Mesoporous Oxide Research Articles

Design, synthesis, antibacterial evaluation, and molecular docking studies of diethyl((substituted phenyl)((4-(N-(5-methyl-4,5-dihydroisoxazol-3-yl)sulfamoyl)phenyl) amino)methyl)phosphonates

An efficient green synthesis of diethyl((substituted phenyl)((4-(N-(5-methyl-4,5-dihydroisoxazol-3-yl)sulfamoyl)phenyl) amino)methyl)phosphonates was accomplished by the condensation of 4-amino-N-(5-methyl-4,5-dihydroisoxazol-3yl) benzenesulfonamide with various aldehydes and diethyl phosphite using mesoporous titania-ceria mixed oxide (MTCMO) as a nanocatalyst under microwave irradiation and solvent-free conditions. Antimicrobial activity was performed for the synthesized compounds and the compounds 4a, 4c, 4d, 4e and 4f exhibited highest inhibitory activity against Escherichia coli using Penicillin and Tetracycline as standards. In addition, molecular docking studies were also carried out against Cox-2 with Celocoxib as the standard.

Design of Ru-Co/MgO-Al2O3 catalyst system for CO2 reforming of methane: Performance investigation concerning the Mg/Al ratio

This study explores the design of bimetallic Co-Ru nanoclusters deposited on surface-tuned mesoporous Mg-Al mixed oxide support for the CO2 reforming of methane (DRM) process. The evaporation-induced self-assembly technique was used to create a series of MgO-Al2O3 mixed oxide supports with various Mg/Al molar ratios. Co and Ru nanoclusters over the MgO-Al2O3 supports were decorated using a urea precipitation-deposition approach. Results revealed that the activity and stability of the DRM catalyst were substantially reliant on the Mg/Al molar ratio and Co-Ru metal combination. Among the series of Co-loaded catalysts, the best performance was obtained over an unpromoted CoMg20Al catalyst (20 wt.% Mg), with only a 10 % activity loss after 50 h of study. A modification of CoMg20Al by 0.5 wt.% Ru significantly enhanced the catalytic activity, demonstrating a 93 % methane conversion with raw feed and stable activity over a 100-h extended activity analysis. The catalyst characterization showed that Mg concentration increased basic sites over Mg-Al support. Due to the separation of crystalline phases as MgO-MgAl2O4, CoMg40Al had the most basic sites but poor DRM reaction performance. Balanced acidic/basic properties and well-dispersed Co-Rh nanoclusters-maintained DRM activity and stability. Ru-promoted CoMg20Al catalyzed the lowest activation energies.

Preparation and Optimization of Mesoporous SnO2 Quantum Dot Thin Film Gas Sensors for H2S Detection Using XGBoost Parameter Importance Analysis

Tin oxide (SnO2) is a traditional gas-sensitive semiconductor with excellent response to various gases. However, its sensor performances are attenuated by the utility factor during gas diffusion in the sensing body. Therefore, the rational design of microstructure of devices is attractive and necessary because it may provide a sensible and controllable microstructure, which facilitates gas diffusion and inhibits the utility factor. Herein, the mesoporous tin oxide (MPTD) quantum dot thin film for H2S gas sensors is prepared by a facile route, which creates a mesoporous microstructure for thin films by the thermal decomposition of NH4Cl. The pore size of the thin films is controlled to be 19.36–40.13 nm. The mesoporous microstructure exhibits enhanced gas-sensing properties amounting to a 30-fold increase in response and 1/3 reduction in recovery time in H2S detection at room temperature (25 °C), with a limit of detection of 0.4 ppm. To determine the importance of sensor parameters such as pore size, film thickness, and grain size, an eXtreme Gradient Boosting (XGBoost) algorithm model was developed to examine the feature importance of each parameter on the gas-sensing performance of the MPTD sensors. The visual illustration of parameter importance is revealed to facilitate the optimization of technical preparation parameters as well as the rational design of semiconductor gas sensors.

Plasmonic inhibition of bacterial adhesion on gold-decorated mesoporous zirconium oxide thin films

Preventing bacterial development on surfaces is essential to avoid problems caused by biofouling. Surfaces decorated with gold nanoparticles have been shown to thermally kill bacteria under high-intensity NIR illumination. In this study, we evaluated the colonization by E. coli of nanostructured surfaces composed of mesoporous zirconia thin films, both with and without gold nanoparticles embedded into the pores. We studied the effect of the nanostructure and of low intensity visible light excitation of the gold nanoparticles on the colonization process. We found that neither the zirconia, nor the presence of pores, or even gold nanoparticles affect bacterial adhesion compared to the bare glass substrate. Therefore, mesoporous zirconia thin films are biologically inert scaffolds that enable the construction of robust surfaces containing functional nanoparticles that can affect bacterial growth. When the gold containing surfaces are irradiated with light, bacterial adhesion shows a remarkable 96 ± 4% reduction. Our studies revealed that these surfaces affect early colonization steps, prior to biofilm formation, preventing bacterial adhesion without affecting its viability. In contrast to related systems where plasmonic excitation induces membrane damage due to strong local heating, the membrane integrity is preserved, showing that these surfaces have a different working principle.

Mesoporous PdO–loaded WO3 nanocrystals: A promising photocatalyst for highly efficient photoreduction of nitrobenzene to aniline under visible light

BackgroundNitrobenzene (NTB) conversion to aniline (AN) is a key technology for large-scale industrial chemical production and wastewater treatment. Accordingly, photocatalytic reduction of nitrobenzene has emerged as a green technology to produce aniline. MethodsThis study offers a simple nontoxic surfactant-assisted fabrication of mesoporous tungsten oxide (WO3) nanostructures accompanied by the incorporation of tiny contents (0.5‒2.0 wt%) of palladium oxide (PdO) nanoparticles through impregnation and calcination. Significant findingsPhysicochemical investigations of fabricated heterostructures revealed the formation of mesoporous surfaces and showed the implication of PdO loading on textural and optoelectronic characteristics of WO3. Only 2.0 wt% PdO on the WO3 surface caused a notable decline in the energy bandgap from 2.77 to 1.07 eV, confirming visible light-harvesting improvement. The prepared PdO–loaded WO3 was examined for NTB photoreduction to AN. The optimum content of 1.5 wt% PdO/WO3 (2.0 g L–1) exhibited a complete phototransformation of NTB to AN after only 40 min with excellent reusability and recyclability. The PdO loading significantly facilitated photoinduced charge carriers’ separation and mobility through the construction of Step (S)-scheme heterojunction. This work opens the door for developing semiconductor-based photocatalysis as a green process for effectively converting contaminated water into useful value-added chemicals.

Insights into effects of grain boundary engineering in composite metal oxide catalysts for improving catalytic performance

Volatile Organic Compounds (VOCs) have long been a threat to human health. However, designing economical and efficient transition metal composite oxide catalysts for VOCs purification remains a challenge. Herein, this study demonstrates the enormous potential of grain boundary engineering in facilitating VOCs decomposition over ordered mesoporous composite oxide denoted as 3D-MnxCoy (x, y = 1, 3, 5, 7, 9). Specifically, the three-dimensional (3D) Mn7Co1 catalyst shows 100% ethyl acetate removal efficiency for a continuous airflow containing 1000 ppm ethyl acetate over 60000 h−1 space velocity at 160 °C. Mechanism study suggests that the high catalytic performance originates from the lattice distortion caused by the introduction of heteroatoms, along with the size effect of nanopore walls, which leads to the formation of various grain boundaries on the catalyst surface. The presence of grain boundaries facilitates the generation of oxygen vacancies, thus promoting the migration and activation of oxygen species. Furthermore, the near-atmospheric pressure X-ray photoelectron spectroscopy (NAP- XPS) monitoring results reveal that the bimetallic synergy enhanced by grain boundary accelerates the catalytic reaction rate of VOCs through Mn3++Co3+↔Mn4++Co2+ redox cycle. This study may shed light on the great potential of ordered mesoporous bimetallic oxide catalysts in VOCs pollution control.

Packed in-tube solid-phase microextraction with mesoporous zirconium titanium oxides for highly efficient phosphopeptide enrichment and analysis

Phosphorylated peptides are crucial for understanding biological regulation processes. However, the detection of phosphorylated peptides remains challenging in mass spectrometry (MS) due to their high hydration, low abundance, and the significant signal suppression caused by non-phosphorylated peptides. It is essential to enhance the efficiency of phosphopeptide enrichment from complex biological samples to achieve comprehensive analysis and identification of phosphopeptides. Herein, a packed in-tube solid-phase microextraction (IT-SPME) method was developed based on mesoporous zirconium titanium oxides for the selective enrichment and analysis of phosphopeptides. The IT-SPME system achieved the efficient capture of phosphopeptides from complex biological samples followed by high-sensitivity detection (5 fmol). This exceptional performance can be attributed to the high surface area (289.77 m2/g) of mesoporous zirconium titanium oxides, which provided abundant active sites for a high loading capacity. The zirconium titanium oxides with a mesoporous structure (∼4.5 nm) was prepared through a sol–gel and solvothermal process. Importantly, this method proved effective in enriching phosphopeptides from practical samples such as non-fat milk and egg white. It is the first attempt to employ a mesoporous packed IT-SPME approach for phosphopeptide enrichment. These results demonstrate the significant application potential of mesoporous zirconium titanium oxides in phosphoproteomics.

Mesoporous Cu-Doped Manganese Oxide Nano Straws for Photocatalytic Degradation of Hazardous Alizarin Red Dye.

The present work reports the photocatalytic degradation of alizarin red (AR) using Cu-doped manganese oxide (MH16-MH20) nanomaterials as catalysts under UV light irradiation. Cu-doped manganese oxides were synthesized by a very facile hydrothermal approach and characterized by energy dispersive X-ray spectroscopy, powder X-ray diffraction, scanning electron microscopy, Brunauer-Emmett-Teller analysis, UV-vis spectroscopy, and photoluminescence techniques. The structural, morphological, and optical characterization revealed that the synthesized compounds are nanoparticles (38.20-54.10 nm), grown in high mesoporous density (constant C > 100), possessing a tetragonal phase, and exhibiting 2.98-3.02 eV band gap energies. Synthesized materials were utilized for photocatalytic AR dye degradation under UV light which was monitored by UV-visible spectroscopy and % AR degradation was calculated at various time intervals from absorption spectra. More than 60% AR degradation at various time intervals was obtained for MH16-MH20 indicating their good catalytic efficiencies for AR removal. However, MH20 was found to be the most efficient catalyst showing more than 84% degradation, hence MH20 was used to investigate the effect of various catalytic doses, AR concentrations, and pH of the medium on degradation. More than 50% AR degradation was obtained for all studied parameters with MH20 whereas the pseudo-first-order kinetic model was found to be the best-fitted kinetic model for AR degradation with k = 0.0015 and R2 = 0.99 indicating a significant correlation between experimental data.

Application of ultrasound-assisted technique for production of mesoporous magnesium oxide from solid waste of ductile iron: An alternative method for elimination of surfactants from precipitation process

In the present work, the mesoporous magnesium oxide nanoparticles were produced from the solid waste of ductile iron casting industry. Mg2+ ions were extracted from the waste through the acid leaching, and MgO nanoparticles were obtained by the conventional, and ultrasound-assisted methods. Mg(OH)2 nanoparticles was precipitated in the presence of sodium dodecyl sulfate/Triton, 1:1, and under ultrasound irradiation in the absence of mentioned surfactant. The precipitates were then converted to mesoporous MgO via the calcination at 500 °C. The structure of products was evaluated by X-ray diffractometry (XRD), field emission electron microscopy (FESEM), and N2 adsorption-desorption isotherms. Although MgO nanoparticles with the specific surface area of 118 m2 g−1 could be fabricated by the conventional precipitation, the surfactant concentration should be fixed at the level of 1.5 g L−1. The precipitation under ultrasound irradiation is suggested for the clean fabrication of highly porous powder, 0.7586 cm3 g−1, in which the pore diameter is distributed in the range of 2–12 nm. In consequence, the solid waste of ductile iron industry is a potential material for the fabrication of mesoporous MgO by ultrasound- assisted technique in the absence of surfactant.

Mesoporous Ti-substituted NiO nanosheets as an efficient electrocatalyst for triiodide reduction in dye-sensitized solar cells

In this work, a novel two-dimensional hexagonal mesoporous nickel oxide (2D-HM NiO) and titanium substituted NiO (Ti (1, 3, 5, 7 and 9 mol%)-NiO) nanosheets (NSs) are synthesized via a one-step hydrothermal method. The as-prepared 2D-HM NiO and Ti (1–9%)-NiO NSs are used to fabricate cost-effective counter electrodes (CEs) for DSSCs. The DSSCs device made with NiO and 1% of Ti-substituted NiO (1-TNO) CEs show excellent electrochemical properties and photovoltaic performance. The 100 consecutive cycles of cyclic voltammetry (CV) shows that NiO and 1-TNO CEs have high chemical stability towards I−/I3− redox mediator as compared with Pt CE. For the first time, the power conversion efficiency (PCE) of DSSCs with NiO-based CE reached up to 4.08% whereas 1-TNO CE a PCE slightly increased up to 4.12% which is relatively closer to Pt-based CE (5.34%) under identical working conditions. The high performance of NiO and 1-TNO CEs can be attributed to the large number of electrocatalytic active sites and fast ion diffusion, which is due to the high specific surface area of the 2D nanosheet structure with mesoporous nature.

Eco-friendly synthesis of mesoporous praseodymium oxide nanoparticles for highly efficient electrochemical sensing of carmoisine in food samples

Herein, a mesoporous Pr6O11 nanoparticle (NPs) has been prepared via a simple sonochemical process employing an eco-friendly capping agent, grape juice, and utilized for the development of a novel electrochemical sensor to measure carmoisine. Chronoamperometry, cyclic voltammetry (CV), and differential pulse voltammetry (DPV) have been used for the investigation of the electrochemical behavior of mesoporous Pr6O11/Ionic liquid/Carbon paste electrode (MP-Pr6O11/IL/CPE) in the presence of carmoisine. The oxidation behavior of carmoisine has been examined, and it has been discovered that there was a greater enhancing signal with the MP-Pr6O11/IL/CPE. A lowdetection limit of 12 nM in a linear range of 0.09–135 µM was achieved by the novel carmoisine sensor. Good selectivity, repeatability, stability, and reproducibility were all features of the newly constructed sensor. As a result, the suggested procedurewas appropriate for routine analysis and ought to serve as a viable option for analyzing food colorant.

(Invited) Minimizing Thermal Losses at Quantum Dot-Metal Oxide Interfaces for Solar Energy Conversion

The sensitization of mesoporous oxides by semiconductor quantum dots (QDs) represents an appealing route for the development of low-cost solutions for solar energy production and storage (e.g. solar cells and fuel architectures). In order to boost photoconversion efficiency at these technologically relevant interfaces is important to minimize energy losses upon photon absorption; Energy losses that are intimately linked to kinetic completion at the relevant donor-acceptor interface [1]. Two main thermal energy losses can be identified following the absorption of a photon at the QD-oxide interface: firstly, any excess energy of the impinging photon vs the QD absorption onset is generally wasted as heat within the QD donor; secondly, the excess energy between QD electron donating state and the oxide accepting state (bottom of the conduction band) constitutes as well a thermal loss (now within the oxide) which reduces the available energy in the system to produce work. Reducing thermal losses associated with the latter mechanism is mandatory for allowing these architectures to reach efficiencies up to ~33% (the so called Shockley-Queisser limit). Preventing charge carrier cooling within the QD absorber after photon absorption, e.g. by enabling hot electron transfer toward the oxide, could – in principle - pave the way for developing QD dot based hot carrier solar cells with efficiencies beyond the Shockley-Queisser limit.Here I will present, from a charge carrier dynamics perspective, our studies aiming bypassing thermal losses at QD-oxide interfaces. First I will show how attempts to reduced QD-oxide donor-acceptor interfacial energetics by exploiting QD dipolar molecular capping can be in vain in strongly coupled QD-oxide sensitized systems [2]. This is linked to Fermi level pinning at the QD-oxide interface. I will show how this effect can be bypassed by inserting an insulating layer between QD donor and oxide acceptor. In the second part of my talk, I will discuss results demonstrating room-temperature hot electron transfer (HET) in strongly coupled QD-sensitized mesoporous oxides [3]. We quantify HET rates and show that the HET efficiency is determined by interfacial kinetic competition that can be optimized by both, maximizing QD-oxide coupling and/or suppressing electron cooling within the QD. Implications of these results for the challenging development of ultra-high efficiency solar converters will be discussed.

(Invited) Ir-Based Catalysts for the Electrochemical Oxygen Evolution Reaction in Acidic Environments

In order to overcome the inherent intermittent availability of renewable energies and moving forward to a clean and sustainable energy infrastructure, large-scale energy storage and on-demand energy conversion technologies are required to bridge the time gap between energy supply and demand. In this context, hydrogen has great potential as an energy carrier.1,2 The so-called green hydrogen can be produced using excess renewable electricity, stored, transported if necessary, and finally converted into electrical energy. Promising devices to produce green hydrogen are proton exchange membrane water electrolyzers (PEMWEs).3,4 PEMWEs combine high energy efficiency and high gas purity with flexible partial load capabilities and fast dynamic behavior, which are prerequisite for grid balancing.3,4 However, one of the major drawbacks of PEMWEs is the requirement of large amounts of noble metals in the electrocatalysts due to the inherent highly corrosive acidic working environment.3 In PEMWEs, the anodic oxygen evolution reaction (OER) is undoubtedly demanding from a catalyst standpoint and is mostly responsible for the efficiency loss.5 To date, iridium, one of the least abundant elements in Earth’s crust, is required as the electrocatalyst for the OER in PEMWEs.4,6-8 As a result, in order to facilitate the large-scale application of PEMWEs, developing low-noble metal content, stable electrocatalysts for the OER is requisite.In this talk I present collective results of our research on Ir-based electrocatalysts for the electrochemical OER in acidic environments. To lower the Ir loading in OER catalysts while maintaining or improving the activity, we applied different strategies. One strategy was to synthesize binary alloy nanoparticles (NPs) of Ir and an abundant non-noble metal, transforming them into core-shell NPs consisting of Ir-rich shells and low-Ir content cores.9 Another strategy was to use doped mesoporous oxides as support materials to disperse the catalyst NPs. The doped oxides offered improved corrosion resistance combined with large surface area and adequate electronic conductivity. Moreover, they showed synergistic interactions with the catalysts, improving activity and stability.10,11 Considering the synthesis of catalyst-oxide support couples, it is generally challenging to anchor catalyst NPs on oxide supports due to their incompatible surface properties. Hence we developed a new concept to synthesize oxide supported IrOx catalysts by modifying the surface charge of the catalyst or oxide prior to dispersing the catalyst on the oxide.12 These synthesis routes and strategies can be applied to other noble catalyst systems, pointing out a path forward to nanostructured electrodes with substantially reduced noble metal content and improved efficiency.Importantly, deeper insights into the origin of the OER activity and the OER mechanism on Ir-based electrocatalysts are needed in order to aid in rational design of OER electrocatalysts. Combining electrocatalytic investigations with operando materials characterization techniques and DFT calculations, we identified that the p-band holes in the oxygen ligands play a key role in the OER activity of Ir-based catalysts, in addition, we showed that the rate-determining step for the OER on IrOx is driven by the strong oxidizing power of the deprotonated Ir–O sites and not by an electrostatic-potential gradient across the electrodes double layer.13,14 These findings bridge the gap between thermal catalysis and electrocatalysis and emphasize the ultimate importance to investigate and understand heterogeneous electrocatalytic reactions from different perspectives. References Liu, W.et al., Environmental Science and Pollution Research 2020, 27 (25), 31092-31104.Møller, K. T.et al., Progress in Natural Science: Materials International 2017, 27 (1), 34-40.Carmo, M.et al., J. Hydrog. Energy 2013, 38 (12), 4901-4934.Shirvanian, P.; van Berkel, F., Commun. 2020, 114, 106704.Dau, H.et al., ChemCatChem 2010, 2 (7), 724-761.Greenwood, N. N.; Earnshaw, A.,Chemistry of the Elements. Butterworth–Heinemann: Oxford, 1997; p 1600.Lei, Z.et al., Advanced Energy Materials 2020, 10 (23), 2000478.Alaswad, A.et al., Energies 2021, 14 (1), 144.Nong, H.N. et al., Chem.Sci.2014, 5, 8, 2955-2963.Nong, H.N. et al., Chem. Int. Ed.2015, 54, 2975-2979.Oh, H.S. et al., J.Am. Chem. Soc., 2016, 138, 38, 12552–12563.Tran, H.P. et al., Chem. Mater. 2022, 34, 21, 9350–9363.Nong, H.N. et al., Nature Catalysis 2018, 1, 841-851Nong, H. N.et al., Nature 2020, 587 (7834), 408-413.

Novel template free synthesis of high surface area mesoporous ceria and adaptive neuro fuzzy interference system (ANFIS) modelling for Cr(VI) adsorption

The search for sustainable and ecofriendly mesoporous materials with high surface area is intensively desired for catalytic applications. Herein, we explore a template-free hydrothermal method for synthesizing mesoporous Cerium Oxide (meso-CeO2) nanoparticles as an adsorbent, for the removal of toxic hexavalent chromium Cr(VI) from water. The morphology and structure of synthesized nanomaterials were characterized using various techniques such as X-ray diffraction (XRD), scanning electron microscope (SEM), UV–visible spectrophotometer (UV–Vis), Fourier transform infrared spectroscopy (FTIR), and Brunauer, Emmett, and Teller(BET) analysis. The BET analysis confirmed CeO2 possess a high surface area of 270 m2/g, a 4.5 nm pore diameter, 0.22 cm3/g pore volume, and a stable mesoporous structure. The synthesized meso-CeO2, exhibited efficient removal (99.8% at pH 5) of Cr (VI) from water within 60 min at room temperature. The meso-CeO2 material demonstrated reusability for up to 5 cycles. The removal of Cr (VI) using meso-CeO2 followed Pseudo-second order kinetics (R2 > 0.99) and showed a good fit with the Freundlich isotherm model. Moreover, adaptive neuro fuzzy inference system (ANFIS) models were employed on 320 experimental data sets to predict the adsorption process accurately. Overall, this study highlights the potential of meso-CeO2 nanoparticles as a promising adsorbent for effective water remediation of heavy metal contaminants like Cr (VI).

Ultrathin mesoporous BiOCl nanosheets-mediated liposomes for photoelectrochemical immunoassay with in-situ signal amplification

Designing new biochemical sensors and achieving selectivity and high-sensitivity analysis is one of main research directions for immunoassays. Herein, a liposome-amplification photoelectrochemical (PEC) immunoassay was developed using ultrathin mesoporous bismuth chloride oxide nanosheets (BiOCl MSCN) for the highly selective and sensitive detection of carcinoembryonic antigen (CEA). Based on good photocurrent response of BiOCl MSCN toward dopamine, a liposome-conjugated secondary antibody loaded with dopamine was added for specific recognition in the presence of CEA. After the lysis treatment, the liberated dopamine was injected into the three-electrode electrolytic cell to enhance the photocurrent of BiOCl MSCN. Under the optimized conditions, the constructed liposome-mediated PEC immunoassay showed high sensitivity against CEA, with a dynamic response in the linear range of 0.05 ng mL−1 to 100 ng mL−1 and a detection limit of 35 pg mL−1. The present study proposes a new approach to the liposome-mediated PEC immunoassay constructed on ultrathin mesoporous BiOCl nanosheets, which can be used to target further the study of the sensing mechanism.

Integration of MyD88 inhibitor into mesoporous cerium oxide nanozymes-based targeted delivery platform for enhancing treatment of ulcerative colitis

Excessive reactive oxygen species (ROS) and stressed inflammatory response are major characteristics of ulcerative colitis, which cause disease progression and aggravation. Herein, a novel mesoporous cerium oxide nanozymes (MCN) was designed and then loaded with Myeloid differentiation factor-88 (MyD88) inhibitor for synergistic treatment of colitis by scavenging ROS and regulating inflammation. This innovative MCN with average particle size of 200.7 nm, specific surface area of 119.78 m2/g and mesopores of 4.47 nm not only exhibited excellent SOD-like and CAT-like activities to scavenge ROS but also could act as a carrier to load MyD88 inhibitor, TJ-M2010–5, (abbreviated as TJ-5) into their mesopores, achieving the effect of ‘two birds with one stone’. Besides, the modification of dextran sulfate sodium (TJ-5/MCN/DSS) increased the internalization of nanozymes into activated macrophages and enhanced in vitro anti-inflammatory ability. To enhance colon targeting, we coated TJ-5/MCN/DSS with the enteric material Eudragit S100, preventing premature release or absorption of the drug in the gastrointestinal tract after oral administration. The results demonstrated that TJ-5/MCN/DSS/Eudragit not only achieved delayed drug release and improved colon targeting but also exhibited optimal therapeutic efficacy in colitis mice. Mechanistically, the MCN-mediated ROS scavenging and TJ-5-mediated MyD88 blockade synergistically inhibited the NF-κB signaling pathway, thereby reducing the inflammatory response. Importantly, TJ-5/MCN/DSS/Eudragit did not induce systemic toxicity. In conclusion, our work not only presents a novel carrier capable of scavenging ROS but also provides proof of concept for the synergistic treatment of colitis using this carrier in combination with MyD88 inhibitors. This study proposes a safe and efficient strategy for targeting ROS-associated inflammation.

Alkaloid Precipitant Reaction Inspired Controllable Synthesis of Mesoporous Tungsten Oxide Spheres for Biomarker Sensing.

Highly porous sensitive materials with well-defined structures and morphologies are extremely desirable for developing high-performance chemiresistive gas sensors. Herein, inspired by the classical alkaloid precipitant reaction, a robust and reliable active mesoporous nitrogen polymer sphere-directed synthesis method was demonstrated for the controllable construction of heteroatom-doped mesoporous tungsten oxide spheres. In the typical synthesis, P-doped mesoporous WO3 monodisperse spheres with radially oriented channels (P-mWO3-R) were obtained with a diameter of ∼180 nm, high specific surface area, and crystalline skeleton. The in situ-introduced P atoms could effectively adjust the coordination environment of W atoms (Wδ+-Ov), giving rise to dramatically enhanced active surface-adsorbed oxygen species and unusual metastable ε-WO3 crystallites. The P-mWO3-R spheres were applied for the sensing of 3-hydroxy-2-butanone (3H2B), a biomarker of foodborne pathogenic bacteria Listeria monocytogenes (LM). The sensor exhibited high sensitivity (Ra/Rg = 29 to 3 ppm), fast response dynamics (26/7 s), outstanding selectivity, and good long-term stability. Furthermore, the device was integrated into a wireless sensing module to realize remote real-time and precise detection of LM in practical applications, making it possible to evaluate food quality using gas sensors conveniently.

Bifunctional vanadium doped mesoporous Co3O4 on nickel foam towards highly efficient overall urea and water splitting in the alkaline electrolyte

Developing more active and stable electrode materials for oxygen evolution reaction (OER) and urea oxidation reaction (UOR) is necessary for electrocatalytic water and urea oxidation which can be used to generate hydrogen. Here, a low-cost vanadium-doped mesoporous cobalt oxide on Ni foam (V/meso-Co/NF) electrodes are obtained via the grouping of an in-situ citric acid (CA)-assisted evaporation-induced self-assembly (EISA) method and electrophoretic deposition process, and work as highly efficient and long-lasting electrocatalytic materials for OER/UOR. In particular, V/meso-Co/NF electrodes require 329 mV overpotential to maintain a 50 mA/cm2, with exceptional long-term durability of 30 h. Interestingly, V/meso-Co/NF also exhibits excellent electrocatalytic UOR performance, reaching 50 and 100 mA/cm2 versus RHE at low potentials of 1.34 and 1.35 V, respectively. By employing the V/meso-Co/NF materials as both the anode and cathode, this urea electrolysis assembly V/meso-Co/NF-5 (+,−) reaches current densities of 100 mA cm−2 at 1.62 V in KOH/urea, which is nearly 340 mV lesser than classical water electrolysis. The V/meso-Co/NF-5 electrocatalysts also exhibit remarkable durability for electrocatalytic OERs and UORs. The obtained findings revealed that the synthesized V/meso-Co/NF might be a promising electrode materials for overall urea-rich wastewater management and H2 generation from wastewater.

Removal of chromium (VI) using spirulina assisted synthesized mesoporous iron oxide nanoparticles

Worldwide demand for clean and safe drinking water is a serious concern due to sharply rising industrialization and the growing population. In this work, Spirulina (microalgae) based green synthesis of mesoporous iron oxide nanoparticles (MIONPs) was performed for the adsorption of chromium (VI) in an aqueous solution. Synthesized MIONPs were characterized by XRD, FT-IR, Raman Spectroscopy, Zeta Potential, Particle Size Analyzer, and FESEM with EDX. The mesoporous nature of synthesized material was confirmed using Brunauer–Emmett–Teller (BET) with a pore diameter of 3.837 nm. The adsorption mechanism of Chromium (VI) by synthesized MIONPs was explained using XPS analysis. The various other parameters including pH, Temperature, ion concentration, adsorbent dose, and contact time were also studied in batch experiments for chromium removal. The synthesized material shows the best adsorption efficiency on pH 2, 100 min of contact time, and a temperature of 70 ℃. The Langmuir isotherm model with an adsorption efficiency of 92.8505 mg/g shows better adsorption than the Freundlich isotherm model for synthesized material. The pseudo-second-order model with chemisorption kinetics explains better chromium adsorption with an R2 value of 0.99863 than the pseudo-first-order model. Regeneration studies analyse the recyclable use of green synthesized MIONPs during the adsorption of chromium. This study could be useful for the removal of multiple heavy metals at a time from drinking water safely without harming the ecosystem and hence it is employable to meet the sustainability goals.

Honeycomb-like SBA-15 parceled in 2D GO for ultrafiltration membranes fabrication with ultrahigh permeability and enhanced anti-fouling performance

Novel 3D mesoporous silica SBA-15 and 2D graphene oxide (GO) composite nano-fillers incorporated polysulfone (PSf) ultrafiltration (UF) membranes (GO-SBA-15/PSf) were first prepared via blending modifications by non-solvent induced phase separation (NIPs). 3D honeycomb-like SBA-15 not only improved the surface hydrophilicity but also provided extra nano-channels parceled in 2D GO networks for convenient hydrone transport via confinement-effect. The lamellar GO networks relieved the agglomeration of inorganic materials inside the polymer, anticipating in the interfacial polymerization reaction. GO-SBA-15/PSf UF membranes were systematically investigated using contact angle, scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscope (AFM) and Brunauer-Emmett-Teller (BET) methods. The pure water flux reached 641.7 L m-2h−1 which was 3 times than that of pristine PSf membranes (229.2 L m-2h−1) under the pressure of 0.1 MPa. Negative charge of GO generated electrostatic repulsion with protein, which facilitated a high rejection of 98.22% and excellent FRR value of 85% that was 1.5 times than that of pristine PSf membranes (58%). The UF membranes fabricated by new multidimensional nano-fillers overcame the trade-off effect between permeability and protein rejection.