The surface charge densities and surface potentials of selected phyllosilicate surfaces were calculated from AFM surface force measurements and reported as a function of ionic strength at pH 5.6. The results show that the silica faces of clay minerals follow the constant surface charge model because of isomorphous substitution in the silica tetrahedral layer. A decreasing surface charge density sequence was observed as follows: muscovite silica face>kaolinite silica face>talc silica face, which is expected to be due to the extent of isomorphous substitution. In contrast, at pH 5.6, the alumina face and the edge surface of kaolinite follow the constant surface potential model with increasing ionic strength, and the surface charge density increased with increasing ionic strength. The cluster size of suspended kaolinite particles at pH 5.6 was found to increase with increasing ionic strength due to an increase in the surface charge density for the alumina face and the edge surface. However, the cluster size decreased at 100mM KCl as a result of an unexpected decrease in the surface charge of the alumina face. When the ionic strength continued to increase above 100mM KCl, the van der Waals attraction dominated and larger clusters of micron size were stabilized.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.jcis.2014.06.028 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Molecular Design of Hole-Collecting Materials for Co-Deposition Processed Perovskite Solar Cells: A Tripodal Triazatruxene Derivative with Carboxylic Acid Groups.
J Am Chem Soc
January 2025
Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.
High-performance and cost-effective hole-collecting materials (HCMs) are indispensable for commercially viable perovskite solar cells (PSCs). Here, we report an anchorable HCM composed of a triazatruxene core connected with three alkyl carboxylic acid groups (). In contrast to the phosphonic acid-containing tripodal analog (), molecules can form a hydrophilic monolayer on a transparent conducting oxide surface, which is beneficial for subsequent perovskite film deposition in the traditional layer-by-layer fabrication process.
View Article and Find Full Text PDFMechanistic Understanding of the pH-Dependent Oxygen Reduction Reaction on the Fe-N-C Surface: Linking Surface Charge to Adsorbed Oxygen-Containing Species.
ACS Appl Mater Interfaces
January 2025
Center of Nanomaterials for Renewable Energy (CNRE), State Key Laboratory of Electrical Insulation and Power Equipment, School of Electrical Engineering, Xi'an Jiaotong University, Xi'an 710049, P. R. China.
The Fe-N-C catalyst, featuring a single-atom Fe-N configuration, is regarded as one of the most promising catalytic materials for the oxygen reduction reaction (ORR). However, the significant activity difference under acidic and alkaline conditions of Fe-N-C remains a long-standing puzzle. In this work, using extensive ab initio molecular dynamics (AIMD) simulations, we revealed that pH conditions influence ORR activity by tuning the surface charge density of the Fe-N-C surface, rather than through the direct involvement of HO or OH ions.
View Article and Find Full Text PDFDigital Profiling of Tumor Extracellular Vesicle-Associated RNAs Directly from Unprocessed Blood Plasma.
ACS Nano
January 2025
Department of Biomedical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, South Korea.
Tumor-derived extracellular vesicle (tEV)-associated RNAs hold promise as diagnostic biomarkers, but their clinical use is hindered by the rarity of tEVs among nontumor EVs. Here, we present EV-CLIP, a highly sensitive droplet-based digital method for profiling EV RNA. EV-CLIP utilizes the fusion of EVs with charged liposomes (CLIPs) in a microfluidic chip.
View Article and Find Full Text PDFHow amino acids intercalate in CaFe layered double hydroxides: A combined RIXS and NEXAFS study.
Chemphyschem
January 2025
Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, PS-ISRR, GERMANY.
Two-dimensional layered double hydroxides (LDHs) are ideal candidates for a large number of (bio)catalytic applications due to their flexible composition and easy to tailor properties. Functionality can be achieved by intercalation of amino acids (as the basic units of peptides and proteins). To gain insight on the functionality, we apply resonant inelastic soft x-ray scattering and near edge x-ray absorption fine structure spectroscopy to CaFe LDH in its pristine form as well as intercalated with the amino acids proline and cysteine to probe the electronic structure and its changes upon intercalation.
View Article and Find Full Text PDFPreparation of Zwitterionic Sulfobetaines and Study of Their Thermal Properties and Nanostructured Self-Assembling Features.
Nanomaterials (Basel)
January 2025
Renewable Energy Laboratory, National Laboratory Astana, Nazarbayev University, Astana 010000, Kazakhstan.
Zwitterionic polymers have garnered significant attention for their distinctive properties, such as biocompatibility, antifouling capabilities, and resistance to protein adsorption, making them promising candidates for a wide range of applications, including drug delivery, oil production inhibitors, and water purification membranes. This study reports the synthesis and characterization of zwitterionic monomers and polymers through the modification of linear, vinyl, and aromatic heterocyclic functional groups via reaction with 1,3-propanesultone. Four zwitterionic polymers with varying molecular structures-ranging from linear to five and six membered ring systems-were synthesized: poly(sulfobetaine methacrylamide) (pSBMAm), poly(sulfobetaine-1-vinylimidazole) (pSB1VI), poly(sulfobetaine-2-vinylpyridine) (pSB2VP), and poly(sulfobetaine-4-vinylpyridine) (pSB4VP).
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!