Search Results (337)

A targeted modification approach involving the synthesis of Ce/C co-doped TiO₂ aerogels (CeCTi) via a sol–gel method combined with supercritical CO₂ drying and subsequent heat treatment is employed to enhance the photocatalytic CO₂ reduction performance of cost-effective and stable TiO₂ aerogels. The results demonstrate that the CeCTi exhibits a pearl-like porous network structure, an optical band gap of 2.90 eV, and a maximum specific surface area of 188.81 m²/g. The black aerogel sample shows an enhanced light absorption capability resulting from the Ce/C co-doping, which is attributed to the formation of oxygen vacancies. Under simulated sunlight irradiation, the production rates of CH₄ and CO reach 27.06 and 97.11 μmol g⁻¹ h⁻¹ without any co-catalysts or sacrificial agents, respectively, which are 82.0 and 5.7 times higher than those of the pristine TiO₂ aerogel. DFT reveals that C-doping facilitates the formation of oxygen vacancies, which introduces defect states within the calculational band gap of TiO₂. The proposed photocatalytic mechanism involves the light-induced excitation of electrons from the valence band to the conduction band, their trapping by oxygen vacancies to prolong the charge carrier lifetime, and their subsequent transfer to adsorbed CO₂ molecules, thereby enabling efficient CO₂ reduction, which is experimentally supported by photoluminescence measurements. Full article

Subsurface deposition determines whether soils, aquifers, or ocean sediment represent a sink or temporary reservoir for microplastics. Deposition is generally studied by applying the Smoluchowski–Levich equation to determine a particle’s sticking efficiency, which relates the number of particles filtered by sediment to the probability of attachment occurring from an interaction between particles and sediment. Sticking efficiency is typically measured using column experiments or estimated from theory using the Interaction Force Boundary Layer (IFBL) model. However, there is generally a large discrepancy (orders of magnitude) between the values predicted from IFBL theory and the experimental column measurements. One way to bridge this gap is to directly measure a microparticle’s interaction forces using Atomic Force Microscopy (AFM). Herein, an AFM method is presented to measure sticking efficiency for a model polystyrene microparticle (2 μm) on a model geomaterial surface (glass or quartz) in environmentally relevant, synthetic freshwaters of varying ionic strength (de-ionized water, soft water, hard water). These data, collected over nanometer length scales, are compared to sticking efficiencies determined through traditional approaches. Force measurement results show that AFM can detect extremely low sticking efficiencies, surpassing the sensitivity of column studies. These data also demonstrate that the 75th to 95th percentile, rather than the mean or median force values, provides a better approximation to values measured in model column experiments or field settings. This variability of the methods provides insight into the fundamental mechanics of microplastic deposition and suggests AFM is isolating the physicochemical interactions, while column experiments also include physical interactions like straining. Advantages of AFM over traditional column/field experiments include high throughput, small volumes, and speed of data collection. For example, at a ramp rate of 1 Hz, 60 sticking efficiency measurements could be made in only a minute. Compared to column or field experiments, the AFM requires much less liquid (μL volume) making it effortless to examine the impact of solution chemistry (temperature, pH, ionic strength, valency of dissolved ions, presence of organics, etc.). Potential limitations of this AFM approach are presented alongside possible solutions (e.g., baseline correction, numerical integration). If these challenges are successfully addressed, then AFM would provide a completely new approach to help elucidate which subsurface minerals represent a sink or temporary storage site for microparticles on their journey from terrestrial to oceanic environments. Full article

The role of the metal valence state on the surface properties of metal-loaded clay minerals in the adsorption/oxidative degradation of an antibiotic was investigated. Transitional metal cations and their zero-valent counterparts such as Fe⁰, Ni⁰, Co⁰ and Cu⁰ supported on montmorillonite were comparatively investigated for their interactions during adsorption and toxicity tests of antibiotic norfloxacin (NOF). UV-Vis spectrophotometric and Fourier transform infrared (FTIR) spectroscopic analyses confirmed the involvement of the hydroxyl and carboxyl groups and/or piperazinyl nitrogen of NOF in the complexation with metal cations. Ecotoxicological assessment using aquatic plants Lemna minor showed that the metal cations reduce the bioavailability of the organic pollutant and that the zero-valent metals display higher toxicity due to their specific interaction with NOF and clay mineral surface. This evaluation will provide insights into potential environmental impacts of the co-occurrence of antibiotics and metals and will certainly contribute to correlating the safety of the water treatment by assessing the residual toxicity and its fluctuations. Full article

Hexavalent chromium (Cr(VI)) is a carcinogenic and highly mobile pollutant in aquatic environments. In this study, three cerium-based metal–organic frameworks (Ce-UiO-66, Ce-UiO-66-NO₂, and Ce-MOF-808) were synthesized and evaluated for their ability to remove Cr(VI) from aqueous solutions. Among the frameworks studied, Ce-MOF-808 exhibited the highest adsorption capacity and was selected for detailed investigation. To elucidate its structure and adsorption behavior, Ce-MOF-808 was characterized using XRD, FT-IR, SEM-EDS, TG-DTA, XPS, and Zeta potential analyses. The zeta potential results showed that the adsorbent surface remained positively charged in the pH range of 2.8–8.6, enabling electrostatic attraction toward anionic chromate species. XPS further revealed valence transitions between Ce³⁺/Ce⁴⁺ and Cr(VI)/Cr(III), demonstrating the occurrence of partial redox transformation during adsorption. Batch experiments showed that the adsorption was strongly pH-dependent and favored acidic conditions (pH 2). The kinetics followed the pseudo-second-order model, whereas the isotherm data were better described by the Langmuir model, yielding a maximum adsorption capacity of 42.74 mg/g. Thermodynamic analysis indicated a spontaneous and exothermic process. Moreover, Ce-MOF-808 maintained high Cr(VI) uptake in real water samples, demonstrating its environmental applicability. Overall, Ce-MOF-808 is a promising redox-active adsorbent for efficient Cr(VI) removal in water treatment applications. Full article

This article contends that Sofia Coppola’s Priscilla (2023) uses digital filmmaking to re-animate the commodified image of Priscilla Presley, privileging surface and affect over historical realism. Though Coppola predominantly shoots on film, her decision to film Priscilla digitally—an adaptation of Presley’s memoir—marks a formal shift in her filmography aligned with her ongoing exploration of feminine interiority and aesthetic control. The film traces Priscilla’s life from her first encounter with Elvis Presley to their separation, presenting a visually stylized narrative that immerses viewers in what Walter Benjamin terms a phantasmagoria: a spectacle of commodification divorced from historical consciousness (The Arcades Project). Rather than striving for veracity, Coppola evokes a nostalgic atmosphere that re-members Priscilla through pre-circulated cultural images. This article examines Coppola’s often-criticized “flat” visual style in relation to the Freudian uncanny, i.e., the estrangement of the familiar through temporal and affective distortion. Coppola manipulates digital temporality—looping and flattening time—to produce an oneiric repetition that heightens the artifice of Presley’s image while emotionally distancing viewers. These formal strategies dissipate emotional depth but intensify aesthetic control. Finally, this article considers the political valences of Coppola’s digital aesthetics in a media landscape that both enables visibility and enacts erasure. Full article

TiO₂ nanoparticles were synthesized by a nitric acid-assisted sol–gel route using three different amounts of nitric acid (NA) (0, 0.05, and 0.10 mL HNO₃) to investigate how controlled acid addition influences their structural, optical, and photocatalytic behavior under visible-light irradiation. X-ray diffraction and Raman spectroscopy confirmed the formation of phase-pure anatase TiO₂, with slightly increased crystallinity and crystallite size upon NA incorporation. UV–Vis absorption and Tauc analysis revealed a systematic blue shift in the absorption edge accompanied by band-gap widening, attributed to electron–hole confinement and defect-state modification. Photoluminescence spectra showed enhanced visible emission with increasing acid content, indicating a higher density of oxygen vacancies and Ti³⁺ centers. SEM–EDX analysis verified homogeneous morphology, Ti–O stoichiometry, and the absence of extrinsic impurities. Although the TiO₂ sample prepared with 0.10 mL of HNO₃ (FNA) showed a wider band gap and slightly larger crystallite size, it still delivered the highest photocatalytic performance in methylene blue degradation, reaching about 74.8% removal after 240 min of visible-light exposure. This unexpected behavior can be explained by a defect-related mechanism in which NA promotes the formation of surface oxygen vacancies and Ti³⁺ sites. Because of these defects, new electronic states appear between the valence and conduction bands, allowing the material to absorb lower-energy light and improving how electrons interact with the dye. Full article

Recent text to image systems can synthesize Islamic heritage elements with high visual fidelity, but their outputs rarely translate into fabricable geometry or integrate into interiors without substantial redrawing. We present an end-to-end workflow that links historically grounded precedent retrieval, controllable tileable generation, semantic segmentation and vectorization, and geometry-aware mapping into Computer-Aided Design (CAD) environments. Contributions include the following: (i) a license-audited dataset schema and a retrieval classifier for common Islamic motif families and architectural elements; (ii) precedent retrieval via a ResNet 50 and Vision Transformer (ViT) embedding pipeline; (iii) a Low-Rank Adaptation (LoRA) tuned diffusion model that generates tileable motifs with motif/region controls; (iv) a raster-to-vector pipeline that enforces curve closure and minimum feature widths for CNC/laser fabrication; and (v) a rubric and domain metrics (symmetry coherence, seam/tileability error, spline closure and junction valence, UV distortion, feature width compliance) that quantify “depth of integration” beyond surface texture. Quantitative metrics and blinded expert ratings compare the workflow against strong parametric baselines, while scripts translate images to fabrication-ready vectors/solids across walls, ceilings, partitions, floors, and furniture. Cultural safeguards cover calligraphy handling, regional balance audits, and provenance/credit. The workflow advances heritage-aware generative design by carrying imagery across the last mile into buildable detail and by providing practical checklists for adoption in interior architecture and conservation. Full article

Functionalized nanochannels are crucial for achieving excellent ion transport properties and enable versatile applications such as ion gating, biosensing, and energy conversion. Conical single nanochannels were fabricated in single-ion-track polyethylene terephthalate (PET) membranes using the ion-track-etching method. Leveraging the high programmability of deoxyribonucleic acid (DNA) strands, a series of DNA molecules were designed to functionalize the outer surface at the tip region (small opening) of the conical PET nanochannels. This approach enabled precise regulation of both spatial charge distribution and steric hindrance on the outer surface, enabling the investigation of ion transport properties under the dominance of outer surface charge effects across ions of different valences. In contrast to the low-valence K⁺, the high-valence cation Ru(NH₃)₆³⁺ exhibited far greater enhancement in ionic current rectification (ICR) within PET films functionalized with DNA of varying charge densities. We used COMSOL simulations to corroborate that higher-valence ions exert more pronounced effects on ion transport in conical nanochannels with greater outer surface charge density. Furthermore, it was confirmed that the tip region plays a critical role in modulating the ion transport properties of conical nanochannels, thereby validating outer surface functionalization as a rational and efficient strategy. Full article

The renewable-energy-powered electrocatalytic CO₂ reduction reaction (CO₂RR) efficiently converts CO₂ into high-value chemicals and fuels, offering a promising approach to addressing environmental and energy sustainability challenges. This process is of immense significance for constructing a sustainable artificial carbon cycle. Cu-based catalysts exhibit remarkable catalytic activity and broad product selectivity in CO₂RR, which can be attributed to their excellent electrical conductivity, moderate adsorption energy, and unique electronic structure. This review comprehensively summarizes the advantages, practical applications, and mechanistic insights of Cu-based catalysts in CO₂RR, with a systematic based on recent advances in tuning strategies via electronic effects and structural design. Specifically, it emphasizes the influence of electronic structure tuning (electron-donating/-withdrawing effects and steric hindrance effects), active center tuning (single-atom catalysts, heterogeneous synergetic effects, and polymer modification), and surface structure (morphology effect, valence-state effect, and crystalline-facet effect) influences on catalytic performance. By rationally designing the catalyst structure, the adsorption behavior of reaction intermediates can be effectively regulated, thereby enabling the highly selective generation of target products. The objective of this paper is to provide a theoretical framework and actionable strategies for the structural design and catalytic performance optimization of Cu-based catalysts, with the ultimate goal of promoting the development and practical application of efficient CO₂RR catalytic systems. Full article

The presence of various drugs in wastewater has generated growing concern about the contamination of water bodies. This requires urgent attention and the development of effective methods for their degradation in aquatic ecosystems. The present study evaluates the efficiency of metformin (MET) degradation via various photochemical processes—photolysis, H₂O₂ photodecomposition, photocatalysis, and photo-Fenton—using iron-pillared bentonite clays (Fe-PILC) as a catalyst. The influence of radiation wavelength (254 nm and visible light) was investigated, while MET degradation, H₂O₂ consumption, and total organic carbon (TOC) removal were monitored as key response variables. Structural characterization confirmed successful pillaring, increasing the surface area of bentonite from 35 to 246 m²/g, with iron content at 11 wt. % quantified by atomic absorption spectroscopy. Fe₃O₄ and FeO were identified using XPS, and a 2.08 eV band-gap energy was revealed via diffuse reflectance spectroscopy. Experiments were conducted at environmentally relevant MET concentrations (13,000 ng L⁻¹) in a 0.1 L batch photoreactor at 25 °C. The results demonstrate that (i) photo-Fenton was the most efficient process to remove and mineralize MET (100% degradation after 10 min and 83% mineralization after 90 min); (ii) Fe-PILC is effectively activated at λ < 700 nm, enabling 75% mineralization under visible light; (iii) hydroxyl radicals and valence band holes were the primary oxidative species driving MET oxidation; and (iv) cyanoguanidine and carboxylic acids were identified as main oxidation by-products via UHPLC. Pseudo-first-order kinetic constants were determined for all processes, offering insight into their relative efficiencies. Notably, the rate constant for photo-Fenton under visible light (0.406 min⁻¹) was comparable to that under UV -light (0.545 min⁻¹), highlighting the potential of visible light-driven treatments. Therefore, this study demonstrated the metformin degradation capability of iron-pillared clays under both visible and UV light. Full article

This study provides a comprehensive investigation into the growth behavior of boron nitride (BN) buffer layers on Silicon carbide (SiC) substrates and their influence on interfacial band alignment. BN layers were deposited on semi-insulating SiC by RF magnetron sputtering with deposition times of 2.5, 5, and 7.5 min (these deposition times are specific experimental parameters to adjust the thickness of the amorphous BN layer, not intrinsic material properties of BN). Atomic force microscopy revealed that the surface roughness of the BN layers initially decreased and then increased with thickness, indicating an evolution from nucleation to continuous film formation, followed by surface coarsening. Transmission electron microscopy confirmed the BN thicknesses of approximately 3.25, 4.91, and 7.57 nm, showing that the layers gradually became uniform and compact, thereby improving the structural integrity of the BN/SiC interface. Band alignment was analyzed using the Kraut method, yielding a valence band offset of ~0.36 eV and a conduction band offset of ~2.34 eV for the BN/SiC heterojunction. This alignment indicates that the BN buffer layer introduces a pronounced electron barrier, effectively suppressing leakage, while the relatively small VBO facilitates hole transport across the interface. These findings demonstrate that the BN buffer layer enhances interfacial bonding, reduces defect states, and enables band structure engineering, offering a promising strategy for improving the performance of wide-bandgap semiconductor devices. Full article

In 3.5 wt% NaCl solution used to simulate seawater, the individual (self-corrosion) and coupled (galvanic) corrosion behaviors of TA22 titanium alloy and 304 stainless steel were systematically investigated at 25 °C, 35 °C, 45 °C and 55 °C. Post-corrosion surfaces were characterized by scanning electron microscopy (SEM), three-dimensional profilometry and X-ray photoelectron spectroscopy (XPS). The results demonstrated that elevating temperature decreased the compactness and protective quality of the passive film on both alloys, as indicated by increasing donor densities and positive shifts in flat-band potentials. Distinct pitting corrosion occurred on 304 SS above 45 °C. Upon galvanic coupling, the passive film on TA22 was modified in both structure and composition, exhibiting a decreased TiO₂ content and increased lower valence oxides (Ti₂O₃, TiO). The galvanic effect intensified with temperature, leading to progressively aggravated corrosion of 304 SS, characterized by increased pit density, diameter, and depth compared to its self-corrosion state. Full article

To address the challenges of complex composition, high chemical oxygen demand (COD) content, and the difficulty of treating organic wastewater from brewery wastewater, as well as the limitations of traditional Fenton technology, including low catalytic activity and high material costs, this study proposes the use of biochemical sludge as a raw material. Coupled with iron salt activation and mechanical ball milling technology, a low-cost, high-performance iron-doped mesoporous nano-sludge biochar material is prepared. This material was employed as a particle electrode to construct a three-dimensional electro-Fenton system for the degradation of organic wastewater from sauce-flavor liquor brewing. The results demonstrate that the sludge-based biochar produced through this approach possesses a mesoporous structure, with an average particle size of 187 nm, a specific surface area of 386.28 m²/g, and an average pore size of 4.635 nm. Iron is present in the material as multivalent iron ions, which provide more electrochemical reaction sites. Utilizing response surface methodology, the optimized treatment process achieves a maximum COD degradation rate of 71.12%. Compared to the control sample, the average particle size decreases from 287 μm to 187 nm, the specific surface area increases from 44.89 m²/g to 386.28 m²/g, and the COD degradation rate improves by 61.1%. Preliminary investigations suggest that the iron valence cycle (Fe²⁺/Fe³⁺) and the mass transfer enhancement effect of the mesoporous nano-structure are keys to efficient degradation. The Fe-O-Si structure enhances material stability, with a degradation capacity retention rate of 88.74% after 30 cycles of use. When used as a particle electrode to construct a three-dimensional electro-Fenton system, this material demonstrates highly efficiency in organic matter degradation and shows promising potential for application in the treatment of organic wastewater from sauce-flavor liquor brewing. Full article

In this study, we investigate the improvement of physical and electrical characteristics in 4H-silicon carbide (SiC) MOS capacitors using Aluminum Oxynitride (AlON) thin films fabricated via Plasma-Enhanced Atomic Layer Deposition (PEALD). AlON thin films are grown on SiC substrates using a high ratio of NH₃ and O₂ as nitrogen and oxygen sources through PEALD technology, with improved material properties and electrical performance. The AlON films exhibited excellent thickness uniformity, with a minimal error of only 0.14%, a high refractive index of 1.90, and a low surface roughness of 0.912 nm, demonstrating the precision of the PEALD process. Through XPS depth profiling and electrical characterization, it was found that the AlON/SiC interface showed a smooth transition from Al-N and Al-O at the surface to Al-O-Si at the interface, ensuring robust bonding. Electrical measurements indicated that the SiC/AlON MOS capacitors demonstrated Type I band alignment with a valence band offset of 1.68 eV and a conduction band offset of 1.16 eV. Additionally, the device demonstrated a low interface state density (D_it) of 7.6 × 10¹¹ cm⁻²·eV⁻¹ with a high breakdown field strength of 10.4 MV/cm. The results highlight AlON’s potential for enhancing the performance of high-voltage, high-power SiC devices. Full article

In the present work we investigate by first principles calculations the structural, electronic, and optical properties of alkyl, 1-alkenyl and 1-alkynyl C₈ moieties chemisorbed on hydrogen-terminated silicon nanowire oriented along the ⟨112⟩ direction. Our results disclose how the nature of the carbon–carbon bond contiguous to the Si surface influences the behavior of the system. While 1-alkynyl groups exhibit the strongest Si–C bonding, it is 1-alkenyl functionalization that induces the most significant enhancement in optical absorption within the visible range due to charge transfer. The charge transferred from the nanowire to the moiety confirms the electronic coupling of the two systems. We found that the highest occupied molecular orbital of the 1-alkenyl moiety lies only 0.3 eV below the valence band edge of the hydrogen-terminated silicon nanowire, enabling new low-energy optical transitions which are absent in both the unmodified silicon nanowire and the isolated molecule. These findings demonstrate a synergistic effect of functionalization. Our study provides valuable insights into the design of functionalized silicon nanostructures with tailored optical properties, with potential implications for applications in sensing, photonics, and energy conversion. Full article