Development of quinoline-based heteroatom polybenzoxazines reinforced graphitic carbon nitride (GCN) carbonisation composites for emerging supercapacitor applications.

The current research described in this paper, focuses on the development of a new quinoline-based Mannich-type benzoxazine and its use to obtain advanced carbonisation materials with a high energy storage capacity. Based on this, a quinoline-based benzoxazine monomer (Q-xda) was synthesised by a reaction between 8-hydroxyquinoline, xylylenediamine and paraformaldehyde, and it is characterised by FT-IR and 1H-NMR spectroscopy. Composites were prepared from the benzoxazine and variable weight percentages of graphitic carbon nitride (GCN) (i.e., 5, 10, and 15 wt%). The oxazine ring-opening curing process of the polybenzoxazine composites, and its subsequent pyrolysis reaction was performed; and their chemical structures were confirmed using FT-IR spectroscopy. Also, the thermal and morphological characteristics of the composites were evaluated by XRD, thermogravimetric analysis (TGA), and SEM analyses. According to the results of the thermal experiments, adding GCN reinforcement significantly increased the thermal stability and char yield of the resultant composites. Electrochemical, and hydrophobic investigations were also carried out, and the results of these suggesting that the composites reinforced with 15 wt% GCN exhibit the highest dielectric constant (high κ = 10.2) and contact angle (145°). However, all the crosslinked composites demonstrated a remarkable electrochemical performance as pseudocapacitors. The resulting poly(Q-xda) + 15 wt% GCN electrodes showed a higher capacitance and a lower transferred charge resistance (i.e., 370 F g-1 at 6 A g-1 and 20.8 Ω) than the poly(Q-xda) electrode (i.e., 216 F g-1 at 6 A g-1 and 26.0 Ω). In addition, the poly(Q-xda) + 15% GCN exhibited a cycling efficiency of 96.2% even after 2000 cycles. From these results, it can be concluded that the constructed electrodes perform well in electrochemical operations.

A Quick, Highly Selective and Sensitive Colorimetric and Fluorimetric Sensor for Cyanide Ion.

A newly developed diindolium moiety has been synthesized and structurally investigated by employing a number of spectroscopic methods like NMR and HRMS in order to serve as a cyanide sensor DI. The interaction between DI and the CN- ion causes a noticeable color shift from pink to colorless, making it easy to detect CN- ions with the naked eye. Besides, the sensor exhibited fluorescence color change from orange to light blue under UV lamp. Sensor DI has remarkable selectivity and sensitivity in distinguishing between CN- and a wide range of interfering anions. The sensing mechanism of sensor DI towards CN- ion involves the nucleophilic addition process of CN- to the electron deficient indolium moiety. The detection limit of cyanide ion by sensor DI is calculated to be 1.4 × 10- 7 M by UV-visible and 8.2 × 10- 8 M by fluorescence technique which are lower than the limit set by WHO. The application of sensor DI for cyanide ion is utilized by making test kit and by taking different sources of water to test the presence of cyanide ion.

Ocean carbon emission prediction and management measures based on artificial intelligence remote sensing estimation in the context of carbon neutrality.

With rapid economic development, the gradual deterioration of the natural environment has posed unprecedented challenges to human social civilization. The marine economy, as an important part of economic development, is the breakthrough of economic transformation for many coastal countries. Additionally, green development and environmental impact assessment have become the focus of research in these countries. This study employs remote sensing technology, an efficient observational method, to significantly enhance the efficiency of ocean information observation. It investigates ocean carbon emissions within the framework of carbon neutrality. First, we identified the ships along the coastline based on marine remote sensing information through the YOLO (you only look once) framework. Second, we applied the LSTM (long short-term memory) method to combine the target identification results and the historical data of carbon emissions to complete the corresponding carbon emission data fitting. Finally, carbon emission data from the past three years in the offshore area of Dalian were used to make accurate predictions. The results suggested that the recognition rate of the proposed target detection method could reach 88%, and the LSTM method has shown the best performance in terms of absolute error for the subsequent short-term carbon emission prediction. This framework not only provides essential technical support for analyzing remote sensing information within the context of carbon neutrality but also introduces innovative insights for carbon emission prediction.

Comparative Study for Spectrofluorimetric Determination of Ambroxol Hydrochloride Using Aluminum Metal Transfer Chelation Complex and Biogenic Synthesis of Aluminum Oxide Nanoparticles Using Lavandula spica Flowers Extract.

The existing study pronounces two newly developed spectrofluorimetric probes for the assay of ambroxol hydrochloride in its authentic and commercial formulations using an aluminum chelating complex and a biogenically mediated and synthesized aluminum oxide nanoparticles (Al2O3NPs) from Lavandula spica flower extract. The first probe is based on the formation of an aluminum charge transfer complex. However, the second probe is based on the effect of the unique optical characteristics of Al2O3NPs in the enhancement of fluorescence detection. The biogenically synthesized Al2O3NPs were confirmed using various spectroscopic and microscopic investigations. The fluorescence detections in the two probes were measured at a λex of 260 and 244 and a λem of 460 and 369 nm for the two suggested probes, respectively. The findings showed that the fluorescence intensity (FI) covered linear concentration ranges of 0.1-200 ng mL-1 and 1.0-100 ng mL-1 with a regression of ˃0.999 for AMH-Al2O3NPs-SDS and AMH-Al(NO3)3-SDS, respectively. The lower detection and quantification limits were evaluated and found to be 0.04 and 0.1 ng mL-1 and 0.7 and 0.1 ng/mL-1 for the abovementioned fluorescence probes, respectively. The two suggested probes were successfully applied for the assay of ambroxol hydrochloride (AMH) with excellent percentage recoveries of 99.65% and 99.85%, respectively. Excipients such as glycerol and benzoic acid used as additives in pharmaceutical preparations, several common cations, and amino acids, as well as sugars, were all found to have no interference with the approach.

Detection of trizole contaminated waste water using biocatalyst and effective biodegradation potential of flubendiamide.

Flubendiamide is a new class of chemical pesticide with broad spectrum activity against lepidopteran pests. Due to limited approach and high specificity towards various non targeted organisms, the unrestricted application of this pesticide as a prominent alternate for organochlorine and organophosphate pesticides, causing serious environmental pollution. In this study, wastewater was used for the determination of microbial strains and pesticide degrading fungi. Microbial population and flubendiamide resistant fungal strains were characterized using enriched medium. Aerobic bacteria (6.38 ± 0.23 log CFU/mL), nitrifying bacteria (2.73 ± 0.31 CFU/mL), Lactobaillus (0.72 ± 0.03 log CFU/mL), actinomycetes (5.36 ± 0.27 log CFU/mL) and fungi (4.79 ± 0.22 log CFU/mL) were detected. The prominent fungi genera were, Fusarium, Trichoderma, Cladophialophora, Paecilomyces, Talaromyces, Penicillium, Aspergillus, Candida, Phyllosticta, Mycosphaerella, Ochroconis, and Mucor. Minimum inhibitory concentration of the rapidly growing organism (FR04) revealed its ability to tolerate up to 1250 mg/L flubendiamide concentration. Morphological, biochemical and molecular analysis revealed that the strain was Aspergillus terreus FR04. The residual pesticide was detected using a High Performance Liquid Chromatography (HPLC). High performance liquid chromatography analysis revealed that 89 ± 1.9% pesticide removal efficiency was observed in strain FR04 at optimized culture conditions (96 h, pH 6.5, 30 °C and 300 mg/L pesticide concentration). The strain FR04 degraded pollutants from the wastewater and improved water quality. A. terreu sFR04 is an indigenous fungus and has the ability to degrade trizole pesticides from the wastewater significantly.

Reduction of multiple antibiotics from the waste water using coated glutathione S-transferase producing biocatalyst.

Oxytetracycline is widely used in veterinary and human medicine. It has been detected in wastewater from pharmaceuticals, hospitals and domestic wastewater. In recent years, much more attention has been directed towards glutathione transferases (GSTs) because of their bio-transforming ability of antibiotics. In this study, 19 Lactobacillus strains were initially screened for the production of GSTs and five strains were selected for biotransformation of oxytetracycline. Among the strains, L. fermentum LA6 improved oxytetracyline degradation than other strains. It was subjected to optimize GST production and optimum growth was achieved after 24 h incubation at 32 ± 2 °C and 200 mg/L initial oxytetracycline concentration. The biocatalyst was immobilized and antibiotic degradation efficiency was analyzed. The immobilized culture of L. fermentum LA6 improved biodegradation of oxytetracycline in the wastewater. At 50 mg/L initial antibiotic concentration, 53.2 ± 2.8% oxytetracycline degradation was achieved, however, it improved at 200 mg/L antibiotic concentration in the culture medium (89.1 ± 4.3%) after 24 h. The chemical oxygen demand (COD) of the wastewater decreased significantly after treatment. At 200 mg/L oxytetracycline concentration, COD removal was considerably high (93.6 ± 5.3 mg/L) than 150 mg/L oxytetracycline concentration in the medium. Antibiotic removal efficiency in immobilized form revealed that this method is highly suitable for the removal of antibiotics from the wastewater.

Structure, morphology and modelling studies of polyvinylalcohol nanocomposites reinforced with nickel oxide nanoparticles and graphene quantum dots.

Nickel oxide (NiO) nanoparticles (NPs) and graphene quantum dots (GQDs) reinforced polyvinyl alcohol (PVA) nanocomposite films were prepared using a solution casting technique. The physicochemical characteristics of PVA/NiO/GQDs (PNG) nanocomposite films were studied using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM). The obtained PNG nanocomposite films showed good mechanical flexibility and improved tensile strength. The influence of nanofiller concentrations on PNG nanocomposite film. The obtained results demonstrate an increase in the activation energy (Ea) up to PNG3 upon increasing the GQDs concentration and thereafter, its decreases. The fundamental interactions of the constituents of PNG nanocomposite film were investigated using density functional theory (DFT). This study on electronic structure reveals that the PVA model indirectly interacts with GQDs through the NiO model. This configuration is favoured in terms of interaction energy (-78 kJ/mol) compared to the one in which PVA interacts directly with the GQDs model.

Photocatalytic effect of CuO nanoparticles flower-like 3D nanostructures under visible light irradiation with the degradation of methylene blue (MB) dye for environmental application.

The present research work focuses on preparing 3D transition metal doped copper oxide nanostructures through sonication method and to investigate the effect of doping different transition metal into copper oxide (CuO) on the basic properties of CuO nanoparticles and, to study the photocatalytic behaviour of the doped CuO samples. The morphological studies performed with the help of SEM revealed the formation of flower like CuO 3D nanostructures for all the doped samples. The slight shift in the position of peaks in the x-ray diffraction (XRD) pattern confirms that doping has been successfully done into CuO. Also, the sharp diffraction peaks suggest the polycrystalline nature of the sample with monoclinic structure. The UV-vis absorption analysis reveals a bandgap of 2.26, 2.12 and 2.15 eV for the CuO samples doped with nickel, zinc, and iron respectively via Tauc plot. The photocatalytic performance of the samples tested through the degradation of methylene blue (MB) dye suggests that samples doped with Zn shows better degradation. Thus, it is evident that the morphology and the optical properties of the CuO can be tailored by doping transition metal into it.

Adsorption of copper and nickel by using sawdust chitosan nanocomposite beads - A kinetic and thermodynamic study.

The adsorption behavior of biomaterial activated Sawdust-Chitosan nanocomposite beads (SDNCB) powder was investigated along with synthesis and experimental techniques approaches to study the removal efficiency of some heavy metal ions including Ni (II) and Cu (II) ions from aqueous solutions by assessing the surface-modified activated carbon by the cost-effective non-conventional method. Structural analysis of the entitled compound was evaluated by the PXRD techniques and its surface morphology was inferred by the following techniques: TEM, EDAX. The behavior of the functional group presents in the compound was discussed using the FTIR technique. Such parameters like dosage, pH, time, temperature, and initial concentration of copper and nickel were associated with this to examine the effect of adsorption of heavy elements that exist in the portable solution. Further, the cellulose and chitosan beads complex material have an appropriate surface area, it demonstrated metal ions removal efficiency was more appreciable due to the action of activated carbon, where this showed fast rate sorption kinetics due to strong involvement of Cu+ & Ni+ towards cellulose and chitosan's functional groups in the bio composite. The isotherm model so-called Langmuir, Freundlich, and Temkin model was utilized to plot the experimental adsorption dataset to infer the maximum adsorption capacity. Based on this model, the adsorption properties of the beads treated compound was determined by plotting the graphs in which sorption intensity (n) which implies expected sorption, and the correlation value are 1.989, 0.998, and 0,981 respectively.

Facile fabrication of bifunctional SnO-NiO heteromixture for efficient electrocatalytic urea and water oxidation in urea-rich waste water.

Heterostructured transition metal oxide hybrid have more attention in energy saving and environmental related field due to their higher electro-catalytic activity. In this work, we demonstrated SnO decorated with NiO nanocrystal electrocatalyst is successfully synthesized through solvothermal method and well characterized by scanning electron microscope, transmission electron microscope, X-ray diffraction and X-ray photoelectron spectroscopy. Physical characterizations confirm that spherical shape of SnO nanoparticles are homogeneously dispersed on the surface of NiO. The kinetic study of catalytic performance towards urea oxidation reaction were measured by liner sweep voltammetry and chronoamprometry. As proposed catalyst to facilitate the rate of urea oxidation reaction can increase by SnO doped NiO catalyst. The urea oxidation on SnO-NiO nanostructured modified electrode exhibits lower onset potential of 1.12 V and enhancement of current with tafel slope of 150 mV dec-1. The obtained results demonstrated the synthesized SnO-NiO anode material could be promising electrode for urea-rich containing wastewater remediation and hydrogen production from wastewater.

Improved photocatalytic activity for degradation of textile dyeing waste water and thiazine dyes using PbWO4 nanoparticles synthesized by co-precipitation method.

The coloured dyes released from the textile industrial effluents into water resources cause non-aesthetic pollution and aquatic life toxicity. Thus textile waste water treatment has been studied globally for many years. Photocatalytic properties of lead tungstate (PbWO4) nanoparticles (NPs) were analyzed for thiazine dyes and textile waste water under ultraviolet light conditions. XRD result showed the tetragonal scheelite structure of PbWO4 NPs. The crystallinity of the sample was confirmed from the SAED and XRD pattern. The existence of stretch vibration of Pb-O and O-W-O confirmed from FTIR results. EDAX displays optical absorption signals of Pb, W and O, and confirm the formation of PbWO4. Optical studies reveal that the band gap of the obtained nanoparticles increases with respect to their bulk counterparts that may be attributed to reduction in particle size. TEM images of PbWO4 powder consists of hexagonal particles and relatively uniform and smooth surface rod shaped prism-like structures. The photocatalytic activity of the prepared nanoparticles was analyzed through the degradation of textile waste water under UV light irradiation. The photocatalytic reaction rate constant was found to be 0.014/min. The small sized PbWO4 particles can adsorb more OH groups and oxidatively degrade the pollutants in the textile waste water.

Evaluating the detection efficacy of advanced bimetallic plasmonic nanoparticles for heavy metals, hazardous materials and pesticides of leachate in contaminated groundwater.

During the decomposition of trashes, leachate is created and leaching is gradually pollutes the surface and groundwater. Thus, the most severe ecological impact is the risk of ground water pollution because of collection of leachate from unlined insecure landfills. Due to the low biodegradable organic strength, irregular productivity and composition, the environmentally neglected landfill leachate treatment is challenging. This work was conducted on a synthetically effective bimetallic surface enhanced Raman spectroscopic (SERS) nanosensor by gold/silver-bimetallic nanoparticles (Au/Ag-NPs), and used for the specific detection of municipal solid waste (MSW) landfill leachate in groundwater. The optical study of Au/Ag-NPs led to reflections from Ag cores and small Au shells. The structural studies represent the FCC structure of Au/Ag-NPs. The core-shell nanocrevice NPs with particle size of 23 nm played an important role with plasmonic behaviour enhances the electromagnetic excitation to achieve SERS detection and plasmonic photocatalysis. Thus, obtained results clearly show that Au was successfully added to Ag-NPs, and its existence can also be confirmed by energy dispersive spectroscopy (EDAX). The prepared SERS based sensors have the potential to detect aromatic hydrocarbon, pesticides and heavy metals from environmentally ignored MSW landfill leachate. In general, the application of this new synergetic strategy of the photocatalytic degradation of leachate was irradiated by visible wavelength with the rate constant of 0.0036/min, 0.0047/min and 0.005/min by Ag-NPs, Au-NPs and Au/Ag-NPs respectively. Overall, this is the only study achieved efficiently with photocatalytic degradation and SERS detection of environmentally ignored real sample (leachate) to make pollutant free homeland aquifers.

Functionalization of gold nanoparticles by ß-cyclodextrin as a probe for the detection of heavy metals in water and photocatalytic degradation of textile dye.

Gold nanoparticles (AuNPs) and AuNPs functionalized by ß-cyclodextrin (ß-CD/AuNPs) were prepared successfully through chemical reduction method. The structural, morphological, optical, compositional and vibrational studies for the AuNPs and ß-CD/AuNPs were carried out. Functionalization of AuNPs by ß-CD was confirmed with FT-IR results. The UV-visible absorption spectra exhibit a red-shift with decreasing average particle size. This sustains the enhancement in surface area (SA) to volume (V) ratio that is one of the peculiar characteristics of nanoparticles. TEM results show that ß-CD/AuNPs formed were monodispersed and self assembled. Also it shows a decrease in average particle size and improved distribution. The use of ß-CD in the synthesis of AuNPs are revealed not only create uniform small sized nanoparticles but these water soluble nanoparticles have very good antibacterial action by inhibiting the growth of bacteria commonly found in water and sensing activity for sensing the concentration of toxic metals in water. The sensitivity of the system towards copper (Cu) concentration was found as 1.788/mM for ß-CD/AuNPs and 1.333/mM for AuNPs. The photocatalytic action of the obtained nanoparticles increases with decreasing average particle size. The kapp value of this photocatalytic degradation of textile dyeing waste water in presence of AuNPs was 0.002/min and ß-CD/AuNPs was 0.005/min. This is a non-toxic and eco-friendly approach.

Green sporopollenin supported cyanocalixarene based magnetic adsorbent for pesticides removal from water: Kinetic and equilibrium studies.

In this study, magnetic sporopollenin supported cyanocalixarene (MSP-CyCalix) nanocomposite was synthesized and introduced as an adsorbent material for the removal of pesticides from aqueous media. MSP-CyCalix was characterized by different analytical techniques FTIR, SEM, EDX, BET, VSMand TEM. Chlorpyrifos and hexaconazole pesticides were chosen as model analytes solutions for testing the adsorption efficiency of MSP-CyCalix adsorbent. The adsorption results showed that the incorporated cyano functional groups significantly increased the chemical reactivity and adsorption capacity for pesticides. To obtain the highest possible performance, experimental parameters such as pH, salt, dosage and time were optimized. Adsorption kinetics and isotherms models showed that pesticide adsorption process was well fitted with the pseudo-second-order and Langmuir models with a maximum adsorption capacity of 13.88 mg g-1 and 12.34 mg g-1 and a removal efficiency of >90% for both pesticides. Lastly, MSP-CyCalix maintained a removal efficiency of >80% for ten cycles and 60% after the eleventh cycles of usage. The results proved that MSP-CyCalix nanocomposite can be used as an efficient adsorbent for the removal of pesticide residues from water.

Selective electrochemical detection of antidepressant drug imipramine in blood serum and urine samples using an antimony telluride-graphite nanofiber electrode.

A high-performance imipramine (IMPR) sensor has been developed  based on metal chalcogenide-carbon composite materials. The antimony telluride-graphite nanofiber (Sb2Te3-GNF, hereafter SBT-GNF) composite was synthesized by the hydrothermal method and confirmed by X-ray powder diffraction (XRD) pattern. The morphology, crystalline lattice, and chemical states were characterized by HRTEM, SAED, and XPS analysis. The characterizations confirmed the formation of an effective composite, SBT-GNF. The SBT-GNF was fabricated as a disposable sensor electrode with a screen-printed carbon electrode (SPCE) and examined for the detection of IMPR by differential pulse voltammetry (DPV). The electroanalytical results of SBT-GNF are compared with the SBT and GNF, and the rational design of effective composite is discussed. SBT-GNF/SPCE showed a good linear range (0.01­51.8 µM), sensitivity (1.35 ± 0.1 µA µM-1 cm-2), and low LOD (4 ± 2 nM). Moreover, the SBT-GNF/SPCE revealed high selectivity and high tolerance limit against potential interfering compounds in blood serum and urine samples. Therefore, this electrochemical sensor can be applicable for the detection of tricyclic antidepressant drug IMPR in clinical and pharmaceutical analysis.

An eco-friendly low-temperature synthetic approach towards micro-pebble-structured GO@SrTiO3 nanocomposites for the detection of 2,4,6-trichlorophenol in environmental samples.

The low-temperature synthesis of the graphene oxide-wrapped perovskite-type strontium titanate nanocomposites (GO@SrTiO3-NC) is reported for the electrochemical sensing of organochlorine pesticide 2,4,6-trichlorophenol (TCP) detection. The as-prepared GO@SrTiO3 nanocomposites provide a large surface area, excellent conductivity, and active sites, which are more favorable to the catalysis of TCP. The synergistic effect between the GO and the perovskite SrTiO3 results in the extended working range of 0.01 to 1.47 and 1.47 to 434.4 µM with a very low detection limit of 3.21 nM towards TCP detection. Moreover, the prepared sensor possessed good selectivity and long-term stability. Finally, the practical applicability of the sensor was tested in environmental samples of river water and soil, exhibiting adequate recovery values.

Exploring pH levels and environmental impacts on handwash products in Riyadh, Saudi Arabia: A cross-sectional study.

Background: The human skin, with a pH of 4 to 6, serves as a barrier against external pathogens. Alkaline handwash products (HWPs) can compromise this barrier and are widely used following the Coronavirus disease-2019 (COVID-19) pandemic. This study aims to determine the pH of a sample of HWPs in Riyadh, Saudi Arabia, and assess the effect of environmental factors on their pH. Methods: This is a cross-sectional, descriptive, observational study carried out in Riyadh, Saudi Arabia. The study involved a convenience sample of 33 liquid soaps, soap bars, and synthetic detergents (Syndets) from various brands. The pH of the handwash products was measured using laboratory-validated techniques. Data analysis was conducted using RStudio 2022 software. Results: Of the HWPs, 16 (48.5%) had a highly alkaline pH (≥10), while 14 (42.4%) had an acidic pH (4.0-6.9). Most liquid soaps were acidic (84.6%), with a mean pH of 5.9, whereas soap bars had a mean pH of 10.3. Syndets had a mean pH of 6.0. Conclusions: On average, liquid soaps and syndets offered a more physiological pH than soap bars. Liquid soaps were more affordable than synthetic detergents, making them a better value option among the three types of HWPs. Environmental factors such as exposure to hot weather did not have a significant impact on HWPs.

Simultaneous determination of bromoxynil and MCPA in commercial samples and raw materials using reversed phase high performance liquid chromatography.

This study encompasses a quick, efficient, repeatable and reproducible analytical method for simultaneous determination of Bromoxynil (3, 5-Dibromo-4-hydroxybenzonitrile) and MCPA (2-methyl-4-chlorophenoxyacetic acid) using RP-HPLC with UV-Detector. Bromoxynil + MCPA is one of the most selective post emergent herbicide formulations for the control of important broad leaf weeds infesting small grains (wheat, barley, oats, rye), conservation reserve program areas and grass grown for seed. Optimum weed control is achieved when Bromoxynil + MCPA is applied to actively growing weed seedlings. So, a simple, repeatable, reproducible and efficient simultaneous analytical method was developed for Bromoxynil + MCPA. The developed method was applied for the detection and quantitation of these pesticides in formulations and raw materials with excellent recoveries. It was validated according to ICH Guidelines with excellent linearity R2 = 0.992 for Bromoxynil and 0.998 for MCPA. For Bromoxynil, LOD = 1.57 mg/L and LOQ = 5.22 mg/L while for MCPA the LOD = 1.08 mg/L and LOQ = 3.62 mg/L was found. The proposed method has shown high precision (RSD %) 0.06% and 0.11% for Bromoxynil and MCPA respectively while the trueness has been calculated in terms of recovery percentage obtained as "mean value of Bromoxynil 99.53% and MCPA 100.10%" which is excellent under optimized conditions. For repeatability and reproducibility, five replicate readings of standard and sample were taken and had found within acceptable limits of relative standard deviation (RSD ≤ ± 2%). Finally, the robustness of the developed method was determined by changing flow rate and mobile phase ratios that has found within the permissible limits (% RSD NMT 1.5). So, the proposed analytical method has found to be more precise, valid and accurate at commercial scale.

Structural, Optical, Electrical and Photocatalytic Investigation of n-Type Zn2+-Doped α-Bi2O3 Nanoparticles for Optoelectronics Applications.

Herein, n-type pure and Zn2+-doped monoclinic bismuth oxide nanoparticles were synthesized by the citrate sol-gel method. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), photoluminescence (PL) analysis, ultraviolet-visible (UV-vis) spectroscopy, and Hall effect measurements were used to study the effect of Zn2+ on the structural, optical, and electrical properties of nanoparticles. XRD revealed the monoclinic stable phase (α-Bi2O3) of all synthesized samples and the crystallite size of nanoparticles increased with increasing concentration of dopant. Optical analysis illustrated the red shift of absorption edge and blue shift of band gap with increasing concentration of dopant. Hall Effect measurements showed improved values (2.79 × 10-5 S cm-1 and 6.89 cm2/V·s) of conductivity and mobility, respectively, for Zn2+-doped α-Bi2O3 nanoparticles. The tuned optical band gap and improved electrical properties make Zn2+-doped α-Bi2O3 nanostructures promising candidates for optoelectronic devices. The degradation of methylene blue (MB, organic dye) in pure and zinc-doped α-Bi2O3 was investigated under solar irradiation. The optimum doping level of zinc (4.5% Zn2+-doped α-Bi2O3) reveals the attractive photocatalytic activity of α-Bi2O3 nanostructures due to electron trapping and detrapping for solar cells.

3D/2D-Bismuth Oxybromide Spheres with Selenium-Doped Graphitic Carbon Nitride Sheets: An Efficient Electrocatalyst for the Detection of Arsenic Drug Roxarsone.

Heavy metals are crucial carcinogenic agents threatening the environment and living habituates. Among them, arsenic (As) is an important metalloid that is categorized as a group I toxic carcinogen. Roxarsone (RX) is an organoarsenic antibiotic compound primarily used as a veterinarian drug and growth promoter for poultry animals. The extensive usage of RX increased the accumulation of As in living beings and the ecosystem. Therefore, we have prepared an electrochemical sensor based on 3D bismuth oxybromide with 2D selenium-doped graphitic carbon nitride (BOB/SCN) electrocatalyst for the rapid detection of RX. The elemental and structural details were thoroughly investigated with several spectroscopic techniques. The electrochemical properties were measured by impedance and voltammetric measurements. The electrocatalytic behavior toward the RX was estimated with different voltammetric methods. Therefore, our BOB/SCN-based electrochemical sensor demonstrated a low detection limit (2.3 nM), low quantification value (7.7 nM), optimal sensitivity (0.675 µA µM-1 cm-2), and good linear ranges (0.01-77 and 77-857 µM). Additionally, this sensor showed good electrochemical performance and was applied to monitor the RX in various real samples with remarkable recoveries. Based on these results, our BOB/SCN sensor is a promising electrochemical platform for determining RX.