Search Results (766)

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

Herein, vinylbenzyl chloride (VBC)-grafted styrene-butadiene (SB) copolymers, with high contents of VBC (22–32 mol%), were synthesized and blended with low amounts (n = 3–10 wt%) of unfunctionalized poly(phenylene oxide) (PPO). Being well-known for its great chemical compatibility with polystyrene, PPO was selected as non-conductive, hydrophobic and mechanically robust component to be blended with graft copolymers in order to reduce their water uptake, thus improving their dimensional and mechanical stability after quaternization with trimethylamine. The resulting blend membranes were characterized in terms of thermal, mechanical, and ex situ electrochemical properties. Blend membranes generally presented improved mechanical properties, as well as reduced water uptake with respect to AEMs not containing PPO, while retaining ion conductivity values of 11.3–16.6 mS cm⁻¹, higher than that of a commercial hydrocarbon-based benchmark. Among the investigated blend AEMs, g-VBC-32/PPOn membranes were found to have the highest conductivity values (>15 mS cm⁻¹) and the best trade-off between water uptake, mechanical properties and hydrogen permeability. Overall, these results highlight pristine PPO blending as a cost-effective, simple and scalable route to improve the mechanical and dimensional stability of hydrocarbon-based AEMs. Full article

The Potiguar Basin, in Rio Grande do Norte (Northeastern Brazil), has an extensive coastline with a rich diversity of marine sponges that remain poorly explored for their biotechnological potential. In this study, three sponge species—Suberites aurantiacus, Mycale (Zygomycale) angulosa, and Halichondrida—were collected, and a preliminary extraction was then performed to remove the most hydrophobic fraction with n-hexane. The remaining sediment was re-extracted with chloroform and methanol (1:1), and the resulting extracts (ESUB, EMYC, and EHALI, respectively) were analyzed. Chemical characterization using Gas–Liquid Chromatography–Mass Spectrometry (GC/MS) revealed distinct profiles for each genus, with the presence of alcohols, alkaloids, phenolic compounds, and lipids, mainly sterols. ESUB presented 17 identified compounds, EMYC had 15 identified and EHALI showed 15 identified. The antioxidant potential of the extracts was evaluated in vitro using DPPH radical scavenging, copper ion chelation, and total antioxidant capacity (TAC). The EC₅₀ values (mg/mL) for DPPH were 0.05 (ESUB), 0.14 (EMYC), and 0.06 (EHALI), while for copper chelation they were 0.03, 0.034, and 0.026, respectively. Preliminary toxicological assays indicated low toxicity, with IC₅₀ values above 9.6 mg/mL in human erythrocytes and Tenebrio molitor larvae, demonstrating a favorable safety profile for potential therapeutic applications. The study presents a preliminary screening of underexplored species in an equally underexplored region and supports further studies on their bioactive potential. Full article

This paper reports the effects of formed perfluoroalkylsilane self-assembled monolayers (SAMs) on the tribological and corrosion properties of TiO_x-incorporated diamond-like carbon (TiO_x-DLC) coatings deposited on a Ti6Al4V substrate. The SAMs were formed using 1H,1H,2H,2H -perfluorodecyltrichlorosilane (FDTS) and (3,3,3 -trifluoropropyl) trichlorosilane (FPTS) compounds. Their presence was confirmed using techniques such as ellipsometry, time-of-flight secondary ion mass spectrometry, and Fourier-transform infrared spectroscopy. The results of the ball-on-disc test indicate the role of the structure of the created SAMs on their tribological properties. The FDTS compounds with longer alkyl chains favor the creation of a well-packed layer bonded to the TiO_x-DLC coating. This hydrophobic structure allows for obtaining the lowest coefficient of friction (0.180) during tribological tests. The results of electrochemical tests indicate that the SAM modification reduces the barrier properties of TiO_x-DLC and provides enhanced kinetic stability against carbon matrix oxidation at higher anodic potentials. Full article

Per- and polyfluoroalkyl substances (PFASs) are persistent contaminants that are widely detected in aquatic environments and are difficult to remove because of their stable carbon–fluorine bonds and amphiphilic structures. Metal–organic frameworks (MOFs), with high surface areas, tailorable porous frameworks, diverse metal nodes, and adjustable surface functionalities, provide promising platforms for PFAS adsorption. This review summarizes recent advances in the adsorptive removal of PFASs from water using MIL-, UiO-, ZIF-, and PCN-type MOFs and their derivatives. The effects of hydrophobic interface construction, amine functionalization, fluorination, defect engineering, thermal conversion, and pore regulation on adsorption performance were discussed. PFAS adsorption by MOFs is governed by multiple interactions, including electrostatic attraction, Lewis acid–base interactions, hydrophobic interactions, van der Waals forces, and hydrogen bonding. The impact of solution pH, coexisting ions, natural organic matter, PFAS molecular structures, and MOF structures was also reviewed. In addition, regeneration strategies and PFAS adsorption performance after regeneration were summarized. Despite the advances, challenges persist regarding MOF stability, regeneration, cost-effectiveness, and adsorption performance in real water matrices. Future research should therefore focus on sustainable material design and scalable development of MOF-based treatment systems for effective PFAS remediation. Full article

Organic electrochemical transistors (OECTs) utilize ion injections to regulate the overall conductivity of the organic semiconductor channel, achieving high transconductance (g_m) by coupling ionic and electronic charge carriers within the whole channel’s volume. However, the slow ion migration rate through the hydrophobic semiconducting polymer layer restricts the response rate of the device for widespread applications in biomedical sensing. This work introduced poly(ethylene glycol) (PEG) bisazide photo-crosslinking agent into the p-type semiconducting polymers as a hydrophilic active channel in accumulated-mode OECTs. Upon incorporation of PEG segments into conjugated polymers via photolithography, the resulting OECTs exhibit a significant enhancement in both µC* product and doping/de-doping dynamics by at least one order of magnitude. The photo-patterning of an ion-conducting semiconductor channel with a minimum line gap of 5 µm enables the fabrication of a depletion-mode inverter. This study presents a straightforward patterning process that enhances the hydrophilicity of various hydrophobic conjugated polymers while eliminating the need for complex synthesis procedures typically required for introducing ethylene glycol side chains on conjugated polymers. Full article

Reinforced concrete structures in marine environments are subjected to severe deterioration, particularly in tidal zones. The development of intrinsically hydrophobic concrete through internal modification provides a promising strategy to mitigate this challenge. This study employed sodium methyl silicate (SMS) as a hydrophobic agent to prepare recycled fine aggregate concrete (RFAC), which was subsequently subjected to accelerated indoor chloride dry–wet cycling. The deterioration behavior of RFAC and the degradation mechanism of the SMS-induced hydrophobic film during dry–wet cycling were investigated through evaluations of mechanical performance, hydrophobicity, chloride resistance, microstructure, phase composition, pore structure, chemical bonding, and functional groups. The results show that SMS improves the hydrophobicity of RFAC but inhibits its hydration process. The optimal SMS dosage for RFAC under dry–wet cycling is 9‰, which achieves a balance between hydrophobicity enhancement and pore structure optimization. Compared with ordinary RFAC, the specimen exhibits 12.9‰ and 17.6% increases in compressive strength and RDEM, respectively, after 30 cycles, accompanied by reductions of 25.8%, 52.7%, and 80.0% in peak free chloride content, chloride erosion depth, and convection zone depth, respectively. RFAC with 9‰ SMS exhibits a denser matrix with lower porosity and fewer corrosion products. SMS enhances chloride resistance mainly by reducing water transport and chloride ion ingress through hydrophobic modification. Dry–wet cycling gradually deteriorates the SMS-induced hydrophobic film through the weakening of Si-C-related structures, while the Si-O-Si framework remains relatively stable. A quantitative correlation between the contact angle and free chloride ion content is established, and the modified Lucas–Washburn equation provides a reasonable description of chloride ion penetration depth. Full article

As microplastics act as ubiquitous carriers for endocrine-disrupting additives in aquatic environments, understanding their leaching dynamics is of critical concern. This study systematically investigated the effects of ultraviolet (UV) aging on the release behavior of phthalates (di-n-butyl phthalate [DnBP] and di(2-ethylhexyl) phthalate [DEHP]) from polyvinyl chloride (PVC) microplastics across diverse environmental conditions, along with the underlying mechanisms. Kinetic analyses and experimental results indicated that the release of plasticizers under UV irradiation was driven by a dynamic competition between the photochemical stability of the plasticizers and the aging of the microplastics: the apparent cumulative amount of photolabile DnBP decreased as irradiation time increased. In contrast, the release of photoresistant DEHP significantly exceeded that under dark conditions in the later stages of aging. Furthermore, highly variable environmental factors exhibited significant selectivity in regulating the release: high ionic strength inhibited plasticizer release through salting-out and cationic bridging effects, with divalent ions (Mg²⁺) in particular suppressing DEHP release by up to 96%; conversely, dissolved humic acid caused a 13-fold surge in DEHP release via robust hydrophobic solubilization. Comprehensive multitechnique characterizations (including SEM, FTIR, XRD, and XPS) confirmed that UV-induced aging—encompassing intense dehydrochlorination reactions, a marked increase in polar oxygen-containing functional groups and the amorphization of crystalline regions—fundamentally dismantled the internal mass transfer resistance, thereby creating physical pathways for the outward migration of internal plasticizers. Ultimately, this study emphasizes that the synergistic interactions between material aging and complex hydrochemical conditions must be fully integrated into assessments of long-term ecological risks and predictions of the real-world environmental fate of microplastic-associated contaminants. Full article

The rapid development of implantable medical electronics requires robust biocompatible coatings capable of ensuring long-term stability in aggressive physiological environments. Although Grade 1 titanium is widely used for its excellent mechanical properties and corrosion resistance, active implants require defect-free insulating coatings to prevent electrical leakage and metal ion release. This study presents a systematic evaluation of Parylene C (P-C) thin films deposited by the Gorham chemical vapor deposition (CVD) process onto implant-grade titanium substrates. Four coating thicknesses (1, 5, 10, and 20 µm) were deposited and characterized using complementary chemical, morphological, optical, and mechanical techniques. Contact-angle measurements confirmed uniform hydrophobicity (90.56 ± 1.86°), while FTIR and EDX verified the characteristic chemical composition of P-C. Reflectometry, ellipsometry, and interferometry demonstrated excellent thickness control and deposition reproducibility. Pull-off testing showed high initial mechanical integrity, with detachment forces ranging from 52 to 73 N. However, accelerated PBS ageing (21 days at 90 °C) induced significant degradation, particularly for thicker coatings, reducing pull-off forces to 19–42 N. Likewise, thermal-shock cycling (−80 °C to +220 °C) caused severe interfacial damage, decreasing the required detachment force to approximately 5.5 N for 20 µm coatings because of extensive cracking and delamination. These results demonstrate that Parylene C provides excellent conformal coverage and chemical stability on titanium but that its durability is significantly affected by prolonged hydrothermal ageing and extreme thermal loading. This study provides practical guidelines for the design of reliable encapsulation systems for active implantable medical devices and highlights the need for improved interfacial engineering through optimized adhesion-promoting layers or hybrid protective architectures. Full article

To meet the mounting regulations on per- and poly-fluoroalkyl substances (PFAS) in drinking water, ion exchange (IX) has become one of the most widely used technologies. However, the effects of resin characteristics and effects of common water matrix ions (sulfate) on the competitive uptake of PFAS of varying chain lengths and functionalities in multicomponent systems are not well understood. In this study, two commercial strong-base IX resins were tested for competitive removal of 10 PFAS. This study demonstrates that polystyrene matrix (IRA900) IX significantly outperforms polyacrylic matrix (A860) IX in the removal of PFAS due to both electrostatic and hydrophobic interactions. More effective removal in IX was found in longer-chain PFAS and perfluoroalkyl sulfonic acids (PFSAs) than in perfluoroalkyl carboxylic acids (PFCAs). PFAS removal was effective over a broad pH range of 4–8.5 except for short-chain PFCAs, which were competed with hydroxide ions. The uptake of IRA900 decreased with the increase in sulfate concentration and the decrease was profoundly in shorter-chain PFAS. In kinetic tests, the PFAS removal for IRA900 was ~85% without sulfate and ~80% with sulfate within 48 h. Moreover, it was confirmed that the presence of sulfate suppressed shorter-chain PFAS and PFCA homologues. IRA900 was regenerated using NaCl, methanol (CH₃OH), and a combination. A decrease by 10.7–12.6% after first regeneration was attributed to PFCA. Full article

Ionic liquids (ILs) have attracted considerable scientific interest over nearly three decades, with thousands of studies highlighting their low volatility, thermal stability, and potential for property modification through cation and anion selection. However, their behavior under environmental conditions remains less clear, particularly when water, soil constituents, and competing ions are present. This article examines whether concepts developed for neat ILs can be directly transferred to aqueous and soil systems. Particular attention is given to ion pairing, dissociation, surfactant-like behavior, sorption, toxicity, and biodegradation. Evidence from studies on herbicidal ILs, conventional precursor salts, and their mixtures indicates that, under environmentally relevant conditions, cations and anions frequently behave as largely independent chemical species. Hydrophobic cations are often responsible for sorption and microbial toxicity, whereas herbicidal anions typically retain mobility and biodegradation patterns comparable to their conventional salt forms. These observations question the environmental significance of ion pairing and suggest that the extent to which IL properties can be controlled through cation and anion selection may be more limited than commonly assumed. Greater emphasis should therefore be placed on precise terminology, appropriate experimental controls, and validation under realistic environmental conditions when interpreting the behavior and environmental relevance of ILs. Full article

Rice glutelin hydrolysates (RGHs) with different degrees of hydrolysis (DH) were prepared using papain, and the structural characterization, physicochemical stability, and antioxidant activity of RGH were analyzed. Results showed that RGH primarily consisted of low molecular weight (MW) peptides (<3 kDa), with hydrophobic/aromatic amino acid content increasing with DH. Higher DH level led to reduced average particle size and zeta potential of RGH. Structurally, as DH increased, a decrease in α-helix content alongside increased β-sheet/random coil ratios was observed in RGH, indicating a transition towards a more disordered structure in RGH. Furthermore, the antioxidant activity of RGH was significantly enhanced with the increase in DH, with RGH-18 showing the highest bioactivity. RGH maintained stability and antioxidant capacity under gastrointestinal digestion as well as various environmental stresses, including varying pH and temperatures, and the presence of metal ions. Cellular experiments demonstrated that RGH-18 alleviated H₂O₂-induced oxidative damage in HepG2 cells, likely by inhibiting Keap1 and activating Nrf2 via the Keap1/Nrf2 pathway. This study supports the potential of RGH as a functional ingredient and provides insights for targeted rice peptide production. Full article

Copper–aluminum (Cu-Al) wire-bonded devices are widely used in microelectronic packaging; however, corrosion at exposed Cu-Al bimetallic interfaces can lead to Al pad degradation, undercutting, and eventual ball-bond lift-off or open-circuit failure under humid, halide-contaminated conditions. This work presents a scalable post-wire-bond wet-chemical passivation process using octadecylphosphonic acid (ODPA) to simultaneously modify exposed Cu/Pd-coated Cu (PCC) and Al surfaces. The passivation process includes a hydroxylation pretreatment to generate reactive oxide/hydroxide surface sites, followed by ODPA treatment and solvent rinsing to remove weakly adsorbed species. Surface modification was evaluated using contact-angle measurements, reflection–absorption infrared spectroscopy (RAIRS), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). ODPA treatment increased the water contact angle on Cu and Al, confirming a substantial increase in surface hydrophobicity following coating formation. RAIRS identified ODPA-associated aliphatic C-H bands, AFM showed treatment-induced nanoscale surface changes, and XPS supported metal–oxygen–phosphorus interfacial bonding. Under aggressive 100 ppm chloride-ion immersion, ODPA passivation strongly suppressed corrosion-induced ball-bond lift-off across both device platforms. Lift-off decreased from 99.0% to 0.73% for Cu-Al devices and from 23.3% to 0.42% for PCC-Al devices. Collectively, these findings establish an effective, process-compatible post-wire-bond strategy for substantially protecting corrosion-susceptible interfaces and thereby improving the reliability of wire-bonded interconnects in halide-containing environments. Full article

The stability of anthocyanins is a key factor limiting their use as functional natural colorants. This study evaluated the protective effect of zein on anthocyanins extracted from red corn (Zea mays) chaff, which is an underutilized agro-industrial byproduct. The extraction of anthocyanins was optimized using a Box–Behnken design, employing a 55.5% (v/v) aqueous ethanol solution at 45.21 °C and a solid-to-solvent ratio of 1.86 mg/mL (w/v). The resulting extract was rich in acylated anthocyanins derived from cyanidin, pelargonidin, and malvidin, which were identified using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (FIA-ESI-FTICR-MS). The interaction between zein and the anthocyanins was found to be thermodynamically spontaneous (indicated by a negative ΔG), endothermic (ΔH = 19.8 kJ mol⁻¹), and primarily driven by hydrophobic interactions (ΔS = 84.5 J mol⁻¹ K⁻¹). The addition of zein significantly decreased the degradation rate constant of the anthocyanins and increased their half-life, especially at pH 4 and storage temperatures of 4 °C and 20 °C. Moreover, the activation energy (E_a) for the zein–anthocyanin complex formation was lower (ranging from 63.64 to 47.75 kJ mol⁻¹) than that of the extract without zein (ranging from 59.36 to 74.71 kJ mol⁻¹), indicating that the zein complex has lower thermal sensitivity. Additionally, zein enhanced the red hues of the extract (increasing a* to 62.66) and preserved its antioxidant capacity, which even increased by up to 3.5 times under accelerated degradation conditions. Zein serves as an accessible and effective plant-based alternative for stabilizing anthocyanins in acidic environments, with potential applications in the development of functional natural colorants for the food industry. Full article

In order to solve the bottleneck problems of zinc anode in aqueous zinc-ion batteries, such as dendrite disorder growth, hydrogen evolution corrosion, and interface passivation, lard derivative coating (LDC) was fabricated on zinc anode using a coating–calcination process. The microstructure, surface physical, and chemical properties of LDC and its influence on zinc deposition behavior and interface stability were investigated using a combination of techniques, including scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The LDC-modified Zn anode (LDC@Zn) delivers stable cycling for over 3500 h at 1 mA·cm⁻²/0.5 mAh·cm⁻². In Zn||Cu asymmetric cells, an average coulombic efficiency of 99.8% is achieved over 2400 cycles, confirming highly reversible Zn plating/stripping behavior. Furthermore, the full cell maintains a reversible capacity of ~400 mAh·g⁻¹ after 800 cycles at 5 A·g⁻¹, demonstrating excellent rate capability and long-term stability. Overall, this work innovatively demonstrates that the LDC interphase integrates hydrophobic suppression of side reactions and zincophilic regulation of Zn²⁺ deposition within a single architecture, enabling a synergistic balance between interfacial stability and controlled ion transport, and providing a scalable strategy for stable Zn anodes and new insights into interfacial engineering. Full article