threats to patient health by increasing the risk of infections but also exert a considerable economic burden on national healthcare systems due to prolonged hospital stays and additional treatments. To address this challenge, there is a need for smart, customized biomaterials for medical device fabrication, particularly through the development of surface modification strategies that prevent bacterial adhesion and the growth of mature biofilms. This review explores three bioinspired approaches through which antibacterial and antiadhesive coatings can be engineered to exhibit smart, stimuli-responsive features. This responsiveness is greatly valuable as it provides the coatings with a controlled, on-demand antibacterial response that is activated only in the presence of bacteria, functioning as self-defensive coatings. Such coatings can be designed to release antibacterial agents or change their surface properties/conformation in response to specific stimuli, like changes in pH, temperature, or the presence of bacterial enzymes. This targeted approach minimizes the risk of developing antibiotic resistance and reduces the need for continuous, high-dose antibacterial treatments, thereby preserving the natural microbiome and further reducing healthcare costs. The final part of the review reports a critical analysis highlighting the potential improvements and future evolutions regarding antimicrobial self-defensive coatings and their validation. Antimicrobial ; Bacteria ; Microbiology ; Medical device ; Chemistry ; Nanotechnology ; Biology ; Medicine ; Materials science ; Biomedical engineering Antimicrobial agents and applications ; Antimicrobial Peptides and Activities ; Bacterial biofilms and quorum sensing
Authors: Neha Dubey | Sonali Gupta | Sandeep B. Shelar | K.C. Barick | Sudeshna Chandra
Source: Molecules (article, 2024-09-03)
Field: Materials Science — Materials Chemistry

Maximizing Upconversion Luminescence of Co-Doped CaF₂:Yb, Er Nanoparticles at Low Laser Power for Efficient Cellular Imaging Upconversion nanoparticles (UCNPs) are well-reported for bioimaging. However, their applications are limited by low luminescence intensity. To enhance the intensity, often the UCNPs are coated with macromolecules or excited with high laser power, which is detrimental to their long-term biological applications. Herein, we report a novel approach to prepare co-doped CaF<sub>2</sub>:Yb<sup>3+</sup> (20%), Er<sup>3+</sup> with varying concentrations of Er (2%, 2.5%, 3%, and 5%) at ambient temperature with minimal surfactant and high-pressure homogenization. Strong luminescence and effective red emission of the UCNPs were seen even at low power and without functionalization. X-ray diffraction (XRD) of UCNPs revealed the formation of highly crystalline, single-phase cubic fluorite-type nanostructures, and transmission electron microscopy (TEM) showed co-doped UCNPs are of ~12 nm. The successful doping of Yb and Er was evident from TEM-energy dispersive X-ray analysis (TEM-EDAX) and X-ray photoelectron spectroscopy (XPS) studies. Photoluminescence studies of UCNPs revealed the effect of phonon coupling between host lattice (CaF<sub>2</sub>), sensitizer (Yb<sup>3+</sup>), and activator (Er<sup>3+</sup>). They exhibited tunable upconversion luminescence (UCL) under irradiation of near-infrared (NIR) light (980 nm) at low laser powers (0.28-0.7 W). The UCL properties increased until 3% doping of Er<sup>3+</sup> ions, after which quenching of UCL was observed with higher Er<sup>3+</sup> ion concentration, probably due to non-radiative energy transfer and cross-relaxation between Yb<sup>3+</sup>-Er<sup>3+</sup> and Er<sup>3+</sup>-Er<sup>3+</sup> ions. The decay studies aligned with the above observation and showed the dependence of UCL on Er<sup>3+</sup> concentration. Further, the UCNPs exhibited strong red emission under irradiation of 980 nm light and retained their red luminescence upon internalization into cancer cell lines, as evident from confocal microscopic imaging. The present study demonstrated an effective approach to designing UCNPs with tunable luminescence properties and their capability for cellular imaging under low laser power. Materials science ; Photon upconversion ; Luminescence ; X-ray photoelectron spectroscopy ; Photoluminescence ; Analytical Chemistry (journal) ; Doping ; Nanoparticle ; Transmission electron microscopy ; Photochemistry ; Nanotechnology ; Optoelectronics ; Chemistry ; Chemical engineering Luminescence Properties of Advanced Materials ; bioluminescence and chemiluminescence research ; Radiation Detection and Scintillator Technologies
Authors: Zixing Zhang | Fancheng Meng | Xu Chi | Yang Jiao | Xue Bai | Xiaomeng Li | Fan Zhang
Source: Angewandte Chemie International Edition (article, 2024-11-12)
Field: Materials Science — Materials Chemistry

Diketopyrrolopyrrole‐Activated Dynamic Condensation Approach to Narrow‐Band Gap Vinylene‐Linked Covalent Organic Frameworks Vinyl units intrinsically featuring less steric, nonpolarity, and unsaturated character, are well-known π-bridge used in the synthesis of high-performance semiconducting materials. Two-dimensional (2D) vinylene-linked covalent organic frameworks (COFs) represent a promising class of π-conjugated structures, however, the range of available monomers for the reversible formation of carbon-carbon double bonds remains limited. In this study, a new class of 2D vinylene-linked COFs were synthesized using dimethyldiketopyrrolopyrrole (DM-DPP) as the key monomer. The strong electron deficiency of diketopyrrolopyrrole (DPP) makes its methyl substituents readily activated upon the cocatalysis of L-proline and 4-dimethylaminopyridine in aqueous solution to conduct dynamic condensation with tritopic aromatic aldehydes. The resulting COFs crystallized in an eclipsed AA stacking arrangement and featured abundant, regular nanochannels. Their robust vinyl DPP-linking mode enhanced donor-π-acceptor conjugation and promoted π-stacked alignment along the vertical direction. Consequently, the synthesized COFs exhibited band gaps as narrow as 1.02 eV and demonstrated excellent light-harvesting capability across the visible to near-infrared I (NIR-I) regions. Furthermore, the COFs could be converted into free-standing thin pellets through simple pressure casting, and show excellent photothermal response and cycling stability under different light sources. Materials science ; Covalent bond ; Stacking ; Conjugated system ; Monomer ; Steric effects ; Chemical engineering ; Photochemistry ; Nanotechnology ; Polymer ; Chemistry ; Organic chemistry Covalent Organic Framework Applications ; Metal-Organic Frameworks: Synthesis and Applications ; Conducting polymers and applications
Authors: Iwona Budziak-Wieczorek | Dominika Kaczmarczyk | Klaudia Rząd | Mariusz Gagoś | Andrzej Stepulak | Beata Myśliwa‐Kurdziel | Dariusz Karcz | Karolina Starzak | Gotard Burdziński | Monika Srebro‐Hooper | Arkadiusz Matwijczuk
Source: International Journal of Molecular Sciences (article, 2024-03-15)
Field: Chemistry — Physical and Theoretical Chemistry

Cooperativity of ESPT and Aggregation-Induced Emission Effects—An Experimental and Theoretical Analysis of a 1,3,4-Thiadiazole Derivative <i>4-[5-(Naphthalen-1-ylmethyl)-1,3,4-thiadiazol-2-yl]benzene-1,3-diol</i> (NTBD) was extensively studied through stationary UV-vis absorption and fluorescence measurements in various solvents and solvent mixtures and by first-principles quantum chemical calculations. It was observed that while in polar solvents (e.g., methanol) only a single emission band emerged; the analyzed 1,3,4-thiadiazole derivative was capable of producing dual fluorescence signals in low polarity solvents (e.g., <i>n</i>-hexane) and certain solvent mixtures (e.g., methanol/water). As clearly follows from the experimental spectroscopic studies and theoretical modeling, the specific emission characteristic of NTBD is triggered by the effect of enol → keto excited-state intramolecular proton transfer (ESIPT) that in the case of solvent mixture is reinforced by aggregation of thiadiazole molecules. Specifically, the restriction of intramolecular rotation (RIR) due to environmental hindrance suppresses the formation of non-emissive twisted intramolecular charge transfer (TICT) excited keto* states. As a result, this particular thiadiazole derivative is capable of simultaneously producing both ESIPT and aggregation-induced emission (AIE). Intramolecular force ; Chemistry ; Photochemistry ; Solvent ; Fluorescence ; Excited state ; Enol ; Derivative (finance) ; Solvent effects ; Methanol ; Molecule ; Computational chemistry ; Organic chemistry Photochemistry and Electron Transfer Studies ; Luminescence and Fluorescent Materials ; Porphyrin and Phthalocyanine Chemistry
Authors: Jieyu Yue | Jing‐Xian Luo | Zi‐Xian Pan | Ruizhi Zhang | Peng Yang | Qing Xu | Bo Tang
Source: Angewandte Chemie (article, 2024-04-12)
Field: Materials Science — Materials Chemistry

Regulating the Topology of Covalent Organic Frameworks for Boosting Overall H<sub>2</sub>O<sub>2</sub> Photogeneration Abstract Photocatalytic oxygen reduction reactions and water oxidation reactions are extremely promising green approaches for massive H 2 O 2 production. Nonetheless, constructing effective photocatalysts for H 2 O 2 generation is critical and still challenging. Since the network topology has significant impacts on the electronic properties of two dimensional (2D) polymers, herein, for the first time, we regulated the H 2 O 2 photosynthetic activity of 2D covalent organic frameworks (COFs) by topology. Through designing the linking sites of the monomers, we synthesized a pair of novel COFs with similar chemical components on the backbones but distinct topologies. Without sacrificial agents, TBD‐COF with cpt topology exhibited superior H 2 O 2 photoproduction performance (6085 and 5448 μmol g −1 h −1 in O 2 and air) than TBC‐COF with hcb topology through the O 2 ‐O 2 ⋅ − ‐H 2 O 2 , O 2 ‐O 2 ⋅ − ‐O 2 1 ‐H 2 O 2 , and H 2 O‐H 2 O 2 three paths. Further experimental and theoretical investigations confirmed that during the H 2 O 2 photosynthetic process, the charge carrier separation efficiency, O 2 ⋅ − generation and conversion, and the energy barrier of the rate determination steps in the three channels, related to the formation of *OOH, *O 2 1 , and *OH, can be well tuned by the topology of COFs. The current study enlightens the fabrication of high‐performance photocatalysts for H 2 O 2 production by topological structure modulation. Boosting (machine learning) ; Covalent bond ; Chemistry ; Topology (electrical circuits) ; Photochemistry ; Materials science ; Computer science ; Organic chemistry ; Engineering ; Artificial intelligence Covalent Organic Framework Applications ; Advanced Photocatalysis Techniques ; Metal-Organic Frameworks: Synthesis and Applications
Authors: Y. W. Bao | Xiongyi Liang | Hao Zhang | Xiuming Bu | Ziyan Cai | Yikai Yang | Di Yin | Yuxuan Zhang | L Chen | Yang Cheng | Xiulan Hu | Xiao Cheng Zeng | Johnny C. Ho | Ding Wang
Source: Advanced Energy Materials (article, 2024-07-18)
Field: Materials Science — Materials Chemistry

Revolutionizing Oxygen Evolution Reaction Catalysts: Efficient and Ultrastable Interstitial W‐Doped NiFe‐LDHs/MOFs through Controlled Topological Conversion of Metal‐Organic Frameworks Abstract Although metal‐organic frameworks (MOFs) show promise as electrocatalysts due to their unique intrinsic features, their activity and stability often fall short. Herein, NiFe‐MOFs is used as a model to introduce group VIB metalates (Na 2 WO 4 , Na 2 CrO 4 , and Na 2 MoO 4 ) into the topological conversion process of layer double hydroxide (LDHs)/MOFs, creating a series of interstitial VIB element‐doped LDHs/MOFs catalysts. The metalates engage in the alkaline hydrolysis process of MOF, generating LDHs on the MOF surface. Furthermore, altering the pH value in the reaction environment can modify the catalysts' morphology, dopant/LDHs content, and electronic structure. Consequently, the prepared interstitial W‐doped NiFe‐LDHs/MOFs catalyst displays superior catalytic performance, with overpotentials of only 250 mV at 500 mA cm −2 . Moreover, a homemade anion‐exchange membrane water electrolysis (AEMWE) system featuring the fabricated electrocatalyst as the anode can operate stably for 500 hours at 1 A cm −2 . The exceptional catalytic activity and stability stem from optimized intermediate adsorption/desorption behavior and the unique LDHs/MOFs nanostructure. This work not only highlights the potential of the catalysts for practical applications but also offers a new design approach for modulating MOFs using an alkaline hydrolysis strategy. Materials science ; Metal-organic framework ; Catalysis ; Doping ; Oxygen evolution ; Metal ; Chemical engineering ; Nanotechnology ; Oxygen ; Physical chemistry ; Optoelectronics ; Electrochemistry ; Metallurgy ; Organic chemistry ; Electrode ; Chemistry Catalytic Processes in Materials Science ; Electrocatalysts for Energy Conversion ; Advanced Photocatalysis Techniques
Authors: Nagore Izaguirre | Mikel Alberro | Xabier Erdocia | Jalel Labidi
Source: Journal of Energy Storage (article, 2024-01-09)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Kraft and organosolv lignin-activated carbon composites for supercapacitor electrode materials Lignin-activated carbon (AC) composites were employed as electrode active materials to develop more environmentally friendly Supercapacitor (SC) materials with enhanced properties. This way, the hydroquinone/quinone moieties present in lignin molecules added Faradaic processes to the system, and the capacitance of the active material increased, making it appropriate for future applications requiring more efficient and sustainable active materials. Lignin, a sustainable biobased aromatic polymer high in carbon content, was deposited on AC surface employing ultrasound (US) system, and for a better deposition, AC was treated with HNO3. Since the composition and properties of lignin can vary depending on their isolation process, two different types of lignin were used: Kraft lignin (KL) and Organosolv lignin (OL), and the effects on the chemical and electrochemical composition were deduced. Physicochemical, morphological, and electrochemical analyses were carried out on the lignin-AC composite to determine the optimum material combination and treatment process. It was observed that the acid treatment was effective in enhancing the functionality and porosity of the surface. Additionally, it improved the deposition of lignin and facilitated the formation of hierarchically porous structures on the surface of treated activated carbon (TAC), with different tendencies depending on the lignin employed. The creation of highly porous structures also resulted in enhanced electrochemical performance in materials. This validated the process, where eco-innovative technologies like US forces and employment of lignocellulosic biomass compounds like lignin were used as sustainable and efficient alternatives for obtaining electrochemically active materials. Organosolv ; Lignin ; Supercapacitor ; Materials science ; Chemical engineering ; Activated carbon ; Carbon fibers ; Electrochemistry ; Composite material ; Composite number ; Chemistry ; Organic chemistry ; Electrode Supercapacitor Materials and Fabrication ; Lignin and Wood Chemistry ; Biochemical and biochemical processes
Authors: Sheng He | Anji Ni | Sara T. Gebre | Rui Hang | James R. McBride | Alexey L. Kaledin | Wenxing Yang | Tianquan Lian
Source: Journal of the American Chemical Society (article, 2024-08-27)
Field: Materials Science — Materials Chemistry

Doping of Colloidal Nanocrystals for Optimizing Interfacial Charge Transfer: A Double-Edged Sword Doping of colloidal nanocrystals offers versatile ways to improve their optoelectronic properties, with potential applications in photocatalysis and photovoltaics. However, the precise role of dopants on the interfacial charge transfer properties of nanocrystals remains poorly understood. Here, we use a Cu-doped InP@ZnSe quantum dot as a model system to investigate the dopant effects on both the intrinsic photophysics and their interfacial charge transfer by combining time-resolved transient absorption and photoluminescent spectroscopic methods. Our results revealed that the Cu dopant can cause the generation of the self-trapped exciton, which prolongs the exciton lifetime from 48.3 ± 1.7 to 369.0 ± 4.3 ns, facilitating efficient charge separation to slow electron and hole acceptors. However, hole localization into the Cu site alters their energetic levels, slowing hole transfer and accelerating charge recombination loss. This double-edged sword role of dopants in charge transfer properties is important in the future design of nanocrystals for their optoelectronic and photocatalytic applications. Dopant ; Exciton ; Doping ; Nanocrystal ; Chemistry ; Photoluminescence ; Quantum dot ; Chemical physics ; Nanotechnology ; Charge (physics) ; Photovoltaics ; Charge carrier ; Photocatalysis ; Optoelectronics ; Materials science ; Condensed matter physics ; Photovoltaic system ; Physics Quantum Dots Synthesis And Properties ; Chalcogenide Semiconductor Thin Films ; Perovskite Materials and Applications