jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Anastasia A. Sherstneva | Tatiana S. Demina | Ana P. F. Monteiro | Т. А. Акопова | Christian Grandfils | Ange B. Ilangala
Source: Polymers (review, 2022-03-24)
Field: Materials Science — Biomaterials

Biodegradable Microparticles for Regenerative Medicine: A State of the Art and Trends to Clinical Application Tissue engineering and cell therapy are very attractive in terms of potential applications but remain quite challenging regarding the clinical aspects. Amongst the different strategies proposed to facilitate their implementation in clinical practices, biodegradable microparticles have shown promising outcomes with several advantages and potentialities. This critical review aims to establish a survey of the most relevant materials and processing techniques to prepare these micro vehicles. Special attention will be paid to their main potential applications, considering the regulatory constraints and the relative easiness to implement their production at an industrial level to better evaluate their application in clinical practices. Regenerative medicine ; Risk analysis (engineering) ; Nanotechnology ; Computer science ; Biochemical engineering ; Systems engineering ; Management science ; Engineering ; Medicine ; Materials science ; Stem cell Electrospun Nanofibers in Biomedical Applications ; 3D Printing in Biomedical Research ; Pickering emulsions and particle stabilization
Authors: Fatima Hammoud | Akram Hijazi | Malika Ibrahim‐Ouali | Jacques Lalevée | Frédéric Dumur
Source: European Polymer Journal (article, 2022-04-23)
Field: Chemistry — Organic Chemistry

Chemical engineering around the 5,12-dihydroindolo[3,2-a]carbazole scaffold: Fine tuning of the optical properties of visible light photoinitiators of polymerization Carbazole ; Polymerization ; Photopolymer ; Photochemistry ; Materials science ; Chromophore ; Radical polymerization ; Cyclic voltammetry ; Thiophene ; Polymer chemistry ; Chemistry ; Polymer ; Organic chemistry ; Electrochemistry ; Physical chemistry Photopolymerization techniques and applications ; Photochromic and Fluorescence Chemistry ; Dental materials and restorations
Authors: Bin Mu | Zhelin Zhang | Xiangnan Hao | Tianshu Ma | Wei Tian
Source: Macromolecules (article, 2022-06-23)
Field: Materials Science — Materials Chemistry

Positional Isomerism-Mediated Copolymerization Realizing the Continuous Luminescence Color-Tuning of Liquid-Crystalline Polymers Liquid crystals with color-tunable light emission are important for a variety of applications; however, achieving multicolor light-emitting liquid crystals whose emission colors can be fine-tuned remains challenging because the limited derivatization of mesogenic fluorophores disfavors the diversity of the emission. Here, we present a positional isomerism-mediated copolymerization strategy to obtain liquid-crystalline polymers with continuous luminescence color-tuning ability. The introduced α–/β-cyanostilbene positional isomers possess very similar molecular structures, thus reducing the risk of assembly heterogeneity and facilitating the formation of a homogeneous and consistent liquid crystal mesophase. Meanwhile, a significant electronic effect was caused for fluorophores with positional isomerization, allowing the efficient tuning of emission colors via copolymerization. Especially with a gradual change in the composition of the copolymers, the emission color shift behaved in a continuous manner from blue to green. These cyanostilbene-based liquid-crystalline polymers also showed reversible photochromic fluorescence switching ability. This approach highlights the value of positional isomers to prepare color-tunable solid-state light-emitting materials, allowing control and fine-tuning of the emission property while maintaining the ordered assembly ability. Mesogen ; Luminescence ; Mesophase ; Copolymer ; Materials science ; Liquid crystal ; Polymer ; Photochromism ; Structural isomer ; Isomerization ; Fluorescence ; Photochemistry ; Polyfluorene ; Liquid crystalline ; Chemical physics ; Nanotechnology ; Chemistry ; Organic chemistry ; Optoelectronics ; Optics ; Catalysis Luminescence and Fluorescent Materials ; Photochromic and Fluorescence Chemistry ; Synthesis and Properties of Aromatic Compounds
Authors: Yi Yu | Zewei Liu | Xiaofei Chen | Shu‐Jun Liu | Chongxiong Duan | Hongxia Xi
Source: Nano Materials Science (article, 2022-10-06)
Field: Chemistry — Inorganic Chemistry

Water-based synthesis of nanoscale hierarchical metal-organic frameworks: Boosting adsorption and catalytic performance The combination of nano sizes, large pore sizes and green synthesis is recognized as one of the most crucial and challenging problems in constructing metal-organic frameworks (MOFs). Herein, a water-based strategy is proposed for the synthesis of nanoscale hierarchical MOFs (NH-MOFs) with high crystallinity and excellent stability. This approach allows the morphology and porosity of MOFs to be fine tuned, thereby enabling the nanoscale crystal generation and a well-defined hierarchical system. The aqueous solution facilitates rapid nucleation kinetics, and the introduced modulator acts as a deprotonation agent to accelerate the deprotonation of the organic ligand as well as a structure-directing agent (SDA) to guide the formation of hierarchical networks. The as-synthesized NH-MOFs (NH-ZIF-67) were assessed as efficient adsorbents and heterogeneous catalysts to facilitate the diffusion of guest molecules, outperforming the parent microZIF-67. This study focuses on understanding the NH-MOF growth rules, which could allow tailor-designing NH-MOFs for various functions. Metal-organic framework ; Nanoscopic scale ; Materials science ; Nucleation ; Catalysis ; Nanotechnology ; Adsorption ; Crystallinity ; Deprotonation ; Aqueous solution ; Molecule ; Chemical engineering ; Chemistry ; Organic chemistry Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications ; Membrane Separation and Gas Transport
Authors: James R. Pankhurst | Laia Castilla-Amorós | Dragos Stoian | Jan Vávra | Valeria Mantella | Petru P. Albertini | Raffaella Buonsanti
Source: Journal of the American Chemical Society (article, 2022-06-30)
Field: Materials Science — Materials Chemistry

Copper Phosphonate Lamella Intermediates Control the Shape of Colloidal Copper Nanocrystals Understanding the structure and behavior of intermediates in chemical reactions is the key to developing greater control over the reaction outcome. This principle is particularly important in the synthesis of metal nanocrystals (NCs), where the reduction, nucleation, and growth of the reaction intermediates will determine the final size and shape of the product. The shape of metal NCs plays a major role in determining their catalytic, photochemical, and electronic properties and, thus, the potential applications of the material. In this work, we demonstrate that layered coordination polymers, called lamellae, are reaction intermediates in Cu NC synthesis. Importantly, we discover that the lamella structure can be fine-tuned using organic ligands of different lengths and that these structural changes control the shape of the final NC. Specifically, we show that short-chain phosphonate ligands generate lamellae that are stable enough at the reaction temperature to facilitate the growth of Cu nuclei into anisotropic Cu NCs, being primarily triangular plates. In contrast, lamellae formed from long-chain ligands lose their structure and form spherical Cu NCs. The synthetic approach presented here provides a versatile tool for the future development of metal NCs, including other anisotropic structures. Chemistry ; Nucleation ; Copper ; Lamella (surface anatomy) ; Metal ; Colloid ; Reaction intermediate ; Nanocrystal ; Phosphonate ; Catalysis ; Anisotropy ; Nanotechnology ; Crystallography ; Chemical engineering ; Organic chemistry ; Materials science ; Composite material Nanocluster Synthesis and Applications ; Copper-based nanomaterials and applications ; Nanomaterials for catalytic reactions
Authors: Daniela Cappello | Francis L. Buguis | Joe B. Gilroy
Source: ACS Omega (article, 2022-08-26)
Field: Materials Science — Materials Chemistry

Tuning the Properties of Donor–Acceptor and Acceptor–Donor–Acceptor Boron Difluoride Hydrazones <i>via</i> Extended π-Conjugation Molecular materials with π-conjugated donor-acceptor (D-A) and acceptor-donor-acceptor (A-D-A) electronic structures have received significant attention due to their usage in organic photovoltaic materials, in organic light-emitting diodes, and as biological imaging agents. Boron-containing molecular materials have been explored as electron-accepting units in compounds with D-A and A-D-A properties as they often exhibit unique and tunable optoelectronic and redox properties. Here, we utilize Stille cross-coupling chemistry to prepare a series of compounds with boron difluoride hydrazones (BODIHYs) as acceptors and benzene, thiophene, or 9,9-dihexylfluorene as donors. BODIHYs with D-A and A-D-A properties exhibited multiple reversible redox waves, solid-state emission with photoluminescence quantum yields up to 10%, and aggregation-induced emission (AIE). Optical band gaps (or highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gaps) determined for these compounds (2.02-2.25 eV) agree well with those determined from cyclic voltammetry experiments (2.05-2.42 eV). The optoelectronic properties described herein are rationalized with density functional theory calculations that support the interpretation of the experimental findings. This work provides a foundation of understanding that will allow for the consideration of D-A and A-D-A BODIHYs to be incorporated into applications (<i>e.g.</i>, organic electronics) where fine-tuning of band gaps is required. HOMO/LUMO ; Acceptor ; Photochemistry ; Materials science ; Band gap ; Density functional theory ; Conjugated system ; Photoluminescence ; Molecular orbital ; Thiophene ; Chromophore ; Chemistry ; Computational chemistry ; Optoelectronics ; Molecule ; Organic chemistry ; Polymer Luminescence and Fluorescent Materials ; Organic Light-Emitting Diodes Research ; Organic Electronics and Photovoltaics
Authors: Alfonso Bayón‐Fernández | Alejandro Méndez‐Ardoy | Carmen Alvarez‐Lorenzo | Juan R. Granja | Javier Montenegro
Source: Journal of Materials Chemistry B (article, 2022-12-02)
Field: Materials Science — Biomaterials

Self-healing cyclic peptide hydrogels Hydrogels are soft materials of great interest in different areas such as chemistry, biology, and therapy. Gels made by the self-assembly of small molecules are known as supramolecular gels. The modulation of their properties by monomer molecular design is still difficult to predict due to the potential impact of subtle structural modifications in the self-assembly process. Herein, we introduce the design principles of a new family of self-assembling cyclic octapeptides of alternating chirality that can be used as scaffolds for the development of self-healing hydrogelator libraries with tunable properties. The strategy was used in the preparation of an amphiphilic cyclic peptide monomer bearing an alkoxyamine connector, which allowed the insertion of different aromatic aldehyde pendants to modulate the hydrophobic/hydrophilic balance and fine-tune the properties of the resulting gel. The resulting amphiphiles were able to form self-healable hydrogels with viscoelastic properties (loss tangent, storage modulus), which were strongly dependent on the nature and number of aromatic moieties anchored to the hydrophilic peptide. Structural studies by SEM, STEM and AFM indicated that the structure of the hydrogels was based on a dense network of peptide nanotubes. Excellent agreement was established between the peptide primary structure, nanotube length distributions and viscoelastic behaviour. Self-healing hydrogels ; Self-healing ; Materials science ; Peptide ; Cyclic peptide ; Self-assembling peptide ; Nanotechnology ; Medicine ; Polymer chemistry ; Chemistry ; Biochemistry ; Pathology Supramolecular Self-Assembly in Materials ; Chemical Synthesis and Analysis ; Glycosylation and Glycoproteins Research
Authors: R. A. Bakar | Yuman Li | Oliver P. Hewitson | Peter J. Roth | Joseph L. Keddie
Source: ACS Applied Materials & Interfaces (article, 2022-06-23)
Field: Chemistry — Organic Chemistry

Azide Photochemistry in Acrylic Copolymers for Ultraviolet Cross-Linkable Pressure-Sensitive Adhesives: Optimization, Debonding-on-Demand, and Chemical Modification Pressure-sensitive adhesives (PSAs) are usually made from viscoelastic, high-molecular-weight copolymers, which are fine-tuned by adjusting the comonomer ratios, molecular weights, and cross-link densities to optimize the adhesion properties for the desired end-use. To create a lightly cross-linked network, an ultraviolet (UV) photoinitiator can be incorporated. Here, we present the first use of perfluorophenylazide chemistry to control precisely a polyacrylate network for application as a PSA. Upon UV irradiation, the highly reactive nitrene from the azide moiety reacts with nearby molecules through a C-H insertion reaction, resulting in cross-linking via covalent bonding. This approach offers three benefits: (1) a means to optimize adhesive properties without the addition of an external photoinitiator; (2) the ability to switch off the tack adhesion on demand via a high cross-linking density; and (3) a platform for additional chemical modification. A series of poly(<i>n</i>-butyl acrylate-<i>co</i>-2,3,4,5,6-pentafluorobenzyl acrylate) or poly(PFBA-<i>co</i>-BA) copolymers were synthesized and modified post-polymerization into the photo-reactive poly(<i>n</i>-butyl acrylate-<i>co</i>-4-azido-2,3,5,6-tetrafluorobenzyl acrylate) [azide-modified poly(PFBA-<i>co</i>-BA)] with various molar contents. When cast into films, the azide-modified copolymers with a high azide content achieved a very high shear resistance after UV irradiation, whereas the tack and peel adhesion decreased strongly with the increase in azide content, indicating that excessive cross-linking occurred. These materials are thus photo-switchable. However, in the low range of azide content, an optimum probe tack adhesion energy was obtained in films with a 0.3 mol % azide content, where a long stress plateau (indicating good fibrillation) with a high plateau stress was observed. An optimum peel adhesion strength was achieved with 0.5 mol % azide. Thus, the adhesion was finely controlled by the degree of cross-linking of the PSA, as determined by the azide content of the copolymer chain. Finally, as a demonstration of the versatility and advantages of the material platform, we show an azide-aldehyde-amine multicomponent modification of the azide copolymer to make a dye-functionalized film that retains its adhesive properties. This first demonstration of using azide functionality has enormous potential for functional PSA design. Materials science ; Copolymer ; Adhesive ; Ultraviolet ; Azide ; On demand ; Pressure sensitive ; Acrylic acid ; Polymer ; Photochemistry ; Polymer chemistry ; Composite material ; Organic chemistry ; Optoelectronics ; Computer science Photopolymerization techniques and applications ; Photochromic and Fluorescence Chemistry ; Luminescence and Fluorescent Materials
Authors: Mahesh G. Hublikar | Vikas D. Kadu | Dattatraya Raut | Sachin P. Shirame | Sivaraj Anbarasu | Muhanna K. Al‐Muhanna | Parameshwar Makam | Raghunath B. Bhosale
Source: Journal of Molecular Structure (article, 2022-03-23)
Field: Chemistry — Organic Chemistry

3-Substituted-2-oxindole derivatives: Design, synthesis and their anti-tuberculosis and radical scavenging dual-action studies Chemistry ; Oxindole ; Radical ; Ascorbic acid ; Combinatorial chemistry ; Scavenging ; Molecule ; Lipinski's rule of five ; Stereochemistry ; Organic chemistry ; Antioxidant ; Biochemistry ; Catalysis Synthesis and biological activity ; Computational Drug Discovery Methods ; Synthesis of heterocyclic compounds
Authors: Emir Al‐Sayed | Annette Rompel
Source: ACS Nanoscience Au (review, 2022-03-02)
Field: Materials Science — Materials Chemistry

Lanthanides Singing the Blues: Their Fascinating Role in the Assembly of Gigantic Molybdenum Blue Wheels Molybdenum blues (MBs) are a distinct class of polyoxometalates, exhibiting versatile/impressive architectures and high structural flexibility. In acidified and reduced aqueous environments, isopolymolybdates generate precisely organizable building blocks, which enable unique nanoscopic molecular systems (MBs) to be constructed and further fine-tuned by hetero elements such as lanthanide (Ln) ions. This Review discusses wheel-shaped MB-based structure types with strong emphasis on the ∼30 Ln-containing MBs as of August 2021, which include both organically hybridized and nonhybridized structures synthesized to date. The spotlight is thereby put on the lanthanide ions and ligand types, which are crucial for the resulting Ln-patterns and alterations in the gigantic structures. Several critical steps and reaction conditions in their synthesis are highlighted, as well as appropriate methods to investigate them both in solid state and in solution. The final section addresses the homogeneous/heterogeneous catalytic, molecular recognition and separation properties of wheel-shaped Ln-MBs, emphasizing their inimitable behavior and encouraging their application in these areas. Lanthanide ; Molybdenum ; Blues ; Aqueous solution ; Homogeneous ; Materials science ; Ligand (biochemistry) ; Nanoscopic scale ; Nanotechnology ; Solid-state ; Catalysis ; Flexibility (engineering) ; Ion ; Computer science ; Chemistry ; Inorganic chemistry ; Physical chemistry ; Physics ; Organic chemistry ; Mathematics Polyoxometalates: Synthesis and Applications ; Metal-Organic Frameworks: Synthesis and Applications ; Lanthanide and Transition Metal Complexes
Authors: Koushik Saha | Sundargopal Ghosh
Source: Dalton Transactions (review, 2022-01-01)
Field: Chemistry — Organic Chemistry

Hydroboration reactions using transition metal borane and borate complexes: an overview In recent years, the chemistry of transition metal borane and borate complexes has advanced fast with reasonable growth. Frequent utilisation of these complexes in hydrofunctionalisation reactions is one of the key driving forces for their development. As a result, the important role of borate complexes in the hydroboration/hydrosilylation/hydroamination of unsaturated organic species has been successfully demonstrated together with the isolation of many different boron-containing transition metal complexes such as borataallyl, vinylborane, silyl complexes featuring the known bonding modes of boron. Both the uncatalysed and catalysed hydroboration reactions using the transition metal borane/borate complexes are known, which show these complexes' huge potential. Careful investigation and fine-tuning of the electronic and steric properties of the borane/borate ligands has facilitated the synthesis of these transition metal complexes which are convenient for use in the hydroboration reactions. Furthermore, the systematic development of this field has established the connection between the structure and reactivity of these complexes and their utilisation in hydroboration reactions. This Frontier sheds light on the recent developments that have been made with hydroboration reactions using transition metal borane/borate complexes. Also, in this Frontier we have provided meaningful synthetic methods to make new boron-containing transition metal complexes together with mechanistic insights for some of these reactions. Hydroboration ; Borane ; Boron ; Chemistry ; Transition metal ; Boranes ; Organic chemistry ; Catalysis Organoboron and organosilicon chemistry ; Asymmetric Hydrogenation and Catalysis ; Organometallic Complex Synthesis and Catalysis
Authors: G. Murali | Thangaian Kesavan | G. Anandha Babu | S. Ponnusamy | S. Harish | M. Navaneethan
Source: Journal of Alloys and Compounds (article, 2022-02-25)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Improved supercapacitor performance based on sustainable synthesis using chemically activated porous carbon Supercapacitor ; Activated carbon ; Porosity ; Materials science ; Chemical engineering ; Nanotechnology ; Chemistry ; Electrochemistry ; Electrode ; Composite material ; Organic chemistry ; Adsorption ; Engineering Supercapacitor Materials and Fabrication ; Advanced battery technologies research ; Advancements in Battery Materials
Authors: Yue Chen | Zheng Xue | Yue He | Yue Han | Jilin Zhang | Zhongxian Qiu | Wenli Zhou | Liping Yu | Shixun Lian
Source: Materials Research Bulletin (article, 2022-01-20)
Field: Materials Science — Materials Chemistry

Precisely control the ultraviolet to blue light conversion for plant growth: Rigid crystal structure, lattice substitution and flux effect in the Ca1.1Sr0.9SiO4:Ce3+, Li+ phosphor Luminescence ; Phosphor ; Photoluminescence ; Rietveld refinement ; Crystal structure ; Materials science ; Doping ; Crystallography ; Analytical Chemistry (journal) ; Optoelectronics ; Chemistry Luminescence Properties of Advanced Materials ; Ammonia Synthesis and Nitrogen Reduction ; bioluminescence and chemiluminescence research
Authors: Alexandre C. Foucher | Meikang Han | Christopher E. Shuck | Kathleen Maleski | Yury Gogotsi | Eric A. Stach
Source: 2D Materials (article, 2022-01-14)
Field: Materials Science — Materials Chemistry

Shifts in valence states in bimetallic MXenes revealed by electron energy-loss spectroscopy (EELS) Abstract MXenes are an emergent class of two-dimensional materials with a very wide spectrum of promising applications. The synthesis of multiple MXenes, specifically solid-solution MXenes, allows fine tuning of their properties, expands their range of applications, and leads to enhanced performance. The functionality of solid-solution MXenes is closely related to the valence state of their constituents: transition metals, oxygen, carbon, and nitrogen. However, the impact of changes in the oxidation state of elements in MXenes is not well understood. In this work, three interrelated solid-solution MXene systems (Ti 2− y Nb y CT x , Nb 2− y V y CT x , and Ti 2− y V y CT x ) were investigated with scanning transmission electron microscopy and electron energy-loss spectroscopy to determine the localized valence states of metals at the nanoscale. The analysis demonstrates changes in the electronic configuration of V upon modification of the overall composition and within individual MXene flakes. These shifts of oxidation state can explain the nonlinear optical and electronic features of solid-solution MXenes. Vanadium appears to be particularly sensitive to modification of the valence state, while titanium maintains the same oxidation state in Ti–Nb and Ti–V MXenes, regardless of stoichiometry. The study also explains Nb’s influential role in the previously observed electronic properties in the Nb–V and Nb–Ti systems. MXenes ; Valence (chemistry) ; Materials science ; Electron energy loss spectroscopy ; X-ray photoelectron spectroscopy ; Titanium carbide ; Vanadium ; Solid solution ; Chemical physics ; Chemistry ; Titanium ; Nanotechnology ; Transmission electron microscopy ; Chemical engineering MXene and MAX Phase Materials ; 2D Materials and Applications ; Advanced Memory and Neural Computing