Two simple and straightforward procedures for determining the organic content of hybrid silica materials by means of conventional NMR and GC/MS techniques are described. The methods involve dissolving the hybrid material either in a concentrated solution of sodium hydroxide in deuterated water containing a suitable reference or in a solution of hydrogen fluoride in water and extracting with methylene chloride. These methods constitute useful routine techniques for obtaining immediate information concerning both the amount and chemical composition of the organic compounds on the silica surface.
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http://dx.doi.org/10.1021/ac801248m | DOI Listing |
Langmuir
January 2025
Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, United States.
Modification of silica interfaces by covalent attachment of functional ligands is a primary means of controlling the interfacial chemistry of porous silicas used in separations, environmental cleanup, and biosensing. Recently, modification of hydrophobic, -alkyl-silane-functionalized interfaces has been achieved through self-assembly of zwitterionic phospholipids or mixed-charged surfactants to form "hybrid bilayers", producing interfaces that mimic lipid-bilayer partitioning and provide shape-selective partitioning of aromatic hydrocarbons. Charged headgroups, however, introduce electrostatic interactions that strongly influence the retention of ionizable solutes and require careful control over pH and ionic strength in the solution phase.
View Article and Find Full Text PDFAdv Colloid Interface Sci
January 2025
Pharmaceutical Sciences Laboratory, Faculty of Science and Engineering, Åbo Akademi University, Biocity (3rd fl.), Tykistökatu 6A, 20520 Turku, Finland; Turku Bioscience Centre, University of Turku and Åbo Akademi University, Biocity (5th fl.), Tykistökatu 6A, 20520 Turku, Finland. Electronic address:
In the realm of hybrid nanomaterials, the construction of core/shell nanoparticles offer an effective strategy for encompassing a particle by a polymeric or other suitable material, leading to a nanocomposite with distinct features within its structure. The polymer shell can be formed via nanoprecipitation, optimized by manipulating fluid flow, fluid mixing, modulating device features in microfluidics. In addition to the process optimization, success of polymer assembly in encapsulation strongly lies upon the favorable molecular interactions originating from the diverse chemical environment shared between core and shell materials facilitating formation of core/shell nanostructure.
View Article and Find Full Text PDFNano Lett
January 2025
Facultad de Ciencias Exactas y Naturales, Departamento de Física, Universidad de Buenos Aires, 1428 Buenos Aires, Argentina.
Nanostructured high-index dielectrics have shown great promise as low-loss photonic platforms for wavefront control and enhancing optical nonlinearities. However, their potential as optomechanical resonators has remained unexplored. In this work, we investigate the generation and detection of coherent acoustic phonons in individual crystalline gallium phosphide nanodisks on silica in a pump-probe configuration.
View Article and Find Full Text PDFJ Phys Chem A
January 2025
Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States.
When dielectrics are hit with intense infrared (IR) laser pulses, transient metalization can occur. The initial attosecond dynamics behind this metallization are not entirely understood. Therefore, simulations are needed to understand this process and to help interpret experimental observations of it, such as with attosecond transient absorption (ATA).
View Article and Find Full Text PDFSoft Matter
January 2025
Faculty of Science and Letters, Department of Chemistry, Soft Materials Research Laboratory, Istanbul Technical University, Istanbul, Maslak, 34469, Turkey.
A series of anionic poly(acrylamide--sodium acrylate)/poly(ethylene glycol), PAN/PEG, hybrids were conveniently synthesized free radical aqueous polymerization by integrating bentonite, kaolin, mica, graphene and silica, following a simple and eco-friendly crosslinking methodology. A comparative perspective was presented on how integrated nanofillers affect the physicochemical properties of hybrid gels depending on the differences in their structures. Among the five types of nanofillers, bentonite-integrated hybrid gel had the highest water absorbency, while graphene-integrated gel had the lowest.
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