Long-term Stability Research Articles

Immobilization of Xylanase on ZnO nanoparticles obtained by green synthesis from Eupatorium cannabinum L. and its application in enrichment of fruit juices

Juice production is one of the main components of the nutritional food industry. Therefore, improving fruit juice quality and preventing the formation of negative by-products is important for human health. The role of environmentally friendly, safe and economically more affordable green nanocarriers in improving the quality of fruit juice is increasing day by day. For this purpose, zinc oxide nanoparticles (ZnONPs) were prepared from the aqueous extract of the Eupatorium cannabinum L. using the green synthesis method. After immobilization, structural and morphological characterizations of the prepared ZnONPs and xylanase (Xyl)@ZnONPs were carried out, which confirmed that both the synthesis of ZnONPs and the immobilization of Xyl enzyme on ZnONPs were successfully carried out. The biochemical parameters of Xyl@ZnONPs such as optimum pH and temperature, kinetic parameters, thermal stability, reusability, and storage stability were investigated and compared with free Xyl. After immobilization, the optimum pH of free Xyl shifted from 5.0 to an alkaline pH of 8.0, while no change in the optimum temperature (70 °C) was observed for both enzymes. While the activation energy of free Xyl was 5.56 kJ/mol, it was found to be 7.27 kJ/mol for Xyl@ZnONPs. Xyl@ZnONPs outperformed free Xyl due to its long-term storage stability and reusability. Moreover, Xyl@ZnONPs retained 50 % of its activity after 5 reuses and 87 % of its activity after 4 weeks of storage at room temperature. In addition, a decrease in Km value and an increase in Vmax value were observed after immobilization, which means the increased catalytic activity of the Xyl@ZnONPs. As a result of re-using Xyl@ZnONPs in orange juice for 6 cycles, clarification yield of 66.43 % was obtained under optimized conditions. Overall, this study prepared a suitable, environmentally friendly, and robust carrier support for Xyl immobilization and developed a biocatalyst that will provide high performance in the industrial field.

Neuronal functional connectivity is impaired in a layer dependent manner near chronically implanted intracortical microelectrodes in C57BL6 wildtype mice

Objective. This study aims to reveal longitudinal changes in functional network connectivity within and across different brain structures near chronically implanted microelectrodes. While it is well established that the foreign-body response (FBR) contributes to the gradual decline of the signals recorded from brain implants over time, how the FBR affects the functional stability of neural circuits near implanted brain–computer interfaces (BCIs) remains unknown. This research aims to illuminate how the chronic FBR can alter local neural circuit function and the implications for BCI decoders. Approach. This study utilized single-shank, 16-channel,100 µm site-spacing Michigan-style microelectrodes (3 mm length, 703 µm2 site area) that span all cortical layers and the hippocampal CA1 region. Sex balanced C57BL6 wildtype mice (11–13 weeks old) received perpendicularly implanted microelectrode in left primary visual cortex. Electrophysiological recordings were performed during both spontaneous activity and visual sensory stimulation. Alterations in neuronal activity near the microelectrode were tested assessing cross-frequency synchronization of local field potential (LFP) and spike entrainment to LFP oscillatory activity throughout 16 weeks after microelectrode implantation. Main results. The study found that cortical layer 4, the input-receiving layer, maintained activity over the implantation time. However, layers 2/3 rapidly experienced severe impairment, leading to a loss of proper intralaminar connectivity in the downstream output layers 5/6. Furthermore, the impairment of interlaminar connectivity near the microelectrode was unidirectional, showing decreased connectivity from Layers 2/3 to Layers 5/6 but not the reverse direction. In the hippocampus, CA1 neurons gradually became unable to properly entrain to the surrounding LFP oscillations. Significance. This study provides a detailed characterization of network connectivity dysfunction over long-term microelectrode implantation periods. This new knowledge could contribute to the development of targeted therapeutic strategies aimed at improving the health of the tissue surrounding brain implants and potentially inform engineering of adaptive decoders as the FBR progresses. Our study’s understanding of the dynamic changes in the functional network over time opens the door to developing interventions for improving the long-term stability and performance of intracortical microelectrodes.

Highly sensitive detection of n-butanol based on In2O3/SnO2 composite hierarchical microspheres

Constructing heterojunction composites is an effective method to enhance the gas-sensing performance of metal oxide semiconductors. In this paper, In2O3 hierarchical microspheres were hydrothermally fabricated, and they were coated with SnO2 nanoparticles by a liquid phase deposition method to improve the sensor response to n-butanol. The impact of deposition time on the morphology, structure and gas sensing performance were investigated. The results indicated that the In2O3/SnO2 composite hierarchical microspheres with a deposition time of 60 min possessed the largest specific surface area of 137.6 m2/g and the best gas sensing properties. Its response toward 20 ppm n-butanol gas at 140 °C was 359, which was much higher than that of pure In2O3 hierarchical microspheres (the response was 51 to 100 ppm n-butanol gas at 140 °C). In addition to enhanced sensitivity, this sensor showed quick recovery time, excellent selectivity, repeatability, and long-term stability for n-butanol, indicating its potential for practical applications.

Improving the sensing performance of SnWO4 nanostructure at room temperature based on CsPbBr3 composite

The accurate detection of hazardous gases and monitoring of ambient temperature are crucial for preserving the ecological environment, safeguarding human health, and fostering industrial advancement. In this research, a straightforward hydrothermal technique was employed to synthesize the heterogeneous nanocomposite structure of CsPbBr3/SnWO4, which facilitates the detection of ethanolamine gas at room temperature. The synthesized CsPbBr3/SnWO4 heterostructures underwent further analysis using XRD, SEM, HRTEM, XPS, BET and Mott-Schottky techniques. The findings revealed that the CsPbBr3/SnWO4 heterostructure exhibits a coarse cubic morphology, consisting of nano-cubic CsPbBr3 and nano-sheet SnWO4. Additionally, the integration of CsPbBr3 markedly enhances the specific surface area of the pristine SnWO4 nanosheets. Due to its coarse surface, expansive contact area, and n-n heterojunction, CsPbBr3–SnWO4 demonstrates remarkable selectivity, superior long-term stability, and a sensitivity of 45.6 to ethanolamine at ambient temperature. In conclusion, the CsPbBr3/SnWO4 heterostructure, constructed from a cube with a rough surface, is anticipated to serve as an effective room temperature sensor with heightened selectivity for ethanolamine.

Multi-center study of use of the Exeter stem in Japan: a 10-year follow-up report.

Since the introduction of the Exeter stem for clinical use in Japan in 1996, the number of stems used has continued to rise owing to its favorable results. We investigated the outcomes of patients who had previously undergone total hip arthroplasty with the Exeter stem in Japan with a 10-year + follow-up period. This retrospective cohort study used clinical and radiographic data of 682 cases of primary total hip arthroplasty performed using the Exeter stem. The mean postoperative follow-up period was 13.3years. Femoral-side revision was required in 14 hips, with no cases of aseptic stem loosening-associated revision observed. Kaplan-Meier survival analysis predicted 97.3% 15-year survival when revision for any reason was used as the endpoint. The obtained findings suggested the excellent long-term stability of the Exeter stem for primary total hip arthroplasty in Japan.

Low-cost iron (Fe) hollow fiber membrane for hydrogen separation

Dense metal membranes are widely studied due to their promising performance in hydrogen separation. In this work, the low-cost dense iron (Fe) hollow fiber membranes (FeHFMs) were developed via the phase inversion and high-temperature sintering method. By tuning the preparation conditions, two typical gas-tight hollow fibers referred to as the sandwich- and honeycomb-structured membranes were successfully synthesized. H2 permeation behavior was well described by Sieverts equation based on the solution-diffusion mechanism. The sandwich-structured FeHFMs had an H2 flux of up to 7.51 mmol m−2 s−1 when operated at a temperature of 850 °C. In comparison, the honeycomb-structured FeHFMs further enhanced the H2 flux by a factor of 3.2 due to the optimized membrane morphology with only one single dense iron layer. The developed FeHFMs showed superior H2 permeation stability in thermal shock tests (40 h) and long-term stability tests (120 h). This work also expanded the potential application horizons of the FeHFMs, which can be easily tailored into porous or dense structures by tuning the sintering conditions.

Interfacial DominoEffect Triggered by β-alanine Cations Realized Highly Reversible Zinc-Metal Anodes.

Realizing durative dense, dendrite-free, and no by-product deposition configuration on Zn anodes is crucial to solving the short circuit and premature failure of batteries, which is simultaneously determined by the Zn interface chemistry, electro-reduction kinetics, mass transfer process, and their interaction. Herein, this work unmasks a domino effect of the β-alanine cations (Ala+) within the hydrogel matrix, which effectively triggers the subsequent electrostatic shielding and beneficial knock-on effects via the specifical adsorption earliest event on the Zn anode surface. The electrostatic shielding effect regulates the crystallographic energetic preference of Zn deposits and retards fast electro-reduction kinetics, thereby steering stacked stockier block morphology and realizing crystallographic optimization. Meanwhile, the mass transfer rate of Zn2+ ions was accelerated via the SO42- anion immobilized caused by Ala+ in bulk electrolyte, finally bringing the balance between electroreduction kinetics and mass transfer process, which enables dendrite-free Zn deposition behavior. Concomitantly, the interfacial adsorbed Ala+ cations facilitate the electrochemical reduction of interfacial SO42- anions to form the inorganic-organic hybrid solid electrolyte interphase layer. The above domino effects immensely improve the utilization efficiency of Zn anodes and long-term stability, as demonstrated by the 12 times longer life of Zn||Zn cells (3650 h) and ultrahigh Coulombic efficiency (99.4%).

Raspberry-liked Pickering emulsions based inulin microparticles for enhanced antibacterial performance of essential oils

Pickering emulsions seem to be an effective strategy for encapsulation and stabilization of essential oils. In this work, a novel raspberry-liked Pickering emulsion (RPE) loading Mosla chinensis ‘Jiangxiangru’ essential oil (MJO) was successfully engineered by using ethyl lauroyl arginate (ELA) decorated nanosilica (ELA-NS) as particles emulsifier. And the ELA-NS-stabilized MJO Pickering emulsion (MJO-RPE) was further prepared into inulin-based microparticles (MJO-RPE-IMP) by spray-drying, using inulin as matrix formers. The concentration of ELA-NS could affect the formation and stabilization of MJO-RPE, and the colloidal behavior of ELA-NS could be modulated at the interfaces with concentration of ELA, thus providing unique role on stabilization of MJO-RPE. The results indicated that the MJO-RPE stabilized ELA-NS with 2 % NS modified by 0.1 % ELA had long-term stability. MJO-RPE exhibited a raspberry-liked morphology on the surface, attributed to ELA-NS covered in the droplet surface. The inulin-based matrix formers could effectively prevent MJO-RPE from agglomeration or destruction during spray-drying, and 100 % concentration of inulin based microparticles formed large composite particles with high loading capacity (98.54 ± 1.11 %) and exhibited superior thermal stability and redispersibility of MJO-RPE. The MJO-RPE exhibited strong antibacterial efficacy against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Pseudomonas aeruginosa (P. aeruginosa), owing to the adhesion to bacterial membrane dependent on the raspberry-liked surface of MJO-RPE, whose minimum inhibitory concentration (MIC) of the above three bacteria were (0.3, 0.45, and 1.2 μL/mL), respectively, lower than those (0.45, 0.6 and 1.2 μL/mL) of MJO. Therefore, the Pickering emulsion composite microparticles seemed to be a promising strategy for enhancing the stability and antibacterial activity of MJO.

Lithium Borate Polycarbonates for High-Capacity Solid-State Composite Cathodes.

Improving composite cathode function is key to the success of the solid-state battery. Maximizing attainable cathode capacity and retention requires integrating suitable polymeric binders that retain a sufficiently high ionic conductivity and long-term chemo-mechanical stability of the cathode active material-solid-electrolyte-carbon mixture. Herein, we report block copolymer networks composed of lithium borate polycarbonates and poly(ethylene oxide) that improved the capacity (200 mA h g-1 at 1.75 mA cm-2) and capacity retention (94% over 300 cycles) of all-solid-state composite cathodes with nickel-rich LiNi0.8Co0.1Mn0.1O2 cathode active material, Li6PS5Cl solid electrolyte, and carbon. Tetrahedral B(OR)2(OH)2- anions immobilized on the polycarbonate segments provide hydrogen-bonding chain crosslinking and selective Li-counterion conductivity, parameterized by Li-ion transference numbers close to unity (tLi+ ~ 0.94). With 90 wt% polycarbonate content and a flexible low glass transition temperature backbone, the single-ion conductors achieved high Li-ion conductivities of 0.2 mS cm-1 at 30°C. The work should inform future binder design for improving the processability of cathode composites towards commercialising solid-state batteries, and allow use in other cell configurations, such as lithium-sulphur cathode designs.

Residual Echo State Networks: Residual recurrent neural networks with stable dynamics and fast learning

Residual connections have been established as a staple for modern deep learning architectures. Most of their applications are cast towards feedforward computing. In this paper, we study the architectural bias of residual connections in the context of recurrent neural networks (RNNs), specifically in the temporal dimension. We frame our discussion from the perspective of Reservoir Computing and dynamical system theory, focusing on important aspects of neural computation like memory capacity, long-term information processing, stability, and nonlinear computation capability. Experiments corroborate the striking advantage brought by temporal residual connections for a plethora of different time series processing tasks, comprehending memory-based, forecasting, and classification problems.

Novel intelligent packaging films based on starch/PVA with Cu-ICA nanocrystal as functional compatibilizer for monitoring food freshness

Considering public health and environmental safety, the development of reliable and efficient monitoring methods is essential to ensure food quality and safety. Herein, a new Cu-based metal organic framework (Cu-ICA) nanocrystal with ammonia-sensitive performance was built up and then introduced as a functional compatibilizer of starch/polyvinyl alcohol (STA/PVA) blend to develop high-performance intelligent packaging films for food freshness monitoring. The introduction of Cu-ICA upgraded the compatibility, mechanical strength (42.9 MPa), UV-protection (with UV transmittance of only 2.8 %), and moisture/oxygen barrier performances of STA/PVA film. Furthermore, the developed STA/PVA/Cu-ICA films presented long-term colour stability, outstanding antibacterial efficacy (over 99.5 %) toward both Escherichia coli and Staphylococcus aureus bacteria, as well as remarkable ammonia-sensitive discoloration capability. The STA/PVA/Cu-ICA films possessed visually identifiable colour change during the monitoring of shrimp spoilage. These findings indicate that the developed STA/PVA/Cu-ICA film possesses tremendous potential as an intelligent active packaging material.

Mn-Ag bimetals supported on plate-like ZSM-5 as efficient and stable catalysts for the catalytic combustion of toluene: Synergistic effects and catalytic mechanisms

Ag-modified MnO2 loaded on plate-like ZSM-5 (PZ5) with different Ag/Mn ratios were synthesized by an in-situ growth method and used as catalysts for toluene combustion, as a probe molecule of volatile organic compounds (VOCs). The results showed that Ag doping greatly enhanced the toluene combustion activity (Mn50Agy/PZ5). Among them, Mn50Ag0.04/PZ5 showed the highest catalytic activity for toluene combustion with 90 % conversion of toluene at 234 °C (T90), and the reaction rate calculated per unit mass of Mn was 1.22×10−7 at 220 °C, which was 2.7 times higher than that of MnO2. In addition, Mn50Ag0.04/PZ5 exhibited excellent long-term stability and water resistance. Various characterizations indicated that the excellent performance of Mn50Ag0.04/PZ5 was attributed to its higher Mn2++Mn3+/Mn4+ ratios, higher reducibility, and more active surface adsorbed oxygen species. Finally, in-situ DRIFTS studies confirmed that Ag doping did not alter the catalytic combustion pathway of toluene over the Mn50Ag0.04/PZ5 catalyst but could accelerate the rate of conversion of toluene to the final products because the transfer of electrons from Ag+ to lattice oxygen persuaded the weaken of the Mn-O bond, and then made it easier for bulk lattice oxygen to migrate towards the Ag-MnO2 interface or catalysts’ surface, thus showing the better catalytic performance for toluene combustion.

Enhanced electrochemical detection of chikungunya virus through aptasensor modification with origami paper-based ternary nanocomposite

Electrochemical sensors have drawn significant attention due to their crucial significance in the early detection of infectious illnesses, signifying their critical importance in diagnostic applications. This study’s proposed novel aptasensor exhibits a distinctive origami-based ePAD design, utilizing a unique silver-gold and zinc oxide (Ag-Au-ZnO) ternary nanocomposite for enhanced charge-transfer properties. Composite nanomaterials have a lower toxicity level, a higher signal enhancement capacity, increased sensitivity, improved conductivity, superior solubility, enhanced resolution capabilities, and a more straightforward functionalization process than individual nanomaterials. Employing paper, an economically advantageous substrate amenable to large-scale production with an origami-based ePAD is a critical enhancement of the sensor’s commendable attributes. Categorized as precision tools with an eco-conscious design, these sensors stand out for their streamlined manufacturing of environmentally sensitive substrates. This research capitalizes on the inherent foldability of paper to construct a three-dimensional multi-angular aptasensor, demonstrating cutting-edge specificity for chikungunya virus (CHIKV) detection. X- ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), UV–vis spectroscopy, and Fourier transmission infrared spectroscopy (FTIR) characterized the nanocomposites. This study also includes aptamers as outstanding and sensitive instruments for quick diagnostic applications. With the use of Cyclic Voltammetry (CV), the analytical response of the aptasensor was carefully evaluated. The study demonstrates a broad linear detection range spanning from 1 ng/ml to 10 µg/ml, with an impressively low limit of detection (LOD) at 1 ng/ml for the CHIKV antigen (CHIKV-Ag), underscoring the novelty and heightened sensitivity of this aptasensor design. Moreover, the aptasensor successfully detects CHIKV antigens in serum samples, and a long stability test demonstrates its practical utility and long-term stability for clinical applications. The proposed study concludes by introducing a novel origami-based paper-based analytical device (ePAD) as a promising tool for the quick, precise, and selective identification of the CHIKV antigen as well as its affordability, easy fabrication, and suitability of POCT testing makes an excellent diagnosing technique in resource-limited settings.

Tailored design of NHS–SS–NHS cross-linked chitosan nano-hydrogels for enhanced anti-tumor efficacy by GSH-responsive drug release

The traditional chemotherapeutic agents’ disadvantages such as high toxicity, untargeting and poor water solubility lead to disappointing chemotherapy effects, which restricts its clinical application. In this work, novel size-appropriate and glutathione (GSH)-responsive nano-hydrogels were successfully prepared via the active ester method between chitosan (containing –NH2) and cross-linker (containing NHS). Especially, the cross-linker was elaborately designed to possess a disulfide linkage (SS) as well as two terminal NHS groups, namely NHS–SS–NHS. These functionalities endowed chitosan-based cross-linked scaffolds with capabilities for drug loading and delivery, as well as a GSH-responsive mechanism for drug release. The prepared nano-hydrogels demonstrated excellent performance applicable morphology, excellent drug loading efficiency (∼22.5%), suitable size (∼100 nm) and long-term stability. The prepared nano-hydrogels released over 80% doxorubicin (DOX) after incubation in 10 mM GSH while a minimal DOX release less than 25% was tested in normal physiological buffer (pH = 7.4). The unloaded nano-hydrogels did not show any apparent cytotoxicity to A 549 cells. In contrast, DOX-loaded nano-hydrogels exhibited marked anti-tumor activity against A 549 cells, especially in high GSH environment. Finally, through fluorescent imaging and flow cytometry analysis, fluorescein isothiocyanate-labeled nano-hydrogels show obvious specific binding to the GSH high-expressing A549 cells and nonspecific binding to the GSH low-expressing A549 cells. Therefore, with this cross-linking approach, our present finding suggests that cross-linked chitosan nano-hydrogel drug carrier improves the anti-tumor effect of the A 549 cells and may serve as a potential injectable delivery carrier.

Mitigating Medication Tampering and Diversion via Real-time Intravenous Opioid Quantification.

Opioid tampering and diversion pose a serious problem for hospital patients with potentially life-threatening consequences. The ongoing opioid crisis has resulted in medications used for pain management and anesthesia, such as fentanyl and morphine, being stolen, substituted with a different substance, and abused. This work aims to mitigate tampering and diversion through analytical verification of the administered drug before it enters the patient. We present an electrochemical-based sensor and miniaturized wireless potentiostat that enable real-time intravenous (IV) monitoring of opioids, specifically fentanyl and morphine. The proposed system is connected to an IV drip system during surgery or post-operation recovery. Measurement results of two opioids are presented, including calibration curves and data on the sensor performance concerning pH, temperature, interference, reproducibility, and long-term stability. Finally, we demonstrate real-time fluidic measurements connected to a flow cell to simulate IV administration and a blind study classified using a machine-learning algorithm. The system achieves limits of detection (LODs) of 1.26 μg/mL and 2.75 μg/mL for fentanyl and morphine, respectively, while operating with >1-month battery lifetime due to an optimized ultra-low power 36 μA sleep mode.

Is Polyetheretherketone an Effective Alloplastic Material in Comparison to Titanium in Calvarial Reconstruction.

Polyetheretherketone (PEEK) and titanium (Ti) cranioplasty implants ideal outcomes are good esthetics, long-term stability, and protection of the fragile brain tissue. However, it is unclear whether PEEK implants can offer an equal alternative to Ti implants. This work aimed to critically review papers and case series published on both Ti and PEEK Cranioplasty regarding complications, clinical outcomes, ease of use, esthetics, manufacture and availability, cost and time-saving factors, postoperative quality of life (QOL), as well as their suitability for the fronto-orbito region reconstruction. PubMed database was sourced for published literature in the period 2007 to the end of 2023; a further manual search for articles was carried out on the reference lists of each paper. A total of 48980 papers were found during the initial search, but only 33 articles met the inclusion criteria. A total of 6023 cranial implants, with 3879 being Ti and 1205 PEEK. Titanium was the material of choice in over 64.4% of cases; however, Ti has been in application for many years compared to PEEK. Out of the 33 papers, there was 27 retrospective cohort/analysis/case series and reviews: 1 meta-analysis, 2 systematic reviews and 3 randomized control trials. Four articles commented on the QOL, 15 on esthetics, 7 discussed cost and time-saving without measurable variables, and 7 articles looked explicitly at the complex fronto-orbito region, of which 49% were primary 1-stage surgical reconstructions, 54% were reconstructed with PEEK and 7% Ti (CAD/CAM). There is no absolute consensus for the preference of either material, however, in the fronto-orbito region, PEEK is the material of choice for ease of use, esthetics, and time-saving. However, there are no long-term studies on PEEK cranioplasty, and fewer in comparison with Ti implants. Further research is required in this field. No reliable or measurable data was found to determine the QOL, esthetics, cost, or time-saving elements.

Platinum-nickel nanocrystals anchored on heteroatom-functionalized Ti3-xC2Ty MXene 3D porous architecture for electrocatalytic hydrogen evolution in alkaline electrolytes

BackgroundRational design and construction of efficient electrocatalysts are crucial for enhancing the activity and stability of the hydrogen evolution reaction (HER) in alkaline electrolytes. MethodsHerein, heteroatom (phosphorus and sulfur)-functionalized and self-adapting Ti3+ species defect decorated Ti3-xC2Ty MXene (PS-TCT) with 3D porous architecture for anchoring platinum-nickel (PtNi) bimetallic nanocrystals for alkaline electrocatalytic HER. Experimental and theoretical studies have shown that the heteroatoms delicately modulated the electronic configuration of MXene to optimize the adsorption capacity of the reaction intermediates. The 3D porous spatial configuration of PS-TCT with abundant Ti3+ species defect endowed an efficient channel for charge transfer and sufficient catalytically active sites, thus facilitating fast dynamics and long-term stability. Additionally, the strong bimetal-substrate interfacial interaction (Pt-S bonding) between PtNi and PS-TCT established an electron directional transport channel, thus achieving valid and stable interfacial electron transport. Significant findingsConsequently, the optimized PtNi@PS-TCT nanohybrids showed remarkable catalytic activity with low overpotentials of 56.1 mV at 10 mA cm−2 and impressive Tafel slope of 81 mV dec−1 for HER in alkaline electrolytes (1.0 M KOH), while exhibiting outstanding electrochemical stability. This work offers a constructive route for precisely constructing high-performance multifunctional composite electrocatalysts.

Hydrogen and NH3 co-adsorption on Pd–Ag membranes

Ammonia (NH3) represents a carbon-free hydrogen carrier that can be used as a zero-emission fuel in the maritime and heavy transport sector with hydrogen fuel cells. To use ammonia as feedstock, the hydrogen must be recovered through NH3 decomposition into H2 and N2. Ammonia decomposition by a membrane-enhanced reactor would inherently produce high-purity H2 through the membrane avoiding the need for a costly hydrogen separation/purification unit. Pd-based membrane reactors can obtain full ammonia decomposition and show significantly higher conversion than conventional reactors. However, the H2 permeability is found to be inhibited in the presence of NH3. A further fundamental understanding of the long-term stability and performance of the Pd-based membranes under exposure to NH3 is therefore required. In the current work, the adsorbate-adsorbate interactions during co-adsorption, the influence the presence of NH3 has on the hydrogen dissociation kinetics, and surface segregation effects in the presence of NH3 and/or hydrogen on the surface of Pd and Pd3Ag are investigated in detail using density functional theory calculations. We find that both the hydrogen surface coverage and dissociation kinetics are hindered by the presence of NH3 on the surface, and possible segregation of Ag towards the surface in the presence of NH3, which could explain the reduced hydrogen permeation in NH3.

Au nanoparticles decorated ZnIn2S4/WO3 core-shell heterostructures as highly sensitive and selective ethylene glycol gas sensors

Ethylene glycol (EG) is extensively utilized as anti-freezer and deicer, which would bring potential health risk under unintentional exposures especially with hazardous inhalation of EG aerosols or vapors. In this study, ZnIn2S4 (ZIS)/WO3 core-shell nanofibrous heterostructure loaded with optimized Au nanoparticles (NPs) was prepared for superiorly sensitive and selective EG gas sensing. The ternary Au/ZIS/WO3 heterostructures exhibited an excellent response (Ra/Rg=98.92) to 50 ppm EG, demonstrating an enhancement of 3.5 times compared to the binary ZIS/WO3, and a substantial improvement of 59.5 and 24.1 times compared to pure WO3 and ZIS, respectively. The ternary Au/ZIS/WO3 heterostructures also possessed an extremely low detection limit of 6 ppb, as well as excellent selectivity, repeatability, and long-term stability. This exceptional gas sensing performance can be attributed to its distinctive ternary Au/ZIS/WO3 heterostructures with high specific surface areas. This unique structure not only facilitate the activation of abundant active oxygen species, but also promote the spillover effect of Au and enhance effective electronic distribution, thereby providing more EG adsorption sites, which was confirmed by density functional theory calculation. The synergistic effect arising from the metal-semiconductor interface and the core-shell heterostructure presents a novel avenue for advancing high-performance sensor technologies.

Enhancing Hydrogels with Quantum Dots

This manuscript explores the interdisciplinary integration of quantum dot–hydrogel composites and smart materials and their applications across a spectrum of fields, including biomedical engineering, environmental sensing, and energy harvesting. It covers the synthesis of novel materials like fluorescent hydrogel nanocomposites that display enhanced chemical stability, mechanical strength, and thermal resistance, highlighting their utility in environmental monitoring and catalysis. In the biomedical sector, innovations include hydrogel composites for targeted drug delivery and advanced therapies such as photothermal DNA hydrogels for tumor treatment. This review also discusses the application of these materials in imaging, diagnostics, and the development of smart sensors capable of detecting various biological and environmental changes. Its scope further extends to optoelectronics and the design of energy-efficient systems, underscoring the versatile functionalities of hydrogels in modern technological applications. Challenges remain in scaling up these technologies for commercial use and ensuring their long-term stability and safety, necessitating future research focused on sustainable, scalable solutions that can be integrated into existing systems.