Search Results (5,929)

Silica aerogel, a prototypical transparent nanoporous material with ultralow density and a widely tunable refractive index, is employed as a Cherenkov radiator for precision gamma-ray diagnostics in inertial confinement fusion experiments. However, its optical transmittance is highly sensitive to sol–gel chemistry. Here, silica aerogels were prepared from tetraethyl orthosilicate (TEOS), ethanol, water, and aqueous ammonia, followed by aging, solvent exchange, and supercritical drying. The study examined how catalyst, ethanol, and water concentrations regulate nanostructure and optical transmittance. Increasing ammonia content accelerated gelation, produced smaller framework particles, and enlarged the pore size and pore volume. These changes increased the transmittance at 550 nm from 79.6% for C1 to 84.9% for C7. Increasing ethanol concentration diluted TEOS and its hydrolysis products, extended gelation, and narrowed the particle-size distribution. The average particle size decreased from 21.79 to 17.01 nm, while the transmittance at 550 nm increased from 57.4% for E1 to 65.2% for E5. Water produced a non-monotonic response: insufficient water limited TEOS hydrolysis, whereas excessive water promoted structural heterogeneity. Intermediate water content provided the most favorable optical response. These findings define a process–structure–transmittance relationship in which formulation-dependent nanoscale network formation governs scattering losses and optical clarity. Full article

Vanadium dioxide (VO₂) is a prominent active material for reconfigurable nanophotonics because its reversible metal-insulator transition produces large changes in complex refractive index and electrical conductivity. The usable phase contrast, however, is not an intrinsic constant: it is governed by defect type and location, vanadium valence, oxygen stoichiometry, strain, crystallographic orientation, dimensionality, and the chemical, electrical, optical, and thermal boundary conditions imposed by interfaces. This focused narrative review develops a defect- and interface-centred framework linking VO₂ phase physics to device-level optical modulation. Bulk, surface, grain-boundary, and heterointerface defects are distinguished, together with their effects on carriers, V-V bonding, phase stability, optical loss, and cycling reliability. Epitaxial and polycrystalline films, ultrathin layers, and nanostructures are compared across the visible, near-infrared, mid-infrared, and terahertz ranges. Thermal, optical, electrical, electrostatic, electrochemical, ionic, strain, and ferroelectric activation pathways are then compared according to volatility, speed, retention, reversibility, and endurance. Representative free-space metasurfaces, guided-wave modulators, adaptive emitters, and photonic memories are benchmarked separately to avoid mixing incomparable performance definitions. The resulting analysis shows that optical modulation, insertion loss, thermal overhead, ambient stability, and endurance are coupled through the same defect and interface landscape. Progress, therefore, requires coordinated control of phase purity, local chemistry, interface energetics, thermal transport, and architecture-specific performance reporting. Full article

Natural functional polysaccharides are biodegradable, safe, and bioactive macromolecules that contribute significantly to food security. This review provides a systematic overview of their classification, structural characteristics, and applications in agricultural pest control and grain storage, with emphasis on their mechanisms of action and preparation methods. Key representatives including chitosan, alginate, β-glucan, and pectin function through multiple pathways: direct pest inhibition, induction of plant resistance, bioactive encapsulation, and physical barrier formation. Recent advances in extraction, purification, and advanced nuclear magnetic resonance (NMR) techniques—quantitative NMR (qNMR), diffusion-ordered spectroscopy (DOSY), and pure shift methods—are summarized. Challenges including batch-to-batch variability, high production costs, and regulatory hurdles are discussed and future perspectives on green production, precision structural tailoring, and nano-encapsulation are proposed. This review aims to guide the application of polysaccharide-based materials in insect pest management and food protection. Full article

In recent years, energy storage devices have had a lower energy density for supercapacitor devices. Fortunately, certain drawbacks limit the liquid-based battery-type aqueous zinc-ion hybrid capacitor electrodes. For this reason, zinc–manganese (Zn-Mn)-based zinc-ion hybrid supercapacitors (ZIHSCs) have been designed using a manganese-dioxide-functionalized carbon nanotube (MnO₂–f-MWCNT) battery-type cathode in a semi-solid gel–free-standing film electrolyte. Herein, as-prepared MnO₂–MWCNTs are synthesized and assembled for nanostructured cathode composite materials by a facile hydrothermal technique. In this work, MnO₂ nanorods with f-MWCNTs are applied to the electrode, resulting in a semi-solid-state gel film electrolyte realized by assembling the Zn-Mn hybrid capacitor. The materials’ physical–chemical conformation and their unique characteristics, crystalline structures, and different morphologies are studied through XRD, FE-SEM, FE-TEM, and XPS analysis. In this work, the design of major-source MnO₂-based materials for positive and battery-type zinc metal anode approaches, along with the electrochemical properties of MnO₂–MWCNT//Zn hybrid charge storage mechanisms, are evaluated. The coin-cell-type ZIHSC investigation of cyclic voltammetric (CV) curves and lower constant current charge/discharge (GCD) and electrochemical impedance (EIS) methods is also carried out. In addition, the maximum specific capacitance values, 339.98 mAh/g and 203.52 mAh/g, were observed for MnO₂–MWCNT//Zn and MnO₂//Zn at 0.2 mA/g, respectively. Finally, the higher cycling stability of MnO₂−f-MWCNT of a 94.15% capacity retention after 15,000 cycles was evaluated and compared to MnO₂//Zn of 73.05% retention in ZIHSC device applications. The assessment of electrochemical MnO₂ cathode-based Zn-Mn ZIHSC performance is applicable for future aqueous electrical energy storage devices. Full article

Nanostructured tungsten–copper (W–Cu) composites are promising materials for high-heat-flux components and advanced thermal management; however, their processing is limited by a high positive enthalpy of mixing of ~35.5 kJ/mol and weak interfacial bonding. This study provides a thermodynamic and kinetic justification for a technological route intended for 70W–30Cu and 75W–25Cu (wt.%) composites using high-energy mechanical activation and spark plasma sintering (SPS). CALPHAD-type calculations identified a critical copper activity plateau a_Cu ≈ 0.33 at 950 °C in the W-rich range, which favors the retention of submicron grains of 200–300 nm by limiting the chemical potential driving force for coarsening. Kinetic modeling via DICTRA predicted the formation of metastable interfacial diffusion zones with a characteristic width of 20–90 nm during short SPS holding times of 150–300 s, enabling the transition from mechanical interlocking to metallurgical bonding. Based on these calculations, a processing window of 950–1050 °C is proposed to achieve a target relative density of ≥97% and electrical conductivity of 35–45% IACS. The results provide a predictive framework for the experimental synthesis of nanostructured pseudoalloys with optimized conductive networks and reinforced tungsten skeletons. Full article

Rice husk (RH) is a renewable siliceous lignocellulosic waste providing a unique, greener and less toxic alternative to conventional synthetic polymeric precursors in the production of carbon-based materials for biomedical applications. In this work we studied the porous structure of RH-lignin-based activated carbon produced in the form of honeycomb carbon monoliths and assessed their potential as hemoadsorbents for blood purification in the treatment of patients with serious medical conditions, such as kidney failure and sepsis. To determine their clinical suitability for such an application, the hemocompatibility and cytotoxicity of the monoliths were investigated using the standard ISO guidelines. The monoliths did not cause any changes in the cell viability or cell lysis. High micro/mesoporosity and surface chemistry of the initial monolith-C, N- and P-doped nanostructured carbon honeycomb monoliths were established by low-temperature nitrogen adsorption (LTNA) studies, mercury porosimetry data (MIP), SEM/EDS analysis and FT-IR spectroscopy. The micro-mesoporous, activated carbon-based filtration/adsorbent prototype devices, in the form of three-dimensional (3D) carbon matrix, functionalized with ion-exchange amino- and phosphate groups and encased in polyolefin heat shrink cable sleeve, have been developed with the capacity to remove protein-bound uremic toxins (PBUTs), such us PCS and IS, as well as inflammatory cytokines (IL-6 and IL-8) from human plasma in a flowing model system. The ammoxidized monolith-N, derived from the monolith-C, had the highest removal efficiency (40.05% for PCS, and 28.4% for IL-6). By contrast, phosphorylated monolith-P demonstrated the highest removal efficiency (54.62% for IS, and 54.4% for IL-8), whilst the monolith-C has the lowest removal efficiency for these adsorbates. These results do not correlate with the LTNA and MIP study results, suggesting that the interaction of surface chemical functional groups with the solutes play key roles in the adsorption mechanism. The ion-exchange mechanism of PBUTs and inflammatory cytokine chemisorption by the monoliths, modified with surface N- and P-containing functional groups, has been proposed. Full article

Significant research efforts have recently focused on nanomaterial processing for gas sensors and related sensing applications. However, the major challenges in the field involve the choice of material for the sensing layer of the sensor device element, together with the right structure, assembly, and morphology through which the full sensing properties of the material can be realised. Herein, we critically review the hierarchical nanostructures of V₂O₅ nanomaterial for application in gas sensing technology. Beyond the sheet structure, which serves as the fundamental building block of the V₂O₅’smolecular arrangement, nanostructures ranging from nanobelts to nanowires, nanorods, nanoribbons, nanofibres, nanotubes, and thin films were discovered as preferred configurations and thermodynamically favourable structures, according to many synthesis processes. Ethanol (C₂H₅OH) and Nitrogen dioxide (NO₂) gases were identified as preferred molecules commonly detected by various V₂O₅ morphologies, with the nanotube structure showing preferential sensitivity and selectivity to C₂H₅OH. We also discuss perspectives from density functional theory (DFT) studies of V₂O₅ nanostructures and other (2D) materials structures for gas sensing applications. The studies highlight enhanced adsorption energy, increase conductivity, and band gap variation as a result of an upper shift in the Fermi level, all as a consequence of surface interaction between semiconductor crystal orientation and chemical molecules. Finally, our calculations of the optimised parameters for α-V₂O₅ orthorhombic structure showed good agreement with experimental and other theoretical data in the literature. The adsorption energy profile for NO₂ molecules revealed that the Ag-doped surface exhibits the most negative adsorption energy compared with the clean surface and other doped surfaces. Full article

Versatile nanostructured materials based on electrochemically etched porous silicon (pSi) are being developed, which have tuneable pore morphology and unique optical and electrochemical properties that enable their effective biosensing applications. It has been shown that fabrication parameters critically influence pore formation and sensor performance, yet challenges remain in reproducible synthesis, structural stability and device integration. Here we review the electrochemical etching synthesis of pSi and recent advances in pSi-based optical and electrochemical biosensors for detecting bacteria, biomolecules, and viruses. We highlight strategies such as surface functionalisation, incorporation of nanomaterials, and integration with microfluidic and lab-on-a-chip technologies that enhance sensitivity and response times by addressing mass transfer limitations. These developments highlight pSi’s potential as a low-cost, adaptable biosensing material with applications in clinical diagnostics and environmental monitoring, while mapping future directions to overcome current fabrication and stability challenges. Full article

Magnesium potassium phosphate cement (MKPC) exhibits rapid setting and high early strength, but its long-term performance is limited by microstructural heterogeneity and pore structure defects. These microstructural defects can increase pore connectivity and facilitate the ingress of aggressive agents, thereby limiting the long-term durability and service reliability of MKPC-based repair and protective materials. Nanomaterials have been applied to improve MKPC performance; however, the differences between conventional nano-SiO₂ (NS) and nano-Fe₂O₃ (NF), particularly their effects on hydration regulation and microstructure evolution, remain insufficiently understood. In this study, the effects of NF and NS incorporation on the hydration behavior, phase evolution, pore structure, and mechanical properties of MKPC were comparatively investigated. Orthogonal experiments, mechanical testing, calorimetry, XRD, FTIR, Raman mapping, SEM/EDS, MIP, and nanoindentation were employed to establish the relationship between nano-modification, microstructural evolution, and mechanical performance. The results provide a basis for selecting suitable nanomodifiers for MKPC-based materials used in rapid repair, protective applications, and other construction scenarios requiring rapid strength development and improved microstructural compactness. Compared with pure MKPC and previously reported NS-MKPC results, NF-MKPC showed higher strength development, refined pore structure, and improved micromechanical uniformity. The observed performance enhancement of NF-MKPC is consistent with accelerated early hydration, possible heterogeneous nucleation, pore refinement, and matrix densification. In comparison, NS-MKPC exhibited a different hydration and pore-evolution behavior under the investigated conditions. These findings indicate that NF and NS may regulate hydration and microstructure development differently in MKPC and provide guidance for selecting suitable nano-modifiers for high-performance phosphate cement materials. Under the investigated conditions, NF modification shows potential for MKPC applications requiring rapid strength development and improved microstructural compactness, such as rapid pavement repair, concrete surface repair, and protective coating applications. Full article

Metal–organic frameworks (MOFs) have significant potential in electrochemical sensors, but the guest molecules and residual solvents in the pores often block the active sites and limit the reaction kinetics. One-dimensional nanostructures can provide direct conduction pathways and shorten ion diffusion distances, thereby enhancing electron transport and electrode contact. Meanwhile, fluorine-incorporated MOF materials leverage the high electronegativity of fluorine to substitute oxygen, suppress oxidation to widen the voltage window, and improve stability through enhanced hydrophobicity. In this work, 4-fluorosalicylic acid (4FSA) was used as the ligand and benzimidazole (Bim) was introduced to adjust the coordination environment, and one-dimensional Bim4FSA-MOF nanorods were successfully constructed. While the guest molecules were largely removed, the nickel sites were thereby activated and the pore size was enlarged. Due to the synergistic effect of one-dimensional nanostructure-promoted electron transport and the Ni(OH)₂/NiOOH dynamic active center, the B-250 composite exhibited excellent performance in a glucose electrochemical sensor. The optimized sensor delivered a detection limit of 0.022 μM and a detection time of 0.9 s, along with a sensitivity value of 2986.45 μA mM⁻¹ cm⁻², which provides a new strategy for the design of efficient MOF-based electrochemical sensor interface. Full article

Soybean hulls, an abundant agro-industrial by-product, were valorized as a renewable cellulose source for nanocellulose production. Cellulose isolates were obtained by alkaline treatment followed by bleaching with sodium chlorite (NaClO₂) or hydrogen peroxide (H₂O₂) and subsequently used to produce cellulose nanocrystals (CNC) and TEMPO-oxidized cellulose nanofibrils (CNF). Process efficiency and the structural and rheological properties of the resulting nanocelluloses were systematically compared. Sodium chlorite bleaching removed lignin and hemicellulose more effectively than hydrogen peroxide treatment, yielding isolates with higher cellulose content. Consequently, CNC_NaClO2 exhibited greater aspect ratio, higher crystallinity, and improved network-forming ability. Their suspensions showed pronounced viscoelastic and thixotropic behavior (G′ > G″), whereas CNC_H2O2 displayed lower moduli and nearly Newtonian flow. CNF suspensions exhibited dominant elastic behavior and gel-like consistency regardless of bleaching method, although this effect was stronger for CNF_NaClO2 due to the formation of longer, more entangled fibrils. FTIR confirmed the high purity of all nanocelluloses, while negative surface charge ensured colloidal stability. Overall, bleaching chemistry governed nanocellulose morphology and rheological performance, enabling tailored functional properties. By maintaining a constant biomass source and identical nanostructure production conditions while varying exclusively the bleaching agent, this study implements a controlled-variable design that rigorously isolates the effect of bleaching treatment. This systematic comparative framework provides methodological robustness rarely achieved in previous studies, where differences in raw materials or processing conditions often confound interpretation. Full article

Severe steam channeling in heterogeneous heavy oil reservoirs severely restricts thermal recovery efficiency, as conventional conformance control materials cannot simultaneously achieve long-term high-temperature resistance and deep reservoir penetration. This work develops a high-temperature-resistant epoxy-based liquid microsphere system for deep profile control in heavy oil steam flooding. A triple thermal-stabilization strategy is constructed: imide chain extension to enhance backbone rigidity, benzoxazine-phthalonitrile grafting to form dense triazine crosslinked networks, and KH-550-functionalized nano-silica for synergistic reinforcement. FT-IR and ¹H NMR verify the successful incorporation of rigid imide and triazine structures. TGA confirms the optimal formulation exhibits less than 5% mass loss at 350 °C. Multi-segment sand-packed tube tests demonstrate favorable deep migration capacity with inter-stage pressure ratios below 4 across 5000–15,000 × 10⁻³ μm² permeability, and the cured network retains over 95% plugging efficiency after 350 °C steam scouring. Dual-tube heterogeneous flooding delivers 12.05% incremental oil recovery, outperforming rigid inorganic particles. This system provides a high-performance candidate for deep steam channeling mitigation in heavy oil thermal recovery. Full article

Ice accumulation severely threatens the safe operation of aerospace, wind power and power transmission facilities, while traditional deicing technologies suffer high energy consumption and secondary pollution. Bioinspired superhydrophobic photothermal coatings integrate micro-nano bionic architectures and light-to-heat conversion media to realize synergistic passive ice suppression and solar-driven active deicing, emerging as an eco-friendly anti-icing route. This critical review systematically sorts scattered experimental findings from existing literature and clarifies that most observed performance correlations are restricted by non-uniform test conditions, rather than universal mechanistic laws applicable to all service scenarios. All comparative observations between different photothermal material systems and biomimetic structures are derived from discrete experimental datasets without harmonized measurement frameworks, so definitive cross-group performance rankings cannot be generalized across all icing environments. This work classifies mainstream photothermal filler categories and corresponding microfabrication techniques, analyzes inter-study data discrepancies caused by the lack of unified ice characterization standards, and elaborates multi-dimensional practical limitations of lacquer-based anti-icing coatings, including weak mechanical robustness and heavy dependence on solar irradiation. Finally, we propose targeted breakthrough directions involving multi-mode energy synergy, computational structural optimization and standardized characterization protocols, to provide targeted mechanistic guidance for developing high-performance, industrially viable bionic anti-icing lacquers. Full article

Type 2 diabetes mellitus (T2DM) remains a global health crisis, with nearly 589 million adults currently affected and projections pointing toward 853 million by 2050. Despite an expanding pharmacological armamentarium, a significant proportion of patients fail to achieve adequate glycaemic control, and the limitations of existing therapies, including adverse effects, cost, and limited accessibility, underscore the compelling need for novel therapeutic approaches. Phytochemicals such as curcumin, berberine, quercetin, resveratrol, and epigallocatechin gallate possess well-documented antidiabetic activity, operating through the PI3K/Akt, AMPK (activated protein kinase), NF-κB/JNK (nuclear factor kappa-B), and GLP-1R (glucagon-like peptide-1) signalling axes to improve insulin sensitivity, suppress gluconeogenesis, protect pancreatic beta-cells, and attenuate chronic metabolic inflammation. However, their clinical utility has been fundamentally constrained by poor oral bioavailability arising from low aqueous solubility, gastrointestinal instability, extensive first-pass metabolism, and P-glycoprotein-mediated efflux. Advanced drug delivery systems, including liposomes, solid lipid nanoparticles (SLN), nanostructured lipid carriers, PLGA (Poly (lactic-co-glycolic acid)) and chitosan nanoparticles, nanoemulsions, self-nanoemulsifying drug delivery systems, and phytosomes have demonstrated the capacity to overcome these barriers, achieving five- to ten-fold improvements in systemic bioavailability and substantially enhanced antidiabetic efficacy in preclinical models. Emerging mechanistic evidence further positions gut microbiota modulation and epigenetic reprogramming as additional therapeutic axes through which nano-encapsulated phytochemicals may exert durable metabolic benefits. Nonetheless, critical translational challenges persist, encompassing nanotoxicological risks, herb–drug interactions, the absence of harmonised regulatory frameworks for nano-phytomedicine products, phytochemical raw material variability, and formidable technical and economic barriers to scalable nanoparticle manufacturing. This review synthesises the current mechanistic, formulation, and clinical evidence within a unified analytical framework and identifies the strategic priorities of rigorous clinical development, regulatory clarity, and manufacturing standardisation required to translate nano-phytomedicine science into evidence-based T2DM therapeutics. Full article

Commercial carbon-based electrodes such as graphite felt and carbon felt in all-vanadium redox flow batteries suffer from inherent drawbacks, including slow vanadium ion redox kinetics, insufficient intrinsic catalytic activity, fiber corrosion, and functional group loss under strong acidic oxidative conditions, significantly limiting battery energy efficiency and long-term operational reliability. Rare-earth elements, with their unique 4f electron shell structure, tunable electronic levels, abundant surface oxygen vacancy defects, and strong coordination ability, offer a dual pathway—electronic and microstructural modulation—to optimize the interfacial electrocatalytic behavior of carbon electrodes, providing a novel materials system to overcome electrode performance bottlenecks in vanadium batteries. This review systematically summarizes recent advances in rare-earth-functionalized carbon electrodes and electrocatalysts for vanadium redox flow batteries, elaborating on core modification strategies, performance enhancement trends, and synergistic catalytic mechanisms. It also presents quantitative experimental results from the literature to clearly demonstrate the benefits: CeO₂-modified graphite felt at 0.2 wt% shows a 10.8% increase in energy efficiency compared to pristine graphite felt at a current density of 200 mA·cm⁻², while multi-rare-earth co-doped carbon electrodes achieve a 65% reduction in charge transfer resistance relative to unmodified electrodes. The review systematically categorizes two dominant modification routes—surface nano-decoration with rare-earth oxides and lattice bulk doping with rare-earth elements—and summarizes design principles and enhancement mechanisms of diverse composite catalytic systems, including rare-earth–carbon nanocomposites, rare-earth-based heterojunctions, and porous rare-earth catalysts. It further analyzes critical challenges in current research, such as unclear long-term stability mechanisms, high costs of high-purity rare-earth raw materials, immature large-scale fabrication processes, and limited in situ dynamic characterization techniques. Compared with existing reviews, this work clearly distinguishes between surface loading and lattice doping as two distinct rare-earth modification approaches, clarifying their differences in active site formation, electronic regulation logic, and cycling stability. It establishes a comprehensive theoretical framework for the coupled electronic–geometric effects in rare-earth-modified carbon electrodes, linking the intrinsic physicochemical properties of rare earths, material microstructure design, and battery electrochemical performance. Moreover, it innovatively proposes a pathway toward full-lifecycle recycling and reuse of rare-earth-based catalytic electrodes for industrial implementation. This review provides a complete theoretical foundation for developing high-performance, long-cycle, low-cost vanadium redox flow battery electrode materials and supports their engineering scale-up, contributing to the development of large-scale, long-duration energy storage technologies. Full article