Ti3C2Tx MXene is one of the most comprehensively studied 2D materials in terms of its adsorptive, transport, and catalytic properties, cytotoxic performance, etc. Still, conventional MXene synthesis approaches provide low single-flake MXene yield and frequently uncontrollable properties, demanding further post-processing. The MXene family also lacks magnetism, which is helpful for producing effective nanoadsorbents as their magnetic decantation is the cheapest and most convenient way to remove the spent adsorbent from water. Composite materials consisting of magnetic nanoparticles grown on top of MXene flakes are commonly used to provide magnetic properties to the resulting nanocomposite. In this paper, we study the possibility to delaminate multilayer Ti3C2Tx MXene sheets directly by growing iron oxide magnetic nanoparticles inside their interlayer spacing. We find out that, with a mass fraction of particles comparable or exceeding that of MXenes, their growth is accompanied by an effective enhancement of single-layer MXene yield and suitable magnetic properties of the resulting composite. The developed approach can be further used for simplifying synthesis protocols to obtain magnetic MXene-based nanoadsorbents with tunable properties.
1 June 2023 in Bulletin of the Russian Academy of Sciences: Physics
It is shown that surface-modified magnetic iron oxide nanoparticles with an average size of about 10 nm have a high adsorption capacity for the sorption of
Higher lipophilicity facilitates the passage of a substance across lipid cell membranes, the blood–brain barrier and protein binding, and may also indicate its toxicity. We proposed eight methods for predicting the lipophilicity of the 22 most commonly used organophosphate pesticides. In this work, to determine the lipophilicity and thermodynamic parameters of the solvation of pesticides, we used methods of density functional theory with various basis sets, as well as modern Grimm methods. The prediction models were evaluated and compared against eight performance statistics, as well as time and RAM used in the calculation. The results show that the PBE-SVP method provided the best of the proposed predictive capabilities. In addition, this method consumes relatively less CPU and RAM resources. These methods make it possible to reliably predict the ability of pesticide molecules to penetrate cell membranes and have a negative effect on cells and the organism as a whole.
5 November 2016 in Journal of Analytical Chemistry
In the context of the extensive application prospect of two-dimensional (2D) chalcogenides, we synthesized layered SnSe2+δ bulks with defects employing a hybrid chemical vapor transport-melt approach. Both the Eg and A1g Raman characteristic peaks in SnSe2+δ are dominated by cubic anharmonicity, coupled with nonlinear temperature dependencies below 140 K. Notably, the reduction in phonon energy observed in these vibrational modes can be ascribed to defect-mediated Raman scattering, irrespective of deficient or excess Se defects. However, the lower consistency in the Raman shifts of the in-plane Eg vibrations compared to the out-of-plane A1g modes suggests that the defects predominantly entail the absence of Se atoms and the substitutions of Sn by Se, delineating a continuum of Se-deficient and Se-enriched compositions. Furthermore, Se defects induce the contraction of the indirect bandgaps, facilitating a transition from medium to narrow bandgap semiconductors in SnSe2+δ, which underscores the tunable nature of the bandgaps through the incorporation of Se defects. These discoveries present an avenue for bandgap engineering and foster a deeper comprehension of the phonon and thermal properties of layered chalcogenides for further advanced technologies.
This study investigates the sorption of 2-methyl orange dye onto octadecylamine-modified iron oxide magnetic nanoparticles (ODA-IONPs). The synthesized ODA-IONPs exhibit remarkable sorption capacity, reaching 800 mg/g at the nanoparticle concentrations ranging from 5 to 10 mg/g and pH of 2–8. The sorption process demonstrates rapid kinetics, achieving 90% of maximum sorption within 0.5 min. Thermodynamic analysis showed that sorption process is spontaneous and endothermic, as indicated by negative ΔG and positive ΔH values. The pseudo-second-order and Langmuir models best describe the sorption kinetics at 293 K (R² 0.99). Compared to other adsorbents, ODA-IONPs show superior MO removal capacity under a wider pH range. The influence of nanoparticle concentration, pH, and temperature on sorption efficiency is systematically explored, with optimal conditions identified at 10 mg/L ODA-IONPs and pH 6. Furthermore, the feasibility of nanoparticle reusability for sorption purposes is assessed. These findings underscore the potential of ODA-IONPs as efficient sorbents for wastewater treatment and environmental remediation applications.