Computational insights into the corrosion inhibition mechanism of daidzein on Al(AA7075) alloy in NaCl solution: A DFT and molecular dynamics study.

MnOx media and biologically formed MnOx on sand surface from Mn(II) oxidation significantly promote dissolved aluminum removal in filtration systems.

Dental surface restoration using Ca-caseinate bio/nano colloids: Converged roughness parameters reveal heterogeneous tooth surface reactivity.

Boosting the adsorption capacity/selectivity of graphene oxide membranes via photocatalytic perforation for water treatment

Precisely defect-engineered WSe2 nanosheets enable enhanced surface reactivity and charge transfer for robust, humidity-tolerant, and fast room-temperature NO2 sensing

Phase evolution matters: How Fe(II) reshapes coprecipitate surfaces for enhanced U(VI) adsorption.

Airborne brake wear particles (BWPs) are increasingly recognized as important non-exhaust contributors to urban particulate pollution; however, their inhalation toxicity and the key determinants of their pulmonary effects remain poorly defined. Two types of BWPs were generated using a brake dynamometer equipped with non-asbestos organic (NAO) and low-metallic (LM) brake pads on a cast-iron disc. The ≤ 2.5μm fractions of BWPs generated from the NAO and LM brake pads were designated NAO2.5 and LM2.5, respectively. SRM 2975 (diesel exhaust particles) and Fe2O3 nanoparticles were included as reference particles. The test particles were characterized for their physicochemical properties, including morphology, size, surface area, crystallinity, colloidal properties, chemical composition, and solubility. The intrinsic oxidative potentials (IOPs) of the test particles, evaluated using a cell-free 2',7'-dichlorodihydrofluorescein diacetate assay, ranked as NAO2.5 > SRM 2975 > LM2.5 > Fe2O3 on a mass basis, and as NAO2.5 > LM2.5 > SRM 2975 > Fe2O3 on a surface area basis. Pulmonary neutrophilic inflammatory responses were evaluated by bronchoalveolar lavage fluid analysis at 24h after pharyngeal aspiration of 25, 50, and 100µg/mouse in female BALB/c mice. On a mass basis, the inflammatory response ranked SRM 2975 > NAO2.5 > Fe2O3 > LM2.5 on a mass basis, whereas on a surface area basis, the ranking was NAO2.5 > LM2.5 > SRM 2975 > Fe2O3. Lung burden analysis at days 0, 1, and 28 after a single pharyngeal aspiration of 100µg/mouse showed relatively higher 28-day retention of NAO2.5 and LM2.5 (approximately 75% and 67%, respectively) compared to that of SRM 2975 (47%). These data indicate that NAO2.5 is more inflammogenic than LM2.5. Given that BWPs were larger and had substantially lower surface area than the reference particles, their stronger responses under surface area-based comparison suggest greater inflammatory potency per unit surface area. Overall, the BWPs examined in this study exhibited a toxicity profile not fully explained by IOP alone, suggesting an important contribution of particle-specific physicochemical properties.

In this study, raw and calcined eggshell-based biomaterials were modified with Ag⁺ ions, and their structural, surface, optical, and antimicrobial properties were systematically investigated. A sustainable approach was used to valorize eggshell waste, with AgNO₃ providing Ag-related species immobilized onto the material surface. X-ray diffraction confirmed the transformation of CaCO₃ to CaO upon calcination, while the absence of metallic silver peaks indicated incorporation of Ag⁺ within the nanocomposite. Zeta potential measurements showed increased positive surface charge after Ag⁺ modification, particularly in calcined samples, suggesting enhanced surface reactivity and colloidal stability. EDX analysis revealed localized Ag accumulation on non-calcined eggshells, whereas calcined composites exhibited more homogeneous Ag distribution. Photoluminescence studies showed green emission for ES@Ag⁺, while PL intensity was suppressed in C-ES@Ag⁺ due to Ag⁺-induced surface defects and charge transfer. Ag⁺ emission confirmed by UV-Vis. In addition, minimum inhibitory concentration (MIC) analysis revealed that ES@Ag⁺ exhibited superior antimicrobial efficiency at lower concentrations compared to C-ES@Ag⁺, demonstrating consistent performance across both liquid and solid media. Antimicrobial activity was tested against Candida albicans ATCC 10239 and Escherichia coli ATCC 8739 via the agar well diffusion method. ES@Ag⁺ exhibited inhibition zones of 17.00 ± 0.05mm and 16.00 ± 0.07mm, while C-ES@Ag⁺ showed 15.00 ± 0.02mm and 9.00 ± 0.05mm for C. albicans and E. coli, respectively. These results demonstrate the potential of Ag⁺-modified eggshell nanocomposites as sustainable materials for biomedical and environmental applications. While antimicrobial efficacy is promising, further cytotoxicity and biocompatibility studies are needed to assess safety and performance.

Ice surfaces play a central role in climate processes, astrochemistry, and materials science, yet their microscopic structure remains elusive. In particular, the degree of proton ordering at ice Ih surfaces critically influences surface reactivity, stability, and phase transitions. In this work, we employ advanced computational techniques─density functional theory to optimize equilibrium geometries, and many-body perturbation theory (GW and Bethe-Salpeter equation) to describe electronic and optical properties─to investigate ordered and partially disordered thin films of hexagonal ice (Ih). First, we analyzed six surface models featuring distinct arrangements of dangling OH bonds, quantified via an order parameter, and computed their Reflectance Anisotropy spectra, which exhibit a pronounced dependence on proton ordering. Among these, two representative models, the Ih-striped and Ih-low-ordered surfaces, emerge as the most stable. For these cases, we demonstrate that proton ordering governs the anisotropy of the optical response: the striped surface supports strongly directional excitonic states, in contrast to the nearly isotropic excitons observed in the low-ordered surface. Our results establish optical anisotropy as a robust fingerprint of proton order, providing a theoretical benchmark for polarization-resolved spectroscopic studies of ice. Furthermore, we show that excitonic effects serve as a sensitive probe of surface proton configurations, paving the way for experimental discrimination between competing models of ice surfaces under cryogenic conditions.

Metal intercalation and structural twisting are effective strategies for achieving precise control over the electronic properties, geometric configuration, and catalytic performance of layered materials. By regulating electron distribution and surface reactivity, these approaches facilitate reactant adsorption and subsequent activation, followed by coupling between surface species, thereby providing a versatile platform for the rational design of efficient and selective electrocatalysts. Based on this concept, we designed a twisted BC4N-TM-BC4N sandwich structure and systematically investigated its electrocatalytic performance for urea synthesis. After screening for stability and catalytic activity, 31 representative systems were identified and analyzed in terms of their electronic structures and catalytic behaviors. The results reveal that metal intercalation and twisting effectively modulate charge redistribution within the bilayer, enabling efficient electron transfer along the metal-B-N pathway and activating B sites to facilitate NO activation. This effect results in a marked decrease in reaction free energy, improves the adsorption process, and facilitates the coupling of NO and CO. Different metal systems exhibit optimal catalytic activity at specific twist angles, with most systems showing the best performance at 98.213°. Moreover, the majority of twisted systems demonstrate enhanced selectivity, indicating that this strategy improves both activity and selectivity simultaneously. Through SISSO-based machine learning, we derived a descriptor that quantitatively correlates catalytic activity to electronic properties as well as twist angle, exhibiting a robust linear relationship with Umax. This work delivers theoretical guidance for the rational construction of efficient and tunable urea electrocatalysts based on structural twisting and metal intercalation and offers valuable insights for the development of other multielectron coupling catalytic systems.

Vertically aligned tungsten diselenide (WSe2) nanosheets were synthesized via chemical vapor deposition and subsequently modified through nitrogen plasma treatment to obtain nitrogen-doped WSe2 (N-WSe2) with enhanced gas-sensing capabilities. The introduction of nitrogen dopants not only preserves the crystalline integrity of the WSe2 nanosheets but also significantly improves their electrical conductivity and surface reactivity. Chemiresistive gas sensors based on N-WSe2 demonstrate markedly enhanced sensitivity and lower detection limits toward both nitrogen dioxide (NO2) and ammonia (NH3) compared to their pristine counterparts. First-principles density functional theory calculations reveal that nitrogen doping introduces localized defect states that modulate charge transfer and spin polarization upon gas adsorption, thereby facilitating more efficient carrier modulation. This synergistic combination of structural alignment and electronic tuning offers a versatile strategy for engineering high-performance 2D TMD-based gas sensors for environmental and industrial monitoring applications.

Dangling OH bonds on ice surfaces are thought to play a central role in surface reactions relevant to planetary, interstellar, and prebiotic environments, yet their direct characterization is hindered by the intrinsic fragility of surface hydrogen-bonding networks, particularly under phase transition conditions. Here, using time-resolved in situ infrared reflection-absorption spectroscopy, we track the evolution of dangling OH bonds during the isothermal crystallization of amorphous solid water into ice I. We observe a transient excess of dangling OH bonds that gradually diminishes as the surface hydrogen-bonding networks reorganize, reflecting competition between nucleation-driven crystallization and surface stabilization. These findings provide direct spectroscopic evidence for a metastable surface state formed during amorphous solid water crystallization and uncover a surface-restructuring pathway that may influence the reactivity of icy surfaces.

The development of sustainable halogenation strategies remains a central challenge in synthetic chemistry, particularly for the preparation of aryl bromides, which are key intermediates in pharmaceuticals, materials, and cross-coupling transformations. Here, we report an atom-efficient photocatalytic bromination of electron-rich arenes enabled by a low-toxicity Ag-Bi double perovskite microparticles. Under mild conditions and using hydrobromic acid as a bromine source, the photocatalyst promotes highly selective mono-bromination of 1,3,5-trimethoxybenzene with excellent yields (up to 95.4%) and superior performance compared to the benchmark perovskite-like materials, such as CsPbBr3 and Cs3Bi2Br9. Mechanistic investigations reveal an unprecedented activation mode of the transformation, in which bromine radicals originate from the Cs2AgBiBr6 surface, as demonstrated by radical-trapping studies and catalyst degradation observed in the absence of HBr. Control experiments further rule out the involvement of oxidant species, confirming that surface-derived bromine radicals are regenerated by external bromide. The photocatalyst maintains activity over multiple cycles, retaining its structural integrity with only minor AgBr formation upon five consecutive runs. The method displays broad substrate scope, encompassing anisole derivatives, polymethoxylated arenes, and heteroaromatics, with regioselectivity governed by substrate properties. Overall, these findings highlight the unique reactivity of double-perovskite surfaces and open new avenues for sustainable photocatalytic halogenation chemistry.

Plastic composition drives the toxicity of UV-aged melamine-polypropylene microplastics, nanoplastics, and leachates on Raphidocelis subcapitata.

This review critically evaluates the recent progress in selectively functionalised graphene and its derivatives for the efficient removal of polycyclic aromatic hydrocarbons (PAHs) from aquatic systems. It begins by outlining the structural, electronic, and surface properties of graphene and its derivatives that underpin their environmental relevance. Functionalisation strategies are categorised into covalent and noncovalent approaches. Covalent modification introduces hydroxyl, epoxy, carboxyl, diazonium, nitrene, and peroxide groups onto the graphene lattice, enabling precise control over surface chemistry and reactivity. Noncovalent functionalisation, based on hydrogen bonding, electrostatic interactions, and π-π stacking, preserves the sp2 carbon framework while tailoring their interfacial affinity. Herein authors highlight how engineered surface chemistry enhances PAHs adsorption, a surface-dominated process governed by porosity, surface energy, and specific molecular interactions. Notably, graphene oxide functionalised with 9-aminoanthracene achieved removal efficiencies of 94%, 79%, and 74% for naphthalene, acenaphthylene, and phenanthrene, respectively, with sustained performance over repeated adsorption-desorption cycles. Owing to their hydrophobic and planar structures, PAHs strongly interact with graphene via π-π stacking. As carcinogenic and mutagenic priority pollutants, PAHs present serious environmental risks. The article further integrates the theoretical insights, addresses concerns of secondary contamination, and discusses challenges related to selectivity, regeneration, and long-term stability for sustainable remediation.

Hierarchical assembly of metal nanoparticles offers a powerful strategy to modulate catalytic performance, yet the interplay between nanoscale organization, surface accessibility, and facet-dependent reactivity remains poorly resolved. Here, we investigate how hierarchical organization of spherical silver nanoparticles governs catalytic performance by systematically correlating structure, facet distribution, and reaction kinetics. Bis(p-sulfonatophenyl) phenylphosphine (BSPP)-coated silver nanoparticles (AgNPs) were assembled into fractal (Ag fractals) and aggregate (Ag aggregate), and their catalytic activity was evaluated using sodium borohydride (NaBH4)-mediated reduction of organic dyes. Brunauer-Emmett-Teller (BET) analysis shows a decrease in specific surface area from AgNPs (138.1 m2 g-1) to Ag fractals (32.5 m2 g-1) and Ag aggregate (14.0 m2 g-1). The corresponding rate constants for rhodamine B (RhB) reduction follow the same trend (0.422, 0.278, and 0.061 min-1 for AgNPs, Ag fractals, and Ag aggregate, respectively). To probe the catalytic pathway, mechanistic studies were performed. Thiol-based surface passivation using cysteine and mPEG-SH (1 and 10 kDa) suppresses catalytic activity by >90%, while radical scavenging by p-benzoquinone (p-BQ) and metal ion chelation by ethylenediaminetetraacetic acid (EDTA) indicate a predominantly surface-mediated process involving electron transfer through radical intermediates, with minor contributions from dissolved Ag+ species. X-ray diffraction (XRD) reveals facet redistribution upon assembly, with Ag fractals enriched in stable {111} planes and Ag aggregates exhibiting broadened, low-intensity features indicative of structural heterogeneity, correlating with their lower catalytic activity relative to AgNPs. Together, these results show that catalytic performance in hierarchical silver assemblies is governed not solely by surface area but by the coupled effects of nanoscale organization and facet-dependent surface reactivity.

This study investigates the effects of shot peening (SP) on the wear behavior of laser powder bed fusion (L-PBF) manufactured Co-Cr-Mo alloys in as-built and heat-treated (HT) conditions. SP significantly increased surface hardness, reaching 685 HV via sub-structural refinement and strain-induced gamma-to-epsilon martensitic transformation (63.04% ɛ-HCP in HT + SP), confirmed by XRD analysis. The results show that the transformation-induced plasticity (TRIP) effect and dynamic work-hardening provide superior wear resistance (4.95 × 10 −5 mm 3 /Nm) in the HT + SP condition. Furthermore, SP-induced surface reactivity facilitates the formation of protective tribo-oxide films, thereby transitioning the mechanism into a self-lubricating regime. Wear test findings demonstrate that SP enhances surface integrity and may eliminate the need for post-process heat treatment in industrial and biomedical applications.

Perovskite oxides are a versatile class of materials with tunable electronic structures, making them attractive for catalytic applications, including the oxygen evolution reaction (OER). The surface reactivity of these oxides is closely tied to the electronic structure of transition metal cations, particularly their 3d orbital occupation, which can be modulated by interfacial engineering. In this work, we investigate how subsurface engineering influences the interaction of ultrathin LaCoO3 films with water vapor. Using (near) ambient pressure core-level spectroscopy, we observe distinct differences in hydroxyl affinity and Co valence response depending on the electronic structure imposed by the underlying layer. Ultrathin LaCoO3 films with a higher initial Co oxidation state show stronger hydroxyl affinity, while those with a lower Co valence show more significant electronic changes upon water exposure. Our findings demonstrate a form of "remote control" in surface chemistry, where subsurface electronic engineering dictates hydroxyl affinity and electronic response at the surface. This concept offers a new degree of freedom to optimize oxide-adsorbate interactions for (electro)catalysis.

We perform Density Functional Theory calculations to determine adsorption energies of small gas molecules ( H 2 , N 2 , NO, and CO) on defective, vacancy-laden, black phosphorene. Different configurations of single and double vacancies in the monolayer structure are considered, together with several possible adsorption sites onto them. The exchange–correlation interaction is treated within a van der Waals–corrected DFT framework using the Klimeš–Bowler–Michaelides (KBM) functional. This research aims to provide fundamental insights into how atomic vacancies can be engineered to tune phosphorene's surface reactivity, offering a broader understanding of its multifaceted applications.

A new synthetic strategy and associated mechanism have been developed, in which two carrier conduction channels of n- and p-type semiconductors on the surface of one material are automatically and advantageously selected during surface reactivity. The key step is to uniformly channel non-equilibrium metal oxides of CuOx and SnOx throughout the sample by applying a flame chemical vapour deposition technique for 5 s. Unlike the original SnO2 semiconductor and Cu metal, the resulting material possessed intermediate physicochemical properties. It has been demonstrated that an oxidising gas, NO2, and reducing gas, H2S, can be alternately adsorbed, which was facilitated by the automatic selection of p- or n-type channels. This solid-solution sensing method utilizing non-equilibrium compositions can be employed in other applications involving semiconducting metal oxide gas sensing, even at low temperatures.