Chemistry

This study focuses on the synthesis of Co_0.5Cu_0.5Fe₂O₄ mixed ferrites supported on nanoporous carbon materials. The carbon supports were derived from two mixtures: a mixture of spent motor oil and pine wood chips (designated as AC-A), and a mixture of spent motor oil and crushed coal obtained from the Chukurovo mine (designated as AC-B). Additionally, two types of carbon components—nanodiamond and graphene oxide—were used for the synthesis of nanosized ceria-based hybrid nanocomposites. The results revealed that the active phase deposited on the carbon supports consists of a complex mixture of finely dispersed ferrite nanoparticles as well as small CeO₂ crystallites in the case of hybrid nanocomposites. The dispersion and phase composition of the deposited copper–cobalt ferrites depends on the textural properties of the carbon supports. Among the investigated materials, the graphene oxide-modified composites exhibited the highest catalytic activity at 670 K, achieving a methanol conversion of 90%. Full article

Edible mushroom polysaccharides have attracted considerable attention because of their diverse biological activities, particularly their antioxidant potential. However, efficient extraction of these polysaccharides remains challenging due to the rigid chitin–β-glucan network of fungal cell walls. In this study, polysaccharides from Termitomyces albuminosus were extracted using hot water extraction (HWE), ultrasound-assisted extraction (UAE), and ultrasound-assisted aqueous two-phase extraction (UA-ATPE). Extraction conditions for each method were optimized using Box–Behnken response surface methodology, and the effects of different extraction strategies on polysaccharide yield, physicochemical properties, and antioxidant activity were systematically compared. Among the three methods, UAE produced the highest polysaccharide yield (110.32 ± 3.68 mg/g). The extraction strategy significantly influenced the molecular weight distribution and monosaccharide composition of the crude polysaccharides. The crude UAE extract was further purified by DEAE-52 anion-exchange chromatography, yielding the major antioxidant-active fraction eluted with 0.1 M NaCl (designated ATPs-0.1M), which was identified as an acidic heteropolysaccharide with an average molecular weight of 6.37 kDa and composed primarily of glucose, mannose, galactose, xylose, glucuronic acid, rhamnose, and fucose. In vitro antioxidant assays demonstrated that TAPs-0.1M exhibited stronger DPPH radical scavenging, hydroxyl radical scavenging, and ferric reducing activities than the other purified fractions under the tested conditions. The results indicate that different extraction strategies are associated with distinct physicochemical characteristics and antioxidant activities of T. albuminosus polysaccharides. These findings provide a practical basis for selecting appropriate extraction methods and support the further development of T. albuminosus polysaccharides as natural antioxidant ingredients. Full article

Polymers based on tricyclic decane skeleton in the role of high-performance polycarbon, polyester, polyacrylate, etc., are used in optical equipment, dental restoration, photoresist, and other fields because of their rigid ring structure and corresponding excellent heat/weather/impact/scratch resistance. The preparation process of monomer tricyclodidecane dimethanol is complex and has engineering safety problems. Also, it has been monopolized by a few enterprises for a long time, and the price is expensive. There is a lack of systematic reviews on the synthesis of tricyclodecane dimethanol. In this paper, focusing on the preparation process of tricyclic decane dimethanol, the preparation process of bicyclic decane dimethanol to be prepared by dicyclopentadiene is summarized, including the reaction path, catalytic system and separation method, and the homogeneous catalysis, aqueous/organic two-phase catalysis and heterogeneous catalysis in the hydroformylation of high-carbon olefins are discussed, as well as the difference between stripping, extraction, membrane separation and other methods in the separation methods of catalyst and product. Then, the current research status at home and abroad is summarized, and the advantages and disadvantages of the above reaction methods are analyzed according to the reaction system, catalyst used, solvent, reaction conditions, and final reaction level. Finally, the downstream application and market of tricyclic decane dimethanol are analyzed. It provides a reference for the design and optimization of the preparation process of tricyclodecane dimethanol. Full article

This research examines the dyeing of cotton fabric using a natural dye, extracted from Bombax ceiba flowers, aiming primarily to carry out the entire dyeing process without conventional inorganic mordants. The dye was extracted in an alkaline medium, while three agricultural waste-derived bio-mordants, eucalyptus bark, onion peel, and aloe vera peel, were used to enhance the functional textile properties. These natural tannin-based mordants and phenolic mordants enabled the uptake of dye in an efficient way without releasing toxic chemicals, unlike the conventional metallic mordants. Various concentrations of each mordant were used in the preparation of dyed cotton samples, while NaCl was added in different concentrations to boost the exhaustion process. Among the three types of mordants tested, eucalyptus bark provided the best results, giving samples with a high washing fastness (rating of 4–5) and good rubbing fastness (rating of 3–4 on the gray scale). The progressively darker peach colors were achieved by adding more concentration of the eucalyptus mordant. Onion peel-mordanted samples ranged in color from dark yellow to orange, whereas aloe vera led to a unique peach color. Given the inherent antibacterial and antioxidant properties of Bombax ceiba, the dyed fabrics also possessed functional bioactive characteristics, which were further improved by the addition of bio-mordants. Furthermore, the ultraviolet protection factor (UPF) of the dyed fabric was approximately threefold higher than that of the undyed fabric, indicating a significant enhancement in UV-shielding performance after dyeing. This study conclusively demonstrates that bio-mordants serve as eco-friendly alternatives to chemical mordants, offering excellent colorfastness, diverse aesthetic possibilities, and functional properties, thereby supporting sustainable textile coloration practices. Full article

Amyloidosis encompasses a spectrum of diseases in which insoluble protein aggregates are deposited in various parts of the body, including the brain, giving rise to Alzheimer’s disease, prion disease, and Parkinson’s disease, and also being a manifestation of Type II diabetes. The soluble protein gets aggregated as insoluble plaques by an unknown phenomenon, leading to the disease. If an agent is developed that can dissociate or disintegrate these plaques, it can be proposed as a lead molecule for amyloid dissociation. In the present study, we have taken the aqueous extract of a herb, Shankhapushpi (Convolvulus pluricaulis), and synthesized zinc oxide nanoflowers (ZnO-NFs-Skp). The plant extract was characterized using phytochemical analysis, and the ZnO-NFs-Skp were characterized using various photophysical tools like dynamic light scattering, zeta potential, XRD, FTIR, and scanning electron microscopy (SEM). The in vitro cytotoxicity of the ZnO-NFs-Skp was assessed in the PC12 cell line using an MTT assay and a fluorescent dual-staining assay. The effect of ZnO-NFs-Skp on zebrafish embryos was evaluated for in vivo biocompatibility. Finally, the amyloid degradation of the ZnO-NFs, after incubation with preformed insulin amyloids, the model amyloid protein used for the amyloid study, was evaluated at different time intervals using the Thioflavin T fluorescence assay. The results indicated that the Shankhapushpi extract had alkaloids, coumarins, and glycosides. The hydrodynamic diameter of ZnO-NF-Skp was found to be 181 nm, and the zeta potential was −17.7 mV. SEM imaging showed a carnation flower-like morphology with a petal thickness of 30 ± 5 nm. The ZnO-NFs-Skp did not induce any toxicity up to a dose of 160 μg/mL, both in vitro and in vivo. The amyloid degradation study revealed 38% degradation of the IA, 24 h after incubation at 37 °C. SEM analysis also evidenced the degradation of IA. Compared to ZnO nanoparticles (18%), ZnO-NFs-Skp could degrade almost double (35%) the amount of IA after 12 h incubation, as shown by the ThT assay. Overall, the data suggested that Shankhapushpi-mediated ZnO-NFs (ZnO-NFs-Skp) are biocompatible and have a good capacity to degrade amyloids. In the future, amyloid degradation using Aβ-42 and the prion protein needs to be investigated. Full article

Understanding the mechanical behavior of bimetallic nanoparticles under compressive stress is relevant for the use of these nanostructures in catalysis and nanomechanics. In this work, we present molecular dynamics (MD) simulations of compressive deformation in Pt–Ni nanoparticles—and bulk systems for comparison—with varying compositions (Pt_xNi_1−x) and local distributions. The simulations show that the mechanical response is governed by local strain fields, which influence both elastic and plastic regimes. The final trajectories were analyzed by dislocation analysis (DXA), simulated STEM imaging, and geometric phase analysis (GPA), which allowed the obtention of high-resolution strain maps. Analysis of von Mises stress distribution allowed us to correlate composition and atomic ordering with the formation and evolution of dislocations in the nanoparticles. The Pt_0.5Ni_0.5 intermetallic compound exhibits superior mechanical performance under uniaxial compression; in bulk, this composition also shows enhanced elastic energy storage. In polycrystalline nanoparticles, energy dissipation increased with decreasing average grain size, which is attributed to elevated plastic activity induced by the presence of multiple crystallographic orientations. GPA results show that it is possible to discriminate between compositions differing by as little as $\mathrm{\Delta }x$ = 0.1 based on local strain distributions, and the comparison with GPA performed on real STEM micrographs gives a fair agreement. GPA and atomistic stress maps reveal how strain fields evolve during compression and how they correlate with the development of plasticity. These findings highlight the critical role of local structural heterogeneities in dictating the mechanical behavior of nanoscale Pt–Ni systems, and provide strong evidence that GPA can correlate local strain and composition in real high-resolution micrographs. Full article

Direct comparisons of MnO₂ polymorphs in synthetic benzylic oxidation remain limited, particularly regarding the combined effects of crystallinity, morphology, surface area, and surface-associated water. In this study, α-, β-, and γ-MnO₂ were prepared by hydrothermal methods and benchmarked against nano-MnO₂ for the oxidation of diphenylmethane to benzophenone. XRD, TGA, FTIR, BET, and SEM analyses confirmed phase-defined crystalline polymorphs, distinct wire- or rod-like morphologies, and marked differences in surface area and water retention. Nano-MnO₂ exhibited a porous, poorly crystalline nanoscale structure with the highest surface area and delivered the greatest oxidation efficiency under aerobic, atmospheric, and anaerobic conditions. Among the crystalline phases, α-MnO₂ showed the highest activity despite its lower BET surface area than β-MnO₂, indicating that surface-associated water is more influential than surface area alone. The loss of activity after drying at 120 °C, prolonged storage, or reuse further supports the critical role of labile surface-bound water. Overall, this work establishes a structure–morphology–water–reactivity relationship for MnO₂-mediated arylmethylene oxidation and identifies water-rich nano-MnO₂ as the most effective material for converting benzylic substrates to ketones. Full article

Citrus fruits are a significant source of flavonoids. Of all the citrus fruits, Citrus paradisi (grapefruit) presents the highest concentration of the flavonoid naringin, a compound offering a variety of human health benefits and applications in the pharmaceutical, food, and cosmetic industries. Commonly, when a citrus fruit is consumed, the peel and seeds are discarded, resulting in approximately 50% waste, making the potential use of citrus waste in order to reduce environmental impact a research priority. The present study used fresh grapefruit albedo to extract naringin via eco-friendly methods, such as ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE), which were compared against the conventional reflux extraction procedure. Furthermore, the presence of naringin was confirmed by nuclear magnetic resonance (NMR) spectroscopy, while naringin content was determined via HPLC-DAD analysis. The results obtained show that the pink grapefruit variety was the optimal source for extracting the flavonoid of interest, producing the highest content (3.41 g/kg), followed by the red (2.47 g/kg) and white (1.70 g/kg) varieties. The UAE method was observed to reduce the extraction time significantly, to only 10 min, which is up to 30-and -fold less than the extraction times obtained using conventional (5 h) and MAE (40 min) methods, respectively. These results prove the usefulness of UAE as a simple, fast, efficient, and eco-friendly method for extracting naringin from fresh grapefruit albedo, via the use of a green solvent such as ethanol. In addition, the present study is the first to conduct a comparative analysis of naringin content in the three main grapefruit varieties grown in Mexico. Full article

Global requirement of clean, cost-effective and sustainable energy has stimulated massive research and development in photocatalytic materials that have the potential to harvest solar based energy while mitigating the environmental issues. Among various materials, perovskite oxides have emerged as a promising energy resource. Owing to the structural versatility, optical and electrical properties, chemical inertness allows the use of material of multifunctional prospects. Currently Strontium titanate (SrTiO₃), a vital perovskite oxide having a band gap nearly ~3.2 eV, is showing significant function for photocatalytic water splitting, carbon dioxide conversion and degradation of organic pollutants. Though within the UV spectrum, its intrinsic photocatalytic behavior is limited to approaches such as graphene junctions, noble-metal support, and post-synthetic heat treatment seem to promote the adsorption within visible-light. Strontium titanate also demonstrates photo charge separation efficiency, and long-term catalytic durability. Moreover, modifications and hydrothermal synthesis have proven extremely efficient for nano-based engineering, control over crystal diameter, defects, and shape, which can result in magnificent composites that can be promising substitutes. Therefore, further research is imperative regarding these material application prospects. This comprehensive review provides insights into details on the potential of nanoengineering and composite approaches to reduce the inherent limitations of perovskite oxides, especially Strontium titanate, and enabling additional applications in next-generation photovoltaic and solar energy harvesting technologies. Full article

Natural coumarins are a structurally privileged group of bioactive benzopyranone lactones widely spread across the Apiaceae, Rutaceae, and Leguminosae families, and hold significant potential as inhibitors of pathological protein aggregation in Alzheimer’s disease, Parkinson’s disease, and type 2 diabetes mellitus. The fully planar, rigid bicyclic structure of the coumarin nucleus (~3.4–3.5 Å thickness) is geometrically compatible with intercalative π–π stacking with aggregation-nucleating aromatic residues, including Phe19 of Aβ(1–42), providing a mechanistically coherent pharmacophoric basis for anti-aggregation activity according to computational and indirect biophysical evidence. This review critically evaluates the peer-reviewed literature on naturally occurring coumarins and their synthetic derivatives as candidate β-sheet intercalators, with analysis of SAR at C-3 to C-8 positions; multi-target-directed ligand designs with dual activities of inhibiting AChE, BACE-1, GSK-3β, and MAO-B, and as blood–brain barrier-penetrating neuroprotective agents validated in cellular and rodent models. The critical analysis identifies the translational gap between in vitro IC₅₀ values and attainable brain drug concentrations as the primary pharmacological obstacle. It identifies the absence of systematic investigation of coumarin against IAPP, a directly relevant amyloid target in metabolic neurodegeneration, as the most significant unmet research priority in the field. Full article

Antibiotic resistance has emerged as a major global health challenge, underscoring the urgent need for alternative therapeutic strategies capable of enhancing the efficacy of existing antibiotics. In this context, saponin-based nanomaterials have attracted considerable attention due to their potential as antibiotic-modulating systems. This study investigated a saponin-enriched fraction obtained from the bark of Sarcomphalus joazeiro Mart. (SEF-4), its application in the green synthesis of silver nanoparticles, and the antibiotic-modulating potential of the resulting nanoformulation. SEF-4 was obtained from the ethanolic bark extract through liquid–liquid partitioning (52% yield), followed by column chromatographic purification and chemical characterization using LC-ESI-QTOF-MS. The purified fraction was subsequently employed as both a reducing and stabilizing agent for the synthesis of silver nanoparticles (putative AgNP-SEF-4), which were physicochemically characterized. Antibacterial activity and antibiotic-modulating effects were evaluated using the broth microdilution method against standard and multidrug-resistant bacterial strains. LC-ESI-QTOF-MS analysis enabled the putative identification of five jujubogenin-type triterpenoid saponins bearing tetra-, penta-, and hexasaccharide moieties with distinct glycosylation profiles; however, the precise sugar sequence, monosaccharide composition, and glycosidic linkage positions remain to be confirmed through complementary NMR and hydrolysis studies. Although neither SEF-4 nor putative AgNP-SEF-4 displayed clinically relevant intrinsic antibacterial activity, the nanoformulation significantly enhanced the activity of aminoglycoside antibiotics. The most pronounced modulatory effects were observed against Klebsiella pneumoniae ATCC 1705 in combination with amikacin and against both standard and multidrug-resistant Escherichia coli strains when combined with gentamicin or amikacin. These findings highlight the potential of putative AgNP-SEF-4 as an antibiotic adjuvant capable of potentiating aminoglycoside efficacy and increasing bacterial susceptibility, including in multidrug-resistant strains. Full article

The nucleophilic properties of the isolated dicyanoaurate(I) anion in σ-hole interactions were investigated using theoretical calculations of models from 19 crystalline literature structures. The study focuses on the ability of [Au(CN)₂]⁻ to participate in various noncovalent interactions, including halogen, chalcogen, pnictogen, and tetrel bonds. The research reveals that both nitrogen atoms of the cyanide ligands and the gold(I) center exhibit nucleophilic behavior. The nature of all interactions and philicities of interacting atoms were confirmed using a set of theoretical methods, including QTAIM topological analysis, noncovalent interaction plots (NCIplot), electrostatic potential (ESP) surfaces, electron localization function (ELF), analysis of electron density (ED), and electrostatic potential (ESP) minima in their 1D profiles along the bond paths, BSSE corrected dimerization energies, and NBO charge-transfer analysis. The study demonstrates that the dicyanoaurate(I) anion can act as a versatile building block in supramolecular chemistry, participating in multiple types of noncovalent interactions through different sites, including first confirmed examples of gold(I)-involving intermolecular chalcogen bonds. Full article

A series of 7-aminopyrazolo[1,5-d][1,2,4]triazin-4(5H)-ones was synthesized via a cascade condensation of methyl aroylpyruvates with 1,3-diaminoguanidine hydrochloride. The scope and limitations of this approach were investigated. Methyl mesitoylpyruvate bearing a sterically hindered mesityl substituent diverted the reaction pathway, affording a 1,2,4-triazine derivative. Diethyl 2,4,6-trioxoheptanedioate resulted in an unexpected pyrazolo[1,5-d][1,2,4]triazepine scaffold. All synthesized compounds were evaluated for growth-regulating activity using the green microalga Chlorella vulgaris as a model organism. 7-Amino-2-(4-methoxyphenyl)pyrazolo[1,5-d][1,2,4]triazin-4(5H)-one has shown the best results in the initial microplate screening, showing increased cell density at 10 μmol/L. However, subsequent validation in 50 mL flask cultures revealed no significant effect on biomass accumulation, photosynthetic pigment content, carbohydrate levels, or neutral lipid production compared to the negative control. Only a modest increase in protein content was observed at the concentration of 100 μmol/L. Full article

CsPbI₂Br, an all-inorganic cesium–lead mixed-halide perovskite, has established itself as a leading contender for next-generation photovoltaics, owing to its near-optimal direct bandgap, exceptional thermal stability, and favorable optoelectronic characteristics. These attributes make it a versatile candidate for both high-efficiency single-junction devices and wide-bandgap top cells in tandem architectures with silicon or low-bandgap perovskites. However, the commercialization of CsPbI₂Br perovskite solar cells (PSCs) is severely hindered by inherent interfacial challenges, including halide segregation under operational stress, high density of interfacial defects, energy-level misalignment between the perovskite and charge transport layers (CTLs), and chemical incompatibility at hetero-interfaces. These factors limit power conversion efficiency (PCE) and long-term operational stability. Interface engineering has thus become the pivotal strategy to address these bottlenecks, enabling transformative improvements in device performance. This review comprehensively summarizes the state-of-the-art interface engineering strategies for CsPbI₂Br PSCs, including molecular passivation, construction of 2D/3D heterostructures, design of composite interlayers, and development of dopant-free, stable CTLs. The underlying mechanisms of defect passivation, non-radiative recombination suppression, energy-level alignment optimization, and ion migration inhibition are systematically elucidated. Furthermore, we discuss critical remaining challenges, including the trade-off between phase stability and optoelectronic quality, interfacial delamination due to thermal expansion mismatch, and scalable fabrication of interface-modified large-area devices. Finally, future research directions are proposed, emphasizing the development of multifunctional interfacial materials, all-inorganic interface architectures, in situ characterization combined with computational modeling, and integration into tandem photovoltaic systems. By consolidating current knowledge and highlighting promising frontiers, this review aims to guide the rational design of high-performance, stable, and commercially viable CsPbI₂Br PSCs, accelerating their role in the global transition toward renewable energy. Full article

Sustainable water remediation requires catalytic strategies that remove contaminants efficiently while reducing chemical input, byproduct formation, and ecological disturbance. Conventional radical-dominated advanced oxidation processes can rapidly degrade pollutants, but their reliance on high oxidant dosages and freely diffusing reactive oxygen species often causes matrix quenching, non-selective oxidation, low oxidant utilization, and potential ecological risks. Mild interfacial catalysis provides a materials-chemistry strategy to regulate oxidative intensity and direct contaminant transformation under environmentally relevant conditions. In this review, mild catalysts are defined by pathway-selective, interfacially confined, and environmentally compatible oxidation rather than by low dosage alone. Representative non-radical or low-intensity pathways, including singlet oxygen generation, surface-mediated electron transfer, high-valent metal–oxo species, and direct oxidative transfer processes, are discussed in relation to active-site structure, oxidant utilization, matrix tolerance, and byproduct control. We further summarize how coordination environments, defect chemistry, heteroatom configurations, nanoconfinement, and immobilized interfaces regulate reactive-species formation and interfacial charge transfer. Key material platforms, including single-atom catalysts, heteroatom-doped carbons, defect-engineered oxides, catalytic membranes, hydrogels, and floating or immobilized composites, are evaluated from mechanistic and application-oriented perspectives. Finally, catalyst regeneration, cost, microbial community responses, algae–bacteria balance, ecotoxicity, and long-term safety are discussed to guide sustainable aquatic ecosystem restoration. Full article

The structure, relative stability, spin-state preference, and preliminary oxygen-release behavior of small nickel–oxygen clusters, (NiO₂)_n (n = 1–4), were investigated using density functional theory at the M06-2X/def2-TZVP level of theory. Several initial topologies and spin multiplicities were explored to distinguish between dissociated Ni···O₂ solutions, bonded dioxo-like arrangements, and side-on metal–dioxygen motifs. For the monomer, the lowest-energy solution of the fully explored set corresponds to a non-bonded Ni···O₂ arrangement; however, when the analysis is restricted to chemically bonded NiO₂ minima, the linear high-spin O–Ni–O structure is the most stable configuration. The side-on η²-O₂ motif was found as a higher-energy bonded minimum, retaining an elongated O–O bond and therefore representing an activated dioxygen-like species. ELF and LOL analyses were used as complementary localization descriptors to distinguish between the electronically separated oxo-like domains of the linear structure and the more coupled localization pattern of the side-on dioxygen adduct. Aggregation from n = 2 to n = 4 suggests a transition from compact bridged motifs to more open Ni–O frameworks. However, the size-dependent trend is discussed only within the explicitly explored conformational space. Preliminary analysis of O₂ release from the tetramer indicates that oxygen evolution is not a simple dissociation event but involves substantial structural reorganization. Overall, the results support the view that small (NiO₂)_n clusters may behave as metastable oxygen-rich intermediates, while also highlighting the strong sensitivity of their energetic ordering to spin state, topology, and structural relaxation. Full article

Perillyl alcohol, a rare monoterpenoid, can be widely used in chemical, agriculture, and food industries and shows promise in medicine as an anticancer agent. The artificial synthesis of perillyl alcohol from β-pinene epoxide using inexpensive and abundant turpentine is chosen for improving its pharmaceutical and industrial applications. This work presents a green and sustainable catalytic process for the rearrangement of β-pinene epoxide to perillyl alcohol. A novel ammonium phosphomolybdate solid acid (AC-COIMI-NH₄PMo) was built via phosphomolybdic acid chemisorption onto an N-basylous site of imidazolized activated carbon followed by ammonia fumigation, which exhibits outstanding catalytic performance in the rearrangement of β-pinene epoxide to perillyl alcohol in nitromethane under mild conditions. At 80 °C over 80 min, nearly complete conversion of the epoxide is achieved with a perillyl alcohol selectivity of 77.3%. Moreover, the used catalyst can be readily recycled after washing with hot nitromethane. The favorable proton-donating capacity of nitromethane for the rearrangement and the comparison of adsorption energies between substrates and main products on ammonium phosphomolybdate are revealed through DFT calculation. Kinetic analysis based on the Langmuir adsorption model indicates that the surface reaction of strongly adsorbed β-pinene epoxide is a rate-determining step and follows a zero-order reaction process; the activation energy is 29.64 kJ/mol within the temperature range of 50–80 °C. Finally, a parallel catalytic rearrangement mechanism is proposed, and an eight-step reaction pathway toward perillyl alcohol is elaborated for β-pinene epoxide conversion on AC-COIMI-NH₄PMo. Full article

Access to clean and safe drinking water for all remains a global challenge, mainly for rural populations and areas affected by natural disasters or humanitarian crises. The traditional water quality treatment technologies can work well in laboratory or controlled settings, but they are usually applied under conditions unavailable in these types of conditions. Traditional water quality treatment methods are limited by established infrastructure, expensive operating costs, energy requirements, and the ability to perform in-field water treatment. To improve the barriers of traditional water quality treatment technologies, recently developed scientific discoveries of nanozymes, a new class of nanomaterials with enzyme-like catalytic activity, have shown the ability to decentralise water purification. Nanozymes provide a mechanism for water treatment that does not require the infrastructure or the cost of traditional water quality treatment methods. Also, nanozymes possess extremely high catalytic activity, chemical stability, are inexpensive, and are suitable for a variety of contaminants. This review gives a systematic overview of the development of suitable nanozyme-based portable water purification systems. It shows their catalytic mechanisms, the class of nanozymes used, and the design characteristics related to their working use, also highlighting the developments that consider the specific needs of rural contexts, provide rapid responses to disaster areas, and offer drinking water with reliable, simple, and sustainable apparatus. Full article

The chemical evolution of simple molecules into higher-order structures, such as amino acids, is a fundamental process occurring throughout the cosmos. Methane (CH₄) serves as a key precursor in this evolutionary sequence and is prevalent on planetary bodies like Mars and Saturn. In these environments, CH₄ is frequently ionized by cosmic radiation, forming the methane radical cation (CH₄⁺). In this study, the ion-molecule reactions between CH₄⁺ and neutral CH₄ (CH₄⁺ + CH₄ → products) were investigated using direct ab initio molecular dynamics (AIMD) simulations to elucidate the underlying reaction mechanisms. Our calculations demonstrate that proton transfer (PT) occurs efficiently, yielding the methanium ion (CH₅⁺) and the highly reactive methyl radical (CH₃): CH₄⁺ + CH₄ → CH₅⁺ + CH₃. Furthermore, the reaction outcomes exhibit a strong dependence on the impact parameter (b). Collisions at very low impact parameters (b = 0–0.2 Å) resulted in non-reactive, billiard-ball-like scattering. Within the range of b = 0.2–3.0 Å, the formation of a long-lived complex, [CH₅-CH₃]⁺, was observed. In the intermediate range of b = 3.0–5.0 Å, a proton-stripping mechanism predominated in PT channel, while collisions at b > 5.0 Å were exclusively non-reactive. The reaction mechanism was qualitatively discussed. These findings provide a detailed atomistic picture of the collision dynamics governing methane-derived molecular evolution in celestial environments. Full article