Article
Polymer Science
Ugochukwu Okoli, Kabir Rishi, Gregory Beaucage, Hendrik K. Kammler, Alex McGlasson, Michael Chauby, Vishak Narayanan, James Grammens, Vikram K. Kuppa
Summary: In polymer nanocomposites, surface modification of silica aggregates can hinder Coulombic interactions, allowing for better dispersion and network formation. Surface modification is typically done using silane coupling agents, but carbon-coating during silica production is also an option. This study explores the impact of flame synthesized silica with different surface carbon contents on dispersion, structure, and rheological response in rubber nanocomposites. The presence of silanol groups on the surface of pristine silica leads to poor network formation, while carbon monolayers on flame synthesized silica can mitigate charge repulsion and affect structural emergence. The rheological response depends on the surface density of both carbon and silanol groups.
Article
Materials Science, Composites
Tingting Zhang, Xuhui Chen, Zhenyou Guo, Youbo Zhao, Hao Xiu, Hongwei Bai, Qin Zhang, Qiang Fu
Summary: This study demonstrates a novel route to control the distribution of hydrophilic silica in polymer blends by tailoring the silanol number of the silica, resulting in improved impact toughness and maintained strength and modulus of the blends.
COMPOSITES COMMUNICATIONS
(2021)
Article
Chemistry, Applied
J. N. Diaz de Leon, A. L. Castaneda-Garcia, C. E. Soto-Arteaga, G. Torres-Otanez, Y. Esqueda-Barron, M. A. Guzman-Cruz, G. Alonso-Nunez, S. Fuentes-Moyado
Summary: Experimental analysis showed that Al2O3-TiO2 binary mixed oxides can be used as supports of NiW hydrodesulfurization catalysts. The use of different surfactants led to significant differences in pore-size distribution, surface composition, and morphology. Additionally, XPS analysis confirmed the surface enrichment with alumina, impacting the activity of the NiW catalysts.
Article
Materials Science, Ceramics
A. R. Ghiasi, A. Yaghtin, N. Hosseinabadi, L. Ghalandari
Summary: This study investigates the impact of suspension parameters on its stability and optimizes the suspension for plasma spraying. The optimized suspension with desired viscosity, zeta potential, and turbidity is used as feedstock for coating, resulting in a columnar coating morphology with satisfactory porosity for high-temperature applications.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Physical
F. J. Rubio-Hernandez, E. Fernandez-Diaz, J. F. Velazquez-Navarro
Summary: This study investigates the influence of temperature and solid concentration on the stress-induced shear-thickening behavior of A200PPG400 suspension, and proposes a more detailed description of the shear-thickening mechanism based on the analysis of intrinsic viscosity and activation energy for the viscous flow.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Chemistry, Multidisciplinary
Carla Calabrese, Valeria La Parola, Simone Cappello, Annamaria Visco, Cristina Scolaro, Leonarda Francesca Liotta
Summary: Silica, titania, and mixed silica-titania powders were used as supports for loading copper and silver, resulting in nanomaterials with antifouling properties. The titania-based coatings showed better adhesion than silica-based coatings and the commercial topcoat.
Article
Chemistry, Physical
Pengfei Liu, Mingyong Du, Yee-Kwong Leong, Peta Clode, Jishan Liu
Summary: The composite LAPONITE (R)-spherical metal oxides (L-SMO) gels have a stronger microstructure and higher yield stress compared to pure LAPONITE (R) gels. Additionally, the microstructure of composite L-SMO gels changes with ageing time, showing time-dependent behavior.
APPLIED CLAY SCIENCE
(2021)
Article
Polymer Science
Hao Zhang, Wei Yu, Fenggang Bian, Wei You
Summary: This work illustrates the influence of particle-polymer interaction on the uniformity of particle dispersion and mechanical enhancement. Different interfacial adhesion energies result in different uniformities of particle dispersion, while the preshear stress only affects the critical concentration. The power-law exponents in nanocomposites with lower interfacial adhesion energy show significant deviations from the theoretical prediction in homogeneous dispersion systems.
Article
Physics, Multidisciplinary
Philippe Bourrianne, Vincent Niggel, Gatien Polly, Thibaut Divoux, Gareth H. McKinley
Summary: Shear thickening refers to the reversible increase in viscosity of a suspension of rigid particles under external shear. The microscopic origin of shear thickening has been attributed to hydrodynamic interactions and frictional contact between particles, but their relative contribution is still debated. In this study, a model shear-thickening suspension was used to independently tune the surface chemistry and surface roughness of particles, showing that both properties are important for continuous and discontinuous shear thickening. The presence of hydrogen bonds between particles is essential for achieving the latter. The onset of continuous shear thickening was predicted using a simple argument, and it was found to occur at a lower critical volume fraction compared to previous literature. Furthermore, mixtures of particles with opposing surface chemistry were demonstrated to finely tune the shear-thickening response of the suspension at a fixed volume fraction.
PHYSICAL REVIEW RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Siyi Xu, Cheng Zhou, Jianxi Li, Liguo Shen, Hongjun Lin
Summary: By adjusting the fraction of fumed silica, a series of flame-retardant ethylene vinyl acetate (EVA) composites with excellent properties were prepared, showing high hydrophobicity, excellent mechanical properties, and good flame-retardant effects.
MATERIALS TODAY COMMUNICATIONS
(2021)
Article
Polymer Science
Ting-Ting Zhang, Mei-Xi Zhou, Zhen-You Guo, You-Bo Zhao, Di Han, Hao Xiu, Hong-Wei Bai, Qin Zhang, Qiang Fu
Summary: This study investigates the control of selective distribution of silica nanoparticles with different specific surface areas in elastomer-toughened plastic blends. It was found that silica nanoparticles with low specific surface area tend to be located at the interface between the matrix and dispersed phase, leading to improved impact toughness while maintaining strength and modulus. The toughening efficiency also increases with the specific surface area of silica nanoparticles when interfacial distribution is the same.
CHINESE JOURNAL OF POLYMER SCIENCE
(2021)
Article
Metallurgy & Metallurgical Engineering
Setare Dodange, Reza Riahifar, Babak Raissi, Maziar S. Yaghmaee, Amir Alhaji
Summary: This study investigates heterocoagulation in alumina-silica suspension using 2-dimensional discrete element method simulations. The size and size ratio of particles play important roles in determining the degree of heterocoagulation and the structure of the suspension. The results demonstrate that suspension composition can be used to tune the heterocoagulation structure.
INTERNATIONAL JOURNAL OF MATERIALS RESEARCH
(2022)
Article
Chemistry, Physical
Zeynep Ayla, Darshan Patel, Arzam Harris, David W. Flaherty
Summary: This study found that atomically dispersed Ti sites on metal oxides can activate H2O2 to create intermediates active for alkene epoxidation reactions. By comparing reaction rates, electronic properties, and non-covalent interactions on different metal oxide catalysts, the researchers discovered a correlation between water adsorption at the solid-liquid interface and the stability of epoxidation transition states.
JOURNAL OF CATALYSIS
(2022)
Article
Energy & Fuels
Marcel J. Herzog, Nicolas Gauquelin, Daniel Esken, Johan Verbeeck, Juergen Janek
Summary: The dry powder coating process with nanostructured fumed metal oxides for high-Ni cathode active materials can significantly improve the capacity retention, cycle life, and rate performance, reducing the formation of solid electrolyte interface (SEI) and charge transfer impedance during cycling. The stable coating layer formed during cycling also enhances lithium ion diffusivity and performance.
Article
Chemistry, Physical
Shinya Matsuura, Tadanori Hashimoto, Atsushi Ishihara
Summary: Novel alumina and titania modified by silica were prepared using the GSR method, resulting in the observation of new acid sites. The mixed catalysts showed higher conversion and improved gasoline fraction selectivity compared to single-component catalysts.
APPLIED CATALYSIS A-GENERAL
(2021)
Article
Polymer Science
Iryna Protsak, Volodymyr Gun'ko, Yevhenii Morozov, Ian M. Henderson, Dong Zhang, Zhang Yinjun, Volodymyr Turov
Summary: This study investigated the cleavage of siloxane bonds in polydimethylsiloxane using a mixture of dimethyl carbonate and tris(pentafluorophenyl)borane, finding that the cleavage can be achieved under mild conditions. The addition of tris(pentafluorophenyl)borane enhanced the depolymerization process, showing potential for silicone recycling and production of new OS polymers. Computational calculations revealed the mechanism behind the cleavage reaction, suggesting stable complexes formation between DMC molecules and B(C6F5)(3).
Article
Nanoscience & Nanotechnology
Alla G. Dyachenko, Olena V. Ischenko, Olena V. Goncharuk, Mykola V. Borysenko, Olexandr V. Mischanchuk, Volodymyr M. Gun'ko, Dariusz Sternik, Vladyslav V. Lisnyak
Summary: Four different catalysts were prepared for CO2 methanation, with Ni(5)Co(5)/SiO2 and Ni(2)Co(8)/SiO2 showing excellent catalytic activity and high methane yield. The methanation reaction was found to pass through the formation of O-containing intermediates bound to the active Ni-Co and nanosilica sites, as revealed by thermo-programmed desorption mass spectroscopy.
APPLIED NANOSCIENCE
(2022)
Article
Chemistry, Physical
Vladimir V. Turov, Vladimir M. Gun'ko, Tetyana Krupska, Mykola Borysenko, Magdalina D. Tsapko, Nataliia Guzenko, Mykola T. Kartel
Summary: This study investigates the improved methane adsorption conditions provided by the nanoparticle/aggregate/agglomerate structure, texture, and surface characteristics of hydrophobic nanosilica AM1 treated with arginine and water. Characterization methods such as adsorption, desorption, microscopy, spectroscopy, XRD, SAXS, and quantum chemistry were used. The presence of bound water in wetted composites enhances nanoporosity and facilitates methane adsorption up to 7.3-4.9 wt% at 199-283 K.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2021)
Article
Chemistry, Multidisciplinary
Mariia Galaburda, Viktor Bogatyrov, Dariusz Sternik, Olena Oranska, Mykola Borysenko, Ivan Skorvanek, Ewa Skware, Anna Derylo-Marczewska, Volodymyr Gun'ko
Summary: The study investigated the conversion of metal-modified sawdust into magneto-sensitive porous composites using thermal carbonization, finding that the structural and morphological characteristics of the materials strongly depend on the metal precursor's types. The metal-carbon nanocomposites exhibited soft magnetic properties and efficient sorption capabilities for contaminants in aqueous solutions.
CHEMISTRY JOURNAL OF MOLDOVA
(2021)
Article
Chemistry, Physical
V. M. Gun'ko
Summary: The particulate morphology and texture of silicas, carbons, and porous polymers were analyzed using adsorption, SAXS, and microscopic methods. Different correlations between pore volume and specific surface area were observed for different material classes. The nanopores in activated carbons transformed into narrow mesopores with changes in activation time.
APPLIED SURFACE SCIENCE
(2021)
Article
Biochemistry & Molecular Biology
Iryna S. Protsak, Yevhenii M. Morozov, Dong Zhang, Volodymyr M. Gun'ko
Summary: The study investigated the molecular interactions between a silica surface and organic/inorganic polymers using solid-state NMR spectroscopy, revealing that the pretreatment temperature of silica nanoparticles affects the grafting of modifier blends onto the surface. Different surface areas and size distributions of silica nanoparticles also impact the textural characteristics of the modified surfaces.
Article
Chemistry, Physical
Volodymyr V. Turov, Tetyana V. Krupska, Nataliia V. Guzenko, Mykola V. Borysenko, Yury M. Nychiporuk, Volodymyr M. Gun'ko
Summary: This study investigates the influence of hierarchical nanoparticle/aggregate/agglomerate structure, texture, and surface characteristics of hydrophobic nanosilica AM1 stirred with a small amount of water on the behaviors of weakly and strongly associated waters. The results show significant reorganization of the interfacial water forming clusters and domains differently affected by various co-adsorbates. The findings provide insights into the quantitative analysis of weakly and strongly associated waters affected by different co-adsorbates.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Environmental Sciences
Mariia Galaburda, Alicja Bosacka, Dariusz Sternik, Viktor Bogatyrov, Olena Oranska, Volodymyr Gun'ko, Anna Derylo-Marczewska
Summary: In this study, novel hybrid carbon-mineral materials were synthesized and their adsorption efficiency in wastewater treatment was investigated. The results showed that the materials exhibited good adsorption performance and differentiated selectivity towards different organic compounds. These findings demonstrate the potential of biochars as materials for water and wastewater remediation.
Article
Chemistry, Physical
V. M. Gun'ko
Summary: Complex fumed nanooxides SiO2/Al2O3, SiO2/TiO2, and Al2O3 /SiO2/TiO2 were studied and found that the interior and surface contents of alumina in SA and AST are nonmonotonic functions of total Al2O3 content, while the titania in ST and AST is not affected. This is due to the difference in precursor reactivity of Al2Cl6 and SiCl4 vapor compared to TiCl4 and SiCl4 vapor. Additionally, titania tends to form cores while silica forms NPNP shells.
Article
Environmental Sciences
Mariia Galaburda, Alicja Bosacka, Dariusz Sternik, Olena Oranska, Mykola Borysenko, Volodymyr Gun'ko, Anna Derylo-Marczewska
Summary: Magnetosensitive biochars were prepared by mechanochemical ball-milling of lignin and blast furnace dust, followed by pyrolysis. The materials were characterized using various techniques, and the adsorption studies showed their potential in water remediation.
Article
Chemistry, Physical
Yu. V. Yavorskyi, A. B. Hrubiak, Ya. V. Zaulychnyy, M. V. Karpets, V. V. Moklyak, V. M. Gun'ko, O. I. Dudka
Summary: This study investigates the relationship between the electrochemical properties and grinding duration of mixed nanosilica and nanoalumina powders. It explores the impact of structural and morphological changes on the electrochemical characteristics of the nanocomposite powder. The study utilizes techniques such as scanning electron spectroscopy, X-ray diffraction analysis, and ultra-soft X-ray emission spectroscopy to analyze the structural and morphological characteristics.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Physical
Volodymyr M. Gun'ko, Volodymyr V. Turov, Tetyana Krupska, Mykola Borysenko
Summary: This study investigates the temperature and interfacial behaviors of concentrated alkali solutions under confined space effects. The findings illustrate that the characteristics of bound water and water/NaOH clusters strongly depend on the hydrophilicity/hydrophobicity of nanosilicas, dispersion media, and the deposition sequence of NaOH and water.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Biochemistry & Molecular Biology
Victoria Paientko, Olena I. Oranska, Volodymyr M. Gun'ko, Ewa Skwarek
Summary: To improve the properties of rose clay composites, mechanical treatment was used to prepare nanostructured composites with natural and synthetic nanomaterials. Various characterization methods were employed to analyze the materials. The composites showed enhanced release of bioactive substances and demonstrated potential for cosmetic applications.
Article
Chemistry, Multidisciplinary
Mirtemir Kurbanov, Lyudmyla Andriyko, Jamshid Panjiev, Sardor Tulaganov, Volodymyr Gun'ko, Andrii Marynin, Stanislaw Pikus
Summary: A new pilot plant equipment has been developed that utilizes the physical effects of sublimation and desublimation for processing silicon-containing raw materials. By using this equipment, amorphous silicon dioxide and iron oxide can be separated from metallurgical waste, resulting in a collective concentrate of valuable components.
JOURNAL OF NANOPARTICLE RESEARCH
(2023)
Article
Nanoscience & Nanotechnology
T. Krupskaya, V. M. Gun'ko, L. S. Andriyko, N. Yelahina, V. V. Turov
Summary: The study showed that in hydrated powders, water fills the interparticle voids of nanosilica in the form of submicron clusters, with interfacial energy directly proportional to added water. At high water concentrations, water structures spontaneously increase in size, accompanied by a sharp decrease in interfacial energy. Aqueous suspensions of AM-1 easily mix with chloroform, forming stable suspensions, and methyl silica suspensions exhibit high thixotropic properties depending on applied mechanical loads.
PHYSICS AND CHEMISTRY OF SOLID STATE
(2021)