CeO2·ZnO@biomass-derived carbon nanocomposite-based electrochemical sensor for efficient detection of ascorbic acid.

Ascorbic acid (AA), a prominent antioxidant commonly found in human blood serum, serves as a biomarker for assessing oxidative stress levels. Therefore, precise detection of AA is crucial for swiftly diagnosing conditions arising from abnormal AA levels. Consequently, the primary aim of this research is to develop a sensitive and selective electrochemical sensor for accurate AA determination. To accomplish this aim, we used a novel nanocomposite comprised of CeO2-doped ZnO adorned on biomass-derived carbon (CeO2·ZnO@BC) as the active nanomaterial, effectively fabricating a glassy carbon electrode (GCE). Various analytical techniques were employed to scrutinize the structure and morphology features of the CeO2·ZnO@BC nanocomposite, ensuring its suitability as the sensing nanomaterial. This innovative sensor is capable of quantifying a wide range of AA concentrations, spanning from 0.5 to 1925 µM in a neutral phosphate buffer solution. It exhibits a remarkable sensitivity of 0.2267 µA µM-1cm-2 and a practical detection limit of 0.022 µM. Thanks to its exceptional sensitivity and selectivity, this sensor enables highly accurate determination of AA concentrations in real samples. Moreover, its superior reproducibility, repeatability, and stability underscore its reliability and robustness for AA quantification.

Gold nanoparticles plated porous silicon nanopowder for nonenzymatic voltammetric detection of hydrogen peroxide.

A voltammetric approach was developed for the selective and sensitive determination of hydrogen peroxide using Au plated porous silicon (PSi) nanopowder modified glassy carbon electrode (GCE). The AuNPs-PSi hybrid structure was synthesized via stain etching procedure followed by an immersion plating method to deposit AuNPs onto PSi via a simple galvanic displacement reaction with no external reducing agent to convert Au3+ to Au0. The as-fabricated AuNPs-PSi catalyst was successfully characterized by XRD, Raman, FTIR, XPS, SEM, TEM and EDS techniques. Well crystalline nature of the as-fabricated hybrid structure with AuNPs size ranging from 5 to 40 nm was observed. The specific surface area and total pore volume for both PSi and AuNPs plated PSi were evaluated using N2 adsorption isotherm technique. Cyclic voltammetry and electrochemical impedance spectroscopy techniques were applied to investigate the catalytic efficiency of AuNPs-PSi modified electrode compared to pure PSi/GCE and unmodified GCE. The sensing performance of the active material modified GCE was thoroughly examined with linear sweep voltammetry (LSV) and square wave voltammetry (SWV) techniques. The AuNPs-PSi/GCE exhibited a remarkable linear dynamic range between 2.0 and 13.81 mM (for LSV) and 0.5-6.91 mM for (SWV) with high sensitivity and low detection limit of 10.65 µAmM-1cm-2 and 14.84 µM for LSV, whereas 10.41 µAmM-1cm-2 and 15.16 µM using SWV techniques, respectively. The fabricated sensor electrode showed excellent anti-interfering ability in the presence of several common biomolecules as well as demonstrated good operational stability and reproducibility with low relative standard deviation. Moreover, the modified electrode showed acceptable recovery of H2O2 in a real sample analysis. Thus, the developed AuNPs-PSi hybrid nanomaterial represents an excellent electrocatalyst for the efficient detection and quantification of H2O2 by the electrochemical approach.

Tetracyanonickelate (II)/KOH/reduced graphene oxide fabricated carbon felt for mediated electron transfer type electrochemical sensor for efficient detection of N2O gas at room temperature.

N2O is the most significant anthropogenic greenhouse gas, which cause the ozone depletion. Hence, the room temperature detection of N2O is highly desirable. In this work, The TCN(II)-KOH-rGO/CF modified electrode was successfully fabricated by drop coating method. The synthesized electrode was successfully characterized by SEM, TEM, FT-IR and XRD. The sensor electrode was used to detect different N2O concentration in flow conditions at room temperature. TCN(II)-KOH-rGO/CF modified electrode showed high sensitivity towards N2O, a wide range from 1ppm to 16 ppm and low detection of 1 ppm N2O were achieved for the TCN(II)-KOH-rGO/CF modified electrode. The limit of detection and the response towards this nitrogen oxide is competitive to other sensing methods. In addition, the sensitivity of the electrochemical sensor electrode was compared with the online Gas Chromatography. Additionally, the selectivity of the working electrode was analyzed and specified. The working electrode stability was analyzed for more than 30 days shows good stability. The fabricated TCN(II)-KOH-rGO/CF electrode is easier to prepare to get excellent analytical performance towards N2O. Hence, the proposed TCN(II)-KOH-rGO/CF electrode could be the suitable material for detection of N2O in the real site process.

Carboxymethyl-imidazolium O-vanillin Schiff base grafted into NH2-tagged MIL-101 (Cr) for effective removal of cupric ions from aqueous effluents.

A novel adsorbent (MIL-CMIVSB) was fabricated by modification of H2N-MIL-101(Cr) with carboxymethyl-imidazolium O-vanillin Schiff base. The MIL-CMIVSB's physicochemical characteristics were examined using the pertinent characterization methods. NH2-MIL-101(Cr) has a BET surface area of 1492.4 m2g-1, while MIL-CMIVSB adsorbent had 1278.7 m2g-1. Batch adsorption experiments examined the MIL-CMIVSB's cupric ion adsorption capacity from aqueous solutions at different adsorbent doses (0.1-3 mg), pH (2.0-10.0), contact times (0-240 min), metal ion initial concentrations (10-300 mg/L), and temperatures (298-308 K). The optimum conditions were 1 mg/mL of MIL-CMIVSB adsorbent, 46 min adsorption time, pH 7, 100 ppm initial cupric ion concentration, and 303 K temperature. MIL-CMIVSB effectively and selectively removes cupric ions with an adsorption capability of 359.05 ± 12.06 mg/g. The nonlinear Liu isotherm governed Cu(II) sorption performance on MIL-CMIVSB (KL = 0.257 ± 0.01 mg/g, R2 = 0.99892) and pseudo-2nd-order kinetically (k2 = 0.00116 × 10-4 g/mg min, R2 = 0.99721).

Dielectric Barrier Discharge Plasma Processing and Sr-Doped ZnO/CNT Photocatalyst Decoration of Cotton Fabrics for Self-Cleaning Application.

Nonthermal plasma processing is a chemical-free and environmentally friendly technique to enhance the self-cleaning activity of nanoparticle-coated cotton fabrics. In this research, Sr-doped ZnO/carbon nanotube (CNT) photocatalysts, namely, S10ZC2, S15ZC2, and S20ZC2 with different Sr doping concentrations, were synthesized using the sol-gel method and coated on plasma-functionalized fabric to perform the self-cleaning tests. The fabrics were treated with dielectric barrier discharge plasma in an open environment for 3 min to achieve a stable coating of nanoparticles. The energy band gap of the photocatalyst decreased with an increase in the level of Sr doping. The band gap of S10ZC2, S15ZC2, and S20ZC2 photocatalysts was estimated to be 2.85, 2.78, and 2.5 eV, respectively. The hexagonal wurtzite structure of ZnO was observed on the fabric surface composited with CNTs and Sr. The S20ZC2 photocatalyst showed better homogeneity and photocatalytic response on the fabric when compared with S10ZC2- and S15ZC2-coated fabrics. The S20ZC2 photocatalyst showed 89% dye degradation efficiency after 4 h of light exposure in methylene blue solution, followed by S15ZC2 (84%) and S10ZC2 (80%) photocatalysts.

Smart waste management perspective of COVID-19 healthy personal protective materials in concrete for decorative landscape pavements and artificial rocks.

This paper presents a new method for determining the effect of healthy personal protective material (HPPM) stripes, such as surgical masks, protective suits, and overhead and foot covers, on the durability and physicomechanical characteristics of concrete for use in architectural forms. Because of the current global epidemic caused by coronavirus (COVID-19), the use of HPPM, such as surgical masks, protective suits, and overhead and foot covers, has increased considerably. COVID-19's second and third waves are currently affecting various countries, necessitating the use of facemasks (FM). Consequently, millions of single FM have been discharged into the wild, washing up on beaches, floating beneath the seas, and ending up in hazardous locations. The effect of stripe fibers on the physicomechanical characteristics of concrete, such as the workability, Uniaxial Compressive Strength UCS, flexural strength, impact strength, spalling resistance, abrasion resistance, sorptivity, Water absorption Sw, porosity (ηe), water penetration, permeability, and economic and eco-friendly aspects, need to be determined. With a focus on HPPM, especially single-use facemasks, this study investigated an innovative way to incorporate pandemic waste into concrete structures. Scanning electron microscope and X-ray diffraction patterns were employed to analyze the microstructures and interfacial transition zones and to identify the elemental composition. The HPPM had a pore-blocking effect, which reduced the permeability and capillary porosity. Additionally, the best concentrations of HPPM, particularly of masks, were applied by volume at 0, 1, 1.5, 2.0, and 2.5%. The use of mixed fibers from different HPPMs increased the strength and overall performance of concrete samples. The tendency of growing strength began to disappear at approximately 2%. The results of this investigation showed that the stripe content had no effect on the compressive strength. However, the stripe is critical for determining the flexural strength of concrete. The UCS increased steadily between 1 and 1.5% before falling marginally at 2.5%, which indicates that incorporating HPPM into concrete had a significant impact on the UCS of the mixture. The addition of HPPM to the mixtures considerably modified the failure mode of concrete from brittle to ductile. Water absorption in hardened concrete is reduced when HPPM stripes and fibers were added separately in low-volume fractions to the concrete mixture. The concrete containing 2% HPPM fibers had the lowest water absorption and porosity percentage. The HPPM fibers were found to act as bridges across cracks, enhancing the transfer capability of the matrices. From a technological and environmental standpoint, this study found that using HPPM fibers in the production of concrete is viable.

Methyl esters synthesis from Luffa cylindrica seeds oil using green copper oxide nanoparticle catalyst in membrane reactor.

This study investigates the potential role of Juglans sp. root extract-mediated copper oxide nanoparticles of Luffa cylindrica seed oil (LCSO) into methyl esters. The synthesized green nanoparticle was characterized by Energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), and Scanning electron microscopy (SEM) spectroscopies to find out the crystalline size (40 nm), surface morphology (rod shape), particle size (80-85 nm), and chemical composition (Cu = 80.25% & O = 19.75%), accordingly. The optimized protocol for the transesterification reaction was adjusted as oil to methanol molar ratio (1:7), copper oxide nano-catalyst concentration (0.2 wt %), and temperature (90 °C) corresponding to the maximum methyl esters yield of 95%. The synthesized methyl esters were characterized by GC-MS, 1H NMR, 13C NMR, and FT-IR studies to know and identify the chemical composition of newly synthesized Lufa biodiesel. The fuel properties of Luffa cylindrica seed oil biofuel were checked and compared with the American Biodiesel standards (ASTM) (D6751-10). Finally, it is commendable to use biodiesel made from wild, uncultivated, and non-edible Lufa cylindrica to promote and adopt a cleaner and sustainable energy method. The acceptance and implementation of the green energy method may result in favourable environmental effects, which in turn may lead to better societal and economic development.

Rapid elimination of antibiotic gemifloxacin mesylate and methylene blue over Pt nanoparticles dispersed chitosan/g-C3N4 ternary visible light photocatalyst.

Appropriate material selection and proper understanding of bandgap modification are key factors for the development of efficient photocatalysts. Herein, we developed an efficient, well-organized visible light oriented photocatalyst based on g-C3N4 in association with polymeric network of chitosan (CTSN) and platinum (Pt) nanoparticles utilizing a straightforward chemical approach. Modern techniques like XRD, XPS, TEM, FESEM, UV-Vis, and FTIR spectroscopy were exploited for characterization of synthesized materials. XRD results confirmed the involvement of α-polymorphic form of CTSN in graphitic carbon nitride. XPS investigation confirmed the establishment of trio photocatalytic structure among Pt, CTSN, and g-C3N4. TEM examination showed that the synthesized g-C3N4 possesses fine fluffy sheets like structure (100 to 500 nm in size) intermingled with a dense layered framework of CTSN with good dispersion of Pt nanoparticles on g-C3N4 and CTSN composite structure. The bandgap energies for g-C3N4, CTSN/g-C3N4, and Pt@ CTSN/g-C3N4 photocatalysts were found to be 2.94, 2.73, and 2.72 eV, respectively. The photodegradation skills of each created structure have been examined on antibiotic gemifloxacin mesylate and methylene blue (MB) dye. The newly developed Pt@CTSN/g-C3N4 ternary photocatalyst was found to be efficacious for the elimination of gemifloxacin mesylate (93.3%) in 25 min and MB (95.2%) just in 18 min under visible light. Designed Pt@CTSN/g-C3N4 ternary photocatalytic framework exhibited ⁓ 2.20 times more effective than bare g-C3N4 for the destruction of antibiotic drug. This study provides a simple route towards the designing of rapid, effective visible light oriented photocatalyts for the existing environmental issues.

Low Overpotential Amperometric Sensor Using Yb2O3.CuO@rGO Nanocomposite for Sensitive Detection of Ascorbic Acid in Real Samples.

The ultimate objective of this research work is to design a sensitive and selective electrochemical sensor for the efficient detection of ascorbic acid (AA), a vital antioxidant found in blood serum that may serve as a biomarker for oxidative stress. To achieve this, we utilized a novel Yb2O3.CuO@rGO nanocomposite (NC) as the active material to modify the glassy carbon working electrode (GCE). The structural properties and morphological characteristics of the Yb2O3.CuO@rGO NC were investigated using various techniques to ensure their suitability for the sensor. The resulting sensor electrode was able to detect a broad range of AA concentrations (0.5-1571 µM) in neutral phosphate buffer solution, with a high sensitivity of 0.4341 µAµM-1cm-2 and a reasonable detection limit of 0.062 µM. The sensor's great sensitivity and selectivity allowed it to accurately determine the levels of AA in human blood serum and commercial vitamin C tablets. It demonstrated high levels of reproducibility, repeatability, and stability, making it a reliable and robust sensor for the measurement of AA at low overpotential. Overall, the Yb2O3.CuO@rGO/GCE sensor showed great potential in detecting AA from real samples.

Application of QPPO/PVA based commercial anion exchange membrane as an outstanding adsorbent for the removal of Eosin-B dye from wastewaters.

Commercially available QPPO/PVA based anion exchange membrane (AEM) BIII was to inquire the percentage discharge of anionic dye Eosin-B (EB) at terrain temperature from wastewater. The impact of EB initial concentration, membrane dosage, ionic strength, contact time and temperature on EB percentage removal was contemplated. The EB percentage removal was increased from 22 to 99.56% and 38.15-99.56% with contact time and membrane dosage respectively while decreased from 99.56 to 29%, 99.56 to 54.61% and 99.56 to 92.22% with enhancing initial concentration of EB, ionic strength and temperature respectively. Nonlinear isotherm models were utilized to demonstrate EB adsorption onto AEM BIII. Attained results exhibited that nonliner Freundlich isotherm model best fitted to EB adsorption onto AEM BIII. For EB adsorption onto AEM BIII, adsorption kinetics were inquired in detail by using several kinetic models but EB adsorption nicely fitted to pseudo-second-order kinetics. Similarly thermodynamic analysis was performed and results pointed to an exothermic adsorption of EB onto AEM BIII. The membrane could be reused for four concecutive cycles with loosing its efficiency.

Transformation of waste seed biomass of Cordia myxa into valuable bioenergy through membrane bioreactor using green nanoparticles of indium oxide.

Depletion of non-renewable fuel has obliged researchers to seek out sustainable and environmentally friendly alternatives. Membranes have proven to be an effective technique in biofuel production for reaction, purification, and separation, with the ability to use both porous and non-porous membranes. It is demonstrated that a membrane-based sustainable and green production can result in a high degree of process intensification, whereas the recovery and repurposing of catalysts and alcohol are anticipated to increase the process economics. Therefore, in this study sustainable biodiesel was synthesized from inedible seed oil (37 wt%) of Cordia myxa using a membrane reactor. Transesterification was catalyzed by heterogenous nano-catalyst of indium oxide prepared with leaf extract of Boerhavia diffusa. Highest biodiesel yield of 95 wt% was achieved at methanol to oil molar ratio of 7:1, catalyst load 0.8 wt%, temperature 82.5 °C and time 180 min In2O3 nanoparticles exhibited reusability up to five successive transesterification rounds. The production of methyl esters was confirmed using Fourier-transform infrared spectroscopy and Nuclear Magnetic Resonance. The predominant fatty acid methyl ester detected in the biodiesel was 5, 8-octadecenoic acid. Biodiesel fuel qualities were determined to be comparable to worldwide ASTM D-6571 and EN-14214 standards. Finally, it was concluded that membrane technology can result in a highly intensified reaction process while efficient recovery of both nano catalysts and methanol increases the economics of transesterification and lead to sustainable production.

Effect of Ionic Liquids on Mechanical, Physical, and Antifungal Properties and Biocompatibility of a Soft Denture Lining Material.

This study aims to evaluate the effect of ionic liquids and their structure on the mechanical (tensile bond strength (TBS) and Shore A hardness), mass change, and antifungal properties of soft denture lining material. Butyl pyridinium chloride (BPCL) and octyl pyridinium chloride (OPCL) were synthesized, characterized, and mixed in concentrations ranging from 0.65-10% w/w with a soft denture liner (Molloplast-B) and were divided into seven groups (C, BPCL1-3, and OPCL1-3). The TBS of bar-shaped specimens was calculated on a Universal Testing Machine. For Shore A hardness, disc-shaped specimens were analyzed using a durometer. The mass change (%) of specimens was calculated by the weight loss method. The antifungal potential of ionic liquids and test specimens was measured using agar well and disc diffusion methods (p ≤ 0.05). The alamarBlue assay was performed to assess the biocompatibility of the samples. The mean TBS values of Molloplast-B samples were significantly lower (p ≤ 0.05) for all groups except for OPCL1. Compared with the control, the mean shore A hardness values were significantly higher (p ≤ 0.05) for samples in groups BPCL 2 and 3. After 6 weeks, the OPCL samples showed a significantly lower (p ≤ 0.05) mass change as compared to the control. Agar well diffusion methods demonstrated a maximum zone of inhibition for 2.5% OPCL (20.5 ± 0.05 mm) after 24 h. Disc diffusion methods showed no zones of inhibition. The biocompatibility of the ionic liquid-modified sample was comparable to that of the control. The addition of ionic liquids in Molloplast-B improved the liner's surface texture, increased its hardness, and decreased its % mass change and tensile strength. Ionic liquids exhibited potent antifungal activity.

A Sensitive Hydroquinone Amperometric Sensor Based on a Novel Palladium Nanoparticle/Porous Silicon/Polypyrrole-Carbon Black Nanocomposite.

Exposure to hydroquinone (HQ) can cause various health hazards and negative impacts on the environment. Therefore, we developed an efficient electrochemical sensor to detect and quantify HQ based on palladium nanoparticles deposited in a porous silicon-polypyrrole-carbon black nanocomposite (Pd@PSi-PPy-C)-fabricated glassy carbon electrode. The structural and morphological characteristics of the newly fabricated Pd@PSi-PPy-C nanocomposite were investigated utilizing FESEM, TEM, EDS, XPS, XRD, and FTIR spectroscopy. The exceptionally higher sensitivity of 3.0156 µAµM-1 cm-2 and a low limit of detection (LOD) of 0.074 µM were achieved for this innovative electrochemical HQ sensor. Applying this novel modified electrode, we could detect wide-ranging HQ (1-450 µM) in neutral pH media. This newly fabricated HQ sensor showed satisfactory outcomes during the real sample investigations. During the analytical investigation, the Pd@PSi-PPy-C/GCE sensor demonstrated excellent reproducibility, repeatability, and stability. Hence, this work can be an effective method in developing a sensitive electrochemical sensor to detect harmful phenol derivatives for the green environment.

Efficient application of newly synthesized green Bi2O3 nanoparticles for sustainable biodiesel production via membrane reactor.

Introduction of waste and non-edible oil seeds coupled with green nanotechnology offered a pushover to sustainable and economical biofuels and bio refinery production globally. The current study encompasses the synthesis and application of novel green, highly reactive and recyclable bismuth oxide nanocatalyst derived from Euphorbia royealeana (Falc.) Boiss. leaves extract via biological method for sustainable biofuel synthesis from highly potent Cannabis sativa seed oil (34% w/w) via membrane reactors. Advanced techniques such as X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Diffraction X-Ray (EDX), and FT-IR were employed to illustrate the newly synthesized green bismuth oxide nanoparticles. 92% of FAMEs were produced under optimal reaction conditions such as a 1.5% w/w catalyst weight, 1:12 oil to methanol molar ratio, and a reaction temperature of 92 ⸰C for 3.5 h via membrane reactor. The synthesized Cannabis biodiesel was identified using the FT-IR and GC-MS techniques. The fuel properties of synthesized biofuels (acid number 0.203 mg KOH/g, density 0.8623 kg/L, kinematic viscosity 5.32 cSt, flash point 80 °C, pour point -11 °C, cloud point -11 °C, and Sulfur 0.00047 wt %, and carbon residues 0.2) were studied and established to be comparable with internationally set parameters. The experimental data (R2 = 0.997) shows that this reaction follow pseudo first-order kinetics. These findings affirm the application of green bismuth oxide nanoparticles as economical, highly reactive and eco-friendly candidate for industrial scale biodiesel production from non-edible oil seeds.

Gold Nanoparticle-Loaded Silica Nanospheres for Sensitive and Selective Electrochemical Detection of Bisphenol A.

In this work, silica nanospheres were used as support for gold nanoparticles and applied for bisphenol A electrochemical detection. The development of new silica-supported materials has attracted increasing attention in the scientific world. One approach of interest is using silica nanospheres as support for gold nanoparticles. These materials have a variety of applications in several areas, such as electrochemical sensors. The obtained materials were characterized by solid-state UV-vis spectroscopy, electron microscopy, X-ray diffraction, and electrochemical techniques. The electrode modified with AuSiO2700/CHI/Pt was applied as an electrochemical sensor for BPA, presenting an oxidation potential of 0.842 V and a higher peak current among the tested materials. The AuSiO2700/CHI/Pt electrode showed a logarithmic response for the detection of BPA in the range of 1-1000 nmol L-1, with a calculated detection limit of 7.75 nmol L-1 and a quantification limit of 25.8 nmol L-1. Thus, the electrode AuSiO2700/CHI/Pt was presented as a promising alternative to an electrochemical sensor in the detection of BPA.

Comprehensive Analysis of Spinel-Type Mixed Metal Oxide-Functionalized Polysulfone Membranes toward Fouling Resistance and Dye and Natural Organic Matter Removal.

Nanostructured polymeric membranes are of great importance in enhancing the antifouling properties during water filtration. Nanomaterials with tunable size, morphology and composition, surface modification, and increased functionality provide considerable opportunities for effective wastewater treatment. Thus, in this work, an attempt has been made to use spinel-structured MnCo2O4 as a nanofiller in the fabrication of nanostructured polysulfone (PSF) mixed matrix membranes and is investigated in terms of morphology, hydrophilicity, permeability, protein and natural organic matter separation, dye removal, and, finally, antifouling properties. The MnCo2O4 nanomaterials are synthesized and characterized via X-ray diffraction and field emission scanning electron microscopy and are loaded into a membrane matrix with varied concentrations (0 to 1.5 wt %). PSF nanocomposite membranes are prepared via a nonsolvent-induced phase-separation process. The results show an enhancement in hydrophilicity, porosity, and permeability with respect to the modified nanocomposite membranes because of oxygen-rich species in the membrane matrix, which increases affinity toward water. It was also found that the modified membranes display remarkably greater pure water flux (PWF) (220 L/m2 h), higher Congo red rejection coefficient (99.86%), higher humic acid removal (99.81%), higher fouling resistance, and a significant flux recovery ratio (FRR) (88%) when tested with bovine serum albumin protein when compared to a bare PSF membrane (30 L/m2 h PWF and 35% FRR). This is because the addition of MnCo2O4 nanoparticles into the polymeric casting solution yielded tighter PSF membranes with a denser skin layer and greater selectivity. Thus, the enhanced permeability, greater rejection coefficient, and antifouling properties show the promising potential of the fabricated PSF-spinel nanostructured membrane to be utilized in membrane technology for wastewater treatment.

Nitrogenated Graphene Oxide-Decorated Metal Sulfides for Better Antifouling and Dye Removal.

Nitrogenated graphene oxide-decorated copper sulfide nanocomposites (Cu x S-NrGO, where x = 1 and 2) are designed to be incorporated in polysulfone (PSF) membranes for effective fouling resistance of PSF membranes and their dye removal capacity. The developed membranes possess more hydrophilicity and an enhancement in pure water flux (PWF). Also, the highest bovine serum albumin (BSA) rejection of 89% was observed when compared to membranes with pristine PSF (5 L/m2 h PWF and 88% BSA rejection) and CuS-incorporated PSF membranes (14 L/m2 h PWF and 83% BSA rejection) because of N doping and enhanced permeability. It is also found that the Cu x S-NrGO-incorporated PSF membranes exhibited a significantly higher fouling resistance, a larger permeate flux recovery ratio (FRR) of nearly 82%, and a congo red dye rejection of 93%. Cu x S-NrGO nanoparticles thus demonstrate the potential efficacy of enhancing the hydrophilicity, leading to a better flux, dye removal capacity, and antifouling capacity with a very high FRR value of 82% because of a strong interaction between the N-active sites of the NrGO, Cu x S, and polysulfone matrix, and negligible leaching of nanoparticles is observed.

SiO2/Al2O3/C grafted 3-n propylpyridinium silsesquioxane chloride-based non-enzymatic electrochemical sensor for determination of carcinogenic nitrite in food products.

The excessive uptake of nitrite is perilous and detrimental for human health that prone to cancer disease. Herein, described the synthesis of SiO2/Al2O3/C material through the sol-gel procedure followed by grafting with 3-n propylpyridinium silsesquioxane chloride organic ligand for enhancing electrochemical activity. H-NMR, 13C NMR, and 29Si studies were performed for confirmation of surface functionalization through the grafting technique. The surface morphology was evaluated through SEM and TEM techniques. The material showed an irregular and flakes-like structure that exhibited more compactness and conglomerate structure with no segregation in phase was observed after grafting. The elemental composition was confirmed from EDX analysis. The electrochemical measurements were performed with cyclic voltammetry, electrochemical impedance spectroscopy (EIS), and chronoamperometry. The prepared hybrid inorganic-organic composite Si/C/Al/SiPy+Cl- was applied for the modification of the glassy carbon (GC) electrode and assessed as a sensor for nitrite determination. The sensor showed the low limit of detection (0.01 µM), low limit of quantification (0.08 µM), wide linear response range (0.2-280 µM), and high sensitivity (410 µA·µM-1). It gave a quick response time of <1 s in the presence of 70 µM nitrite. The fabricated sensor showed high sensitivity, chemical stability, and insignificant interference from co-existing species present in sausage meat and food industry discharges. The repeatability of the sensor was evaluated as 2.5 % R.S.D.; for n = 10 at 50 µM nitrite.

Ag nanoparticle-decorated chitosan/SrSnO3 nanocomposite for ultrafast elimination of antibiotic linezolid and methylene blue.

Effective design of ultrafast new-generation photocatalysts is a challenging task that requires highly dedicated efforts. This research focused on the development and design of ultrafast smart ternary photocatalysts containing SrSnO3 nanostructures in conjugation with chitosan (CTSN) and silver (Ag) nanoparticles by a very simple and straightforward methodology. Modern analytical tools such as FESEM, TEM, XRD, XPS, FTIR, and UV-Vis spectroscopy were employed to characterize the synthesized nanostructures. XRD and XPS analysis confirmed the successful creation of ternary organization among the Ag, CTSN, and SrSnO3. The TEM images clearly confirmed that CTSN possessed overlapping micron-sized sheets with a layered morphology, whereas the undoped SrSnO3 particles exhibited spherical and elongated shapes and particle sizes ranging from 20 to 80 nm. These particles were produced in high density with homogeneously distributed Ag nanoparticles (4-15 nm). The bandgap energy (Eg) for bare SrSnO3, CTSN/SrSnO3, and Ag@CTSN/SrSnO3 nanocomposites was found to be 4.0, 3.94, and 3.7 eV, respectively. The photocatalytic efficiencies of all newly created photocatalysts were evaluated by considering an antibiotic linezolid drug and methylene blue (MB) dye molecule as target analytes. Among all investigated samples, the Ag@CTSN/SrSnO3 photocatalyst was found to be highly superior, with ultrafast removal of the linezolid drug at 96.02% within 25 min and almost total removal of the MB dye in just 12 min under UV light irradiation. The Ag@CTSN/SrSnO3 photocatalyst exhibited removal rate that was 3.36 times faster than that of bare SrSnO3. The present report delivers a highly promising, extremely efficient, and very simple, straightforward treatment methodology for the effective destruction of lethal and notorious pollutants, enabling the appropriate management of current environmental concerns.

Si/SiO2/Al2O3 Supported Growth of CNT Forest for the Production of La/ZnO/CNT Photocatalyst for Hydrogen Production.

The use of ZnO as a photocatalyst with a reduced recombination rate of charge carriers and maximum visible light harvesting remains a challenge for researchers. Herein, we designed and synthesized a unique La/ZnO/CNTs heterojunction system via a sol-gel method to evaluate its photocatalytic performance for hydrogen evolution. A ferrocene powder catalyst was tested for the production of CNT forests over Si/SiO2/Al2O3 substrate. A chemical vapor deposition (CVD) route was followed for the forest growth of CNTs. The La/ZnO/CNTs composite showed improved photocatalytic efficiency towards hydrogen evolution (184.8 mmol/h) in contrast to 10.2 mmol/h of pristine ZnO. The characterization results show that promoted photocatalytic activity over La/ZnO/NTs is attributed to the spatial separation of the charge carriers and extended optical absorption towards the visible light spectrum. The optimum photocatalyst shows a 16 h cycle performance for hydrogen evolution. The H2 evolution rate under visible light illumination reached 10.2 mmol/h, 145.9 mmol/h and 184.8 mmol/h over ZnO, La/ZnO and La/ZnO/CNTs, respectively. Among the prepared photocatalysts, ZnO showed the lowest H2 evolution rate due to the fast recombination of electron-hole pairs than heterojunction photocatalysts. This research paves the way for the development of ZnO and CNT-based photocatalysts with a wide optical response and reduced charge carrier recombinations.