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Developing sustainable strategies for immobilizing heavy metal contaminants in subsurface environments is critical for advancing environmental remediation technologies. Elucidating the interactive mechanisms between Cu²⁺, clays, and polymers is crucial for the development of advanced barrier materials for copper contamination. In this research molecular dynamics (MD) was employed to simulate the swelling behavior of carboxymethyl cellulose (CMC)-modified hexagonal montmorillonite (MMT) under CuCl₂ concentrations ranging from 0 to 100 mM. Addition of CMC was shown to expand the interlamellar distance from 17.6 (unmodified MMT) to 67.02 Å (100 mM) in general. Analysis of density distributions, RDF, adsorption isotherms, and adsorption kinetics suggested a dual role of CuCl₂ in MMT swelling. At CuCl₂ concentrations of 20–60 mM, CMC facilitated intercalation and cation bridging, resulting in a maximum interlamellar distance of 79.51 Å at 20 mM. Beyond 60 mM, swelling was reduced due to charge screening, with interlamellar distance decreasing to 54.52 Å at 100 mM. Notably, the MMT edge surface exhibited selective adsorption of Na⁺ over Cu²⁺ due to the lower charge, smaller hydrodynamic radius and partial formation of inner-sphere complexes of Na⁺, preserving edge-specific interactions even at high Cu²⁺ concentrations. Comparison with DLVO theory highlighted the much lower concentrated ion distribution near basal surfaces calculated from MD, attributed to the assumptions of the continuum model not taking ion size into account. These findings provided a quantitative understanding of the interactions between CMC, MMT, and Cu²⁺ ions, offering insights into optimizing polymer-clay composites for environmental remediation.

Developing monovalent anion-selective membranes (MAPMs) faces challenges, including the trade-off between flux and selectivity, membrane stability, and cost-effective fabrication. Overcoming these requires advanced material design and scalable techniques. Here, we introduce in situ interfacial polymerization (ISIP) to prepare MAPMs. Base membranes are synthesized via superacid polymerization and modified with anion channels and -NH2 groups. During ISIP, trimesoyl chloride reacts with surface -NH2 groups, forming a partially crosslinked structure with -COOH groups to regulate ion transport via electrostatic interactions. This results in low membrane resistance (4.7 Ω cm2) and selective transport of weakly hydrated ions (Cl−, Br−, NO3−), while strongly hydrated ions (SO42−, F−) face higher barriers. MAPMs demonstrate high performance, achieving a limiting current density (>90 mA cm−2), Cl− flux (1.98 mol m−2 h−1 at 5 mA cm−2), and selectivity (244 for Cl−/SO42−), confirming effective hydration dynamics control and balanced performance. Simulations reveal how charge distribution affects ion migration pathways.

A biobased anode material for sodium-ion batteries (SIBs) was prepared through the simple pyrolysis of Scotch pine cones (Pinus sylvestris, SPC), followed by a heteroatom doping modification. The resulting nitrogen-doped hard carbon exhibited a high reversible capacity of 273 mA·h·g-1 at a current density of 25 mA·g-1 compared to the undoped material (197 mA·h·g-1). X-ray diffraction analysis shows that the produced hard carbon from the biomass is highly amorphous in nature, and high-resolution transmission electron microscopy images reveal the presence of localized graphite-like structures that are found to be beneficial for the storage and transport of Na+ ions during charging/discharging. Experimental results demonstrated that the increased specific surface area (SBET = 424 m2·g-1), high micropore volume (0.177 cm3·g-1), and expanded interlayer spacing (>3.7 Å) and a high Na+-ion diffusion coefficient (3.08 × 10-16 cm2·s-1) facilitated the diffusion of sodium ions, leading to a high capacity retention of 80% after 250 cycles for the SPC-N material over the undoped one, SPC (71%). This study highlights the potential of low-cost, widely available biobased Scotch pine cones as an alternative anode material to enhance the sustainability of SIB production.

Liquid water is not stable on Mars surfaces due to low temperature and pressure conditions, but it may potentially be formed and stabilized through deliquescence of salts in the subsurface [1, 2]. Our preliminary findings suggest that the presence of hygroscopic divalent salts (e.g., CaCl2, MgCl2) enhances thewater sorption of nontronite, even at low water vapor pressures at 25 °C. Additionally, our Raman results revealed that nontronite in CaCl2 solution retained briny water better than other nontronite-salt mixtures (e.g.,NaCl, MgCl2) at -100 °C. This study revealed the complex roles of nontronite and various salts ability to form and retain briny water in an extended temperature range (-100 to 25 °C). It also offers essential insights to the aqueous (geo)chemical history of Mars and the search for potential water resources for future human explorations to Mars.

This study presents the fabrication of double-layer electrospun nanofibrous membranes (DL-ENMs) using polyvinylidene fluoride (PVDF) and polyether sulfone (PES) based polymers with different degrees of hydrophilicity (PES, sulfonated PES, and PES with hydroxyl terminals). A comparative analysis was carried out with single-layer electrospun nanofiber membranes (SL-ENM) with a total thickness of about 375 μm. Using feed solutions, including sodium chloride, sodium nitrate, and simulated nuclear wastewater (SNWW), the performance of DL-ENMs was evaluated for desalination and radionuclide decontamination by direct contact membrane distillation (DCMD) and air gap membrane distillation (AGMD) techniques. The results showed that DL-ENMs, especially those incorporating a sulfonated PES-based hydrophilic layer, exhibited superior permeate fluxes, reaching values of 72.72 kg/m²h and 73.27 kg/m²h in the DCMD using aqueous feed solutions of NaCl and NaNO₃, respectively, and 70.80 kg/m²h and 41.96 kg/m²h using aqueous feed solutions of SNWW in DCMD and AGMD, respectively. Both SL-ENMs and DL-ENMs exhibited high rejection efficiencies and decontamination factors for the feed solutions (>99.9%). In addition, the prepared ENMs were exposed to gamma radiation to evaluate their applicability in real-life applications. The result of irradiation revealed the negative impact of gamma radiation on the fluorine content of PVDF which could be a critical point in using PVDF as a hydrophobic material for decontaminating nuclear wastewater by membrane distillation.

Hydrophilic nanosized minerals exposed to air moisture host thin water films that are key drivers of reactions of interest in nature and technology. Water films can trigger irreversible mineralogical transformations, and control chemical fluxes across networks of aggregated nanomaterials. Using X-ray diffraction, vibrational spectroscopy, electron microscopy, and (micro)gravimetry, we tracked water film-driven transformations of periclase (MgO) nanocubes to brucite (Mg(OH)₂) nanosheets. We show that three monolayer-thick water films first triggered the nucleation-limited growth of brucite, and that water film loadings continuously increased as newly-formed brucite nanosheets captured air moisture. Small (8 nm-wide) nanocubes were completely converted to brucite under this regime while growth on larger (32 nm-wide) nanocubes transitioned to a diffusion-limited regime when (∼0.9 nm-thick) brucite nanocoatings began hampering the flux of reactive species. We also show that intra- and inter-particle microporosity hosted a hydration network that sustained GPa-level crystallization pressures, compressing interlayer brucite spacing during growth. This was prevalent in aggregated 8 nm wide nanocubes, which formed a maze-like network of slit-shaped pores. By resolving the impact of nanocube size and microporosity on reaction yields and crystallization pressures, this work provides new insight into the study of mineralogical transformations induced by nanometric water films. Our findings can be applied to structurally related minerals important to nature and technology, as well as to advance ideas on crystal growth under nanoconfinement.

Water films captured in the interlayer region of birnessite (MnO2) nanosheets can play important roles in biogeochemical cycling, catalysis, energy storage, and even atmospheric water harvesting. Understanding the temperature-dependent loadings and properties of these interlayer films is crucial to comprehend birnessite reactivity when exposed to moist air and temperature gradients. Using vibrational spectroscopy we show that birnessite intercalates one water (1W) monolayer at up to ∼40 °C, but that loadings decrease by half at up to 85 °C. Our results also show that the vibrational properties of intercalated water are unaffected by temperature, implying that the hydrogen bonding network of water remains intact. Using molecular simulations, we found that the lowered water storage capacity at high temperatures cannot be explained by variations in hydrogen bond numbers or in the solvation environments of interlayer K+ ions initially present in the interlayer region. It can instead be explained by the compounded effects of larger evolved heat, as inferred from immersion energies, and by the larger temperature-driven mobility of water over that of K+ ions, which are electrostatically bound to birnessite basal oxygens. By shedding new light on the temperature-driven intercalation of water in a nanolayered mineral, this study can guide future efforts to understand the (geo)chemical reactivity of related materials in natural and technological settings.

Visualisation of molecular representations is an important area within chemistry education that has been explored for a long time, from several different perspectives. In the 1950s, Linus Pauling and Robert Koltun defined the CPK-model, describing the colours of the different atoms used in wood or plastic ball-and-stick models, for example, the black carbon, the white hydrogen, and the red oxygen. These analogue ball-and-stick models (e.g., MolyMod) are still used both in schools and at universities to help students “see” chemistry in three dimensions (3D). Today, with digitalisation, new tools are available to represent and visualise chemistry(Bernholt, Broman, Siebert, & Parchmann, 2019). With these modern digital tools, there are less limitations in molecular size to represent molecules, and even large structures and reaction mechanisms can be explored (Won, Mocerino, Tang, Treagust, & Tasker, 2019). In our project, interventions applying Virtual Reality (VR) as the digital tool during organic chemistry workshops and tutorials, have been explored related to cognitive and affective learning.

VR gives students the possibility to practice spatial ability, i.e., to move between 2D and 3D. In textbooks, chemistry is presented in 2D using, for example, Lewis structures. However, in real life, chemistry is three-dimensional, and the move between 2D and 3D is something students, as novices, need to practice to understand why and how chemicals react. In our project, university students practice their spatial ability through the application of VR. This on-going project started in 2018, and different workshops and tutorials have been implemented in different chemistry courses for bachelor, master, and engineering students. As presented in previous recent research from Brown and colleagues (2021), our students were very positive, enthusiastic and engaged to work with VR to develop their spatial ability and to visualise chemistry. In the presentation, we will give examples on how students can improve their learning and interest with the use of VR to represent chemical structures.

One of the fundamental aspects of chemistry learning is to visualize chemical structures. Through the application of Alex Johnstone's (1991) multilevel thought, the submicroscopic level is often a challenge for students, especially the shift between 2D and 3D, i.e., spatial thinking or spatial ability (Harle & Towns, 2011). With small molecules, plastic ball-and-stick models are commonly used, but on university level, the structures are often larger. By applying digital tools and techniques, as Virtual Reality (VR), there are less limitations in size to represent molecules, and even large structures and reaction mechanisms can be explored (Won et al., 2019). In a five-year design-based research project (Anderson & Shattuck, 2012), a collaboration between university chemistry teachers and a chemistry education researcher, has had an aim to develop university chemistry students' spatial thinking.

Students and teachers have, in workshops and tutorials, applied VR with both simple and more advanced tools, see figures 1 and 2. Empirical data has been collected using surveys, interviews, and observations. Standard ethical considerations have been considered throughout the whole project.

In this presentation, students' cognitive and affective learning related to spatial thinking will be discussed, as well as students', teachers', and researcher’s perspectives from the application of VR to visualize chemistry will be elaborated further. Implications for chemistry teaching at all levels will also be explored.