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The electrical characterization of polyvinylidene fluoride (PVDF)/polyvinyl chloride (PVC) composites after scattering by gold nanoparticles (AuNPs) has been studied by a one-way laser ablation process. AuNPs@PVDF/PVC nanocomposites were synthesized in films formed via traditional casting technique. The electrical conductivity of AuNPs@PVDF/PVC films was also studied. FT-IR indicated that adding AuNPs to PVDF/PVC confirmed the interaction and complexation between a PVDF/PVC composite and AuNPs. UV–Vis results confirmed the presence of surface plasmon resonance of AuNPs at 519 nm. The indirect optical bandgap was decreased by increasing the scattered AuNPs in the PVDF/PVC from 2.26 eV for pure PVDF/PVC to 1.61 eV for AuNPs@PVDF/PVC at 20 min ablation time. The addition of AuNPs to a PVDF/PVC composite enhances the conductivity due to the increase in the number of ions resulting from increasing ablation time.

Blend of Polyvinyl Alcohol/Chitosan doped by selenium nanoparticles was synthesized via one step laser ablation route to improve the antibacterial activity of the pure blend. The effect of two concentrations of selenium on the optical, structural, and morphological properties of the synthesized PVA/Chitosan/SeNPs nanocomposite films were characterized. The antibacterial activity of the prepared samples has been investigated. XRD and FTIR-ATR results confirm the interaction between selenium nanoparticles and PVA/Chitosan. Furthermore, the change in the values of optical energy band gap confirms the scattered selenium nanoparticles into PVA/Chitosan film. The activity index shows an increase in the diameter zone with increasing the concentration of selenium nanoparticles content. The results confirmed that doping of selenium nanoparticles to (PVA/Chitosan) lead to increase the antibacterial activity of the pure PVA/Chitosan blend that suggests this nanocomposite could be used in several antimicrobial applications.

This article attempt to synthesis titanium dioxide (TiO2) doped zinc oxide (ZnO) composite via Pulsed Laser Ablation in Liquids (PLAL) and study its antibacterial properties. The structure, optical, morphological of the prepared composite have been investigated via various technique. FT-IR results confirm existence of TiO2 doped ZnO. XRD measurements approved the enhanced crystallinity ZnO after doped by TiO2 via PLAL technique. The optical transmittance was enhanced from 78.6% of pure ZnO to 92.3% for TiO2 doped ZnO. TEM images of ZnO showed an obvious elongated rod-like shapes that were rectangular or hexagonal and spherical particles. Moreover, the cell viability has been studied for the papered pure ZnO and TiO2 doped ZnO. The minimum cell viability ratio was about 81.4 ± 4.2% for pure ZnO and was increased to 91.6 ± 5.1% for TiO2 doped ZnO. The antibacterial activity of the samples that measured via MIZ approved that the TiO2 doped ZnO make a raise in the activity index. It was suggested that TiO2 doped ZnO can be used in many antimicrobial application.

Atrazine (ATZ) is a known herbicide used in agriculture and caused many concerns according to its toxicity. Herein, we have prepared NiCo2O4 nanorods that can work as a photocatalyst under visible light exposure by Ag loading through a simple route. The characterizations revealed the role of Ag for improving the structural, optical and optoelectronic properties of the produced photocatalyst. The Ag loading with 5 wt% confirms the minimization of the bandgap from 3.6 down to 2.57 eV with enhanced visible light absorption and sustaining the magnetic properties. The Ag/NiCo2O4 nanorods showed a superior photodegradation of ATZ within 20 min at 2.0 g L–1 with excellent recyclability. The enhancement of the photocatalytic activity is referred to the local surface plasmon resonance of Ag-loaded photocatalyst. This reduces the electron-hole recombination and outperforms the unloaded sample. This work is highlighting the application of magnetically separable spinel photocatalysts for the removal of herbicides and water remediation.

A new water-insoluble organic dye, namely, 2-((10-decyl-10H-phenothiazin-3-yl)methylene)malononitrile, was synthesized and fully characterized. It was envisioned that photocatalytic decolourization of a dye-containing long chain would pave the way for the photocatalytic remediation of wastewater containing toxic hydrophobic organic pollutants. Two commercially available nanoparticles, ZnO and TiO2, were selected, and their photocatalytic decolourization of the dye from aqueous medium were compared. The black UV light irradiation of the colored samples in the presence of TiO2 (P25) or ZnO resulted in their decolourization and the photocatalytic activity observed for TiO2 (P25) was better than that of ZnO. The kinetic of decolourization indicated that the process was first-order from which the rate constant was calculated. Also, the effect of pHs on the kinetic of decolourization revealed a negligible effect, indicating that the pH, although it affects the catalysts but has no effect on the organic-based hydrophobic dye and thus no effect on the photocatalytic process. Keywords: Phenothiazine, Photocatalysis, Water-insoluble dye, Photocatalytic decolourization, TiO2, ZnO

The incorporation of tungsten trioxide (WO3) by various concentrations of graphitic carbon nitride (g-C3N4) was successfully studied. X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and Diffused Reflectance UV-Vis techniques were applied to investigate morphological and microstructure analysis, diffused reflectance optical properties, and photocatalysis measurements of WO3/g-C3N4 photocatalyst composite organic compounds. The photocatalytic activity of incorporating WO3 into g-C3N4 composite organic compounds was evaluated by the photodegradation of both Methylene Blue (MB) dye and phenol under visible-light irradiation. Due to the high purity of the studied heterojunction composite series, no observed diffraction peaks appeared when incorporating WO3 into g-C3N4 composite organic compounds. The particle size of the prepared composite organic compound photocatalysts revealed no evident influence through the increase in WO3 atoms from the SEM characteristic. The direct and indirect bandgap were recorded for different mole ratios of WO3/g-C3N4, and indicated no apparent impact on bandgap energy with increasing WO3 content in the composite photocatalyst. The composite photocatalysts’ properties better understand their photocatalytic activity degradations. The pseudo-first-order reaction constants (K) can be calculated by examining the kinetic photocatalytic activity.

Recently, nanofibers have come to be considered one of the sustainable routes with enormous applicability in different fields, such as wastewater treatment. Electrospun nanofibers can be fabricated from various materials, such as synthetic and natural polymers, and contribute to the synthesis of novel nanomaterials and nanocomposites. Therefore, they have promising properties, such as an interconnected porous structure, light weight, high porosity, and large surface area, and are easily modified with other polymeric materials or nanomaterials to enhance their suitability for specific applications. As such, this review surveys recent progress made in the use of electrospun nanofibers to purify polluted water, wherein the distinctive characteristics of this type of nanofiber are essential when using them to remove organic and inorganic pollutants from wastewater, as well as for oil/water (O/W) separation.

Electrospun techniques are promising and flexible technologies to fabricate ultrafine fiber/nanofiber materials from diverse materials with unique characteristics under optimum conditions. These fabricated fibers/nanofibers via electrospinning can be easily assembled into several shapes of three-dimensional (3D) structures and can be combined with other nanomaterials. Therefore, electrospun nanofibers, with their structural and functional advantages, have gained considerable attention from scientific communities as suitable candidates in biomedical fields, such as the regeneration of tissues and organs, where they can mimic the network structure of collagen fiber in its natural extracellular matrix(es). Due to these special features, electrospinning has been revolutionized as a successful technique to fabricate such nanomaterials from polymer media. Therefore, this review reports on recent progress in electrospun nanofibers and their applications in various biomedical fields, such as bone cell proliferation, nerve regeneration, and vascular tissue, and skin tissue, engineering. The functionalization of the fabricated electrospun nanofibers with different materials furnishes them with promising properties to enhance their employment in various fields of biomedical applications. Finally, we highlight the challenges and outlooks to improve and enhance the application of electrospun nanofibers in these applications.

Composite thin-film nanofiltration membranes were prepared by interfacial polymerization of trimesoyl chloride (TMC), polyvinyl pyrolidone (PVP) and montmorilonite (MMT) composite on the porous polyethersulfone (PES) membrane. The effect of preparation parameters were studied as; reaction time, PVP concentration and MMT content. The properties of the prepared composite thin film membranes were analyzed in terms of their chemical structure, surface morphological features, pure water contact angel, zeta potential, pure water permeation flux (PWP) and solutes rejections. The composite thin film membranes had smoother surfaces, different surface functionality and amphoteric surafce with point of zero charges within pH 7-7.5. The PWP was found to increase with increasing MMT content up to 0.10 wt. %. The rejection of crystal violet dye (CV) was studied using the prepared membranes, where the membrane with 0.5 % PVP, 0.10% MMT at reaction time 6 min showed PWP of 18.1 (L/m2.h.bar) and CV rejection of 80.01 %. The rejection of Na2SO4 and MgCl2 was found to increase with MMT content and reached 96% and 35.4 %, respectively. The steady state flux was decreased by 5% with increasing MMT content from 0.10 to 0.12 wt. % reflecting antifouling improvement with MMT.

Hybrid polymer films of polyvinyl pyrrolidone (PVP)/ polyvinyl alcohol (PVA) embedded with gradient levels of Bi-powder were prepared using a conventional solution casting process. X-ray diffraction (XRD), Fourier transform infrared spectroscopic (FT-IR), and Scanning electron microscope (SEM) techniques have been used to examine the micro/molecular structural and morphological of the synthesized flexible films. The XRD peak intensity and FTIR spectra of the PVA gradually decline as Bi-metal is introduced. In addition, filler changes the microstructure surface of the pure film. The modification in the microstructure leads to an enhancement in the optical characteristic of the blend films. The indirect allowed transition energy was calculated via Tauc's and ASF models. The decrease in the hybrid film’s bandgap (\({E}_{gi}^{opt}\)) returns to the localized states in the forbidden region, as illustrated by the Urbach energy (Eu) values. The optical absorption parameters, including absorption coefficient (α) and edge (Ee), have also been evaluated. The relation between the transition energy and the refractive index (n) was studied. The rise of Bi-metal concentrations leads to an improvement in the nonlinear (χ(3)) susceptibility and (n2) refractive parameters. The optical limiting characteristics (OLC) revealed that the higher concentration dopant films reduce the light transmission intensity. The results suggest that hybrid films are promising materials in a wide range of applications, especially optical devices, and optoelectronics.

In the current study, the effect of Au-decoration was investigated on the capability of a gallium nitride nano-tube (GaNNT) in detecting sulfonamide (SA) via the density functional B3LYP. The GaNNT had a weak interaction with SA with sensing response (SR) of roughly 4.3. The energy of adsorption (Ead) of SA decreased from −6.0 to −22.9 kcal/mol after an Au atom was decorated onto the surface of the GaNNT and also the SR increased to 98.1. At 298 K, SA was desorbed from the surface of this decorated nano-tube with the recovery time of 4.9 s. Ead of SA was reduced by the water solvent to −19.1 kcal/mol. Finally, the Au-decorated GaNNT was found to be a promising sensor to detect SA with high sensitivity.

In this study, the phosphazene chitosan derivative was manufactured and characterized. adsorption of molybdenum (Mo) from solutions using prepared working material as sorbent was examined. Nuclear magnetic resonance spectroscopy (1HNMR), Carbon-13 (13CNMR) nuclear magnetic resonance, Gas Chromatography–Mass Spectrometry (GC–MS), Phosphorus-31 nuclear magnetic resonance (31P-NMR), scanning electron microscopy (SEM), Brunauer–Emmett–Teller analysis (BET surface area) and Fourier-transform infrared spectroscopy (FTIR) were used to characterize and confirm the prepared adsorbent. Many variables, including pH of the aqueous solution, the amount of adsorbent dosed, initial concentration of Mo(VI), contact time, and temperature were examined using the batch adsorption technique. When Mo(VI) is exposed to foreign ions, its desorption behavior changes. (Cr6+, Cl−, Co2+, Fe3+, and sulfate) were investigated. Cr6+ had a greater impact on the adsorption process in compared with other foreign ions. The maximum capability for Mo(VI) adsorption on the created adsorbent was 305.07 ± 2.36 mg/g, which was obtained at room temperature. The adsorption isotherms were best fitted with the Freundlich isotherm model. The kinetic data fitted well with the pseudo-second-order equation. The thermodynamic studies found that the adsorption was an exothermic and spontaneous process in nature.

A facial one-step synthesis procedure was applied to prepare porous sponge-like ceria (CeO2). The synthesis was performed by mixing cerium nitrate with citric acid, followed by thermal treatment. The produced solid material was characterized by several techniques, such as XRD, SEM, N2 sorption measurement, DR-UV-vis, and Raman spectroscopy. The characterization data showed that the nanoparticles of the porous ceria were formed with a three-dimensional pore system. Moreover, the measured surface area of the porous sample was eight times higher than the commercially available ceria. The photocatalytic performance of the porous ceria was investigated in two different applications under visible light illumination. The first was the decolorization of a methyl green aqueous solution, while the second was the photocatalytic elimination of a gaseous mixture consisting of five short-chain hydrocarbons (C1–C3). The obtained results showed that the photocatalytic activity of porous ceria was higher than that of the commercial sample. Finally, the recycling of porous ceria showed low deactivation (less than 9%) after four consecutive runs.

With the distribution of exploitable non-renewable energy resources, the use of lignocellulosic wastes to make bioethanol and biogas has drawn great attention from researchers. In our effort to find a potent cellulase-producing fungal strain, the fungus NAS51 was isolated from a sponge collected from the Red Sea, Jeddah, among eight isolates and selected as it displayed potent cellulolytic activity. The fungus was identified morphologically and genetically by sequencing its 18SrRNA gene as Aspergillus sp. NAS51. The cellulase activity of Aspergillus sp. NAS51 was optimized and maximum enzyme production was obtained at initial pH7, temp 30oC, incubation period 11 days, moisture content 70%, urea as a nitrogen source, and K2HPO4 (2g/L). The cellulase gene has been sequenced and the protein 3D structure was generated via in silico homology modeling. Determination of binding sites and biological annotations of the constructed protein was carried out via COACH and COFACTOR based on the I-TASSER structure prediction. To reach the maximum enzyme hydrolysis, the rice straw collected from Al-Ahsa, Kingdom of Saudi Arabia was pretreated with NaOH 1.5% to remove lignin and to enhance the saccharification process by cellulase enzyme. The saccharified product was measured using HPLC, fermented by S. cerevisiae and the bioethanol yield produced from the fermentation was 0.454 ml ethanol/g fermentable sugars.

A step-scheme (S-scheme) photocatalyst made of sulfurized graphitic carbon nitride/cobalt doped zinc ferrite (S-g-C

Organic polymers in the process of thermal degradation produce a lot of toxic fragments. In this work, we designed a new method of degradation of polymethylmethacrylate (PMMA) materials with aluminum triiodide nanoadditives (AlI

One of the exciting aspects of different nanomaterials in biomedical applications is the delivery of a wide range of anti-cancer drugs to mitigate their negative side effects via precise targeting of the tumor cells. In the present study, the DFT B3LYP/6-31G (d, p) level of theory was used to evaluate the capabilities of raw BC

A well-defined heterojunction among two dissimilar semiconductors exhibited enhanced photocatalytic performance owing to its capability for boosting the photoinduced electron/hole pair transportation. Therefore, designing and developing such heterojunctions using diverse semiconductor-based materials to enhance the photocatalytic ability employing various approaches have gained research attention. For this objective, g-C

Coal fly ash (CFA) is one of the major pollutants around the whole world. At the same time, incense stick ash (ISA) is another waste that is generated in huge amounts in Southeast Asia. Both of these wastes are rich in different types of minerals; for instance, CFA is rich in alumina, silica, and ferrous, while incense sticks ash is rich in calcium and silica. ISA has intermediate to trace amounts of ferrous, alumina, and magnesium. The addition of alkali-rich materials with high Al and Si-containing CFA helps in the formation of zeolites or geopolymers. So, in the current research work, the authors have prepared a CFA: ISA mixture in the ratio of 1:1, followed by mixing them with NaOH, CaOH2, and KOH in a dry state in a crucible. Further, all these mixtures were then calcined at 600 °C for six hours in a muffle furnace. Further, the developed products were analyzed by various sophisticated instruments for detailed information. Finally, the developed material’s potential was assessed for the remediation of malachite green from the aqueous solution by batch adsorption study. The developed adsorbents efficiently removed the dye from the aqueous solutions within one hour. The kinetic study revealed that the dye removal followed a pseudo-second-order reaction. Finally, the developed material was also assessed for its suitability as an adsorbent by observing the effect of leaching of potassium, aluminum, and silica from the adsorbent surface into the water systems. Such approaches will solve the problem of solid waste disposal arising from both the ashes.

Gold and Selenium ions have been incorporated into hydroxyapatite (HAP) using the co-precipitation technique at different contributions of Au(III). The obtained compositions were inspected via X-ray diffraction (XRD), Fourier transforms infrared (FTIR), and field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM). Structural parameters showed that Au content has a noticeable role in altering HAP lattice. TEM images display that the grain width decreased from 30 nm in 0.0Au/Se-HAP to 15 nm in 0.8Au/Se-HAP. The c/a ratio denoted a slight distortion in lattice after Au(III) contribution. Moreover, the roughness average increased from 26.3 nm reaching 32.4 nm for the lowest and the highest additional Au(III) contents. The compositions of 0.4Au/Se-HAP and 0.6Au/Se-HAP showed low crystallinity with surface defects, subsequently the highest percentage in cell viability. Furthermore, the indirect bandgaps become narrow with increasing additional Au(III) contribution starting from 6.45 to 6.40 eV. The refractive index shows a decreasing trend from 1.61 to 1.59 with increasing the Au(III) content. Cell viability starts from 94.0 ± 5% in 0.0Au/Se-HAP composition and increases gradually to more than 98.2 ± 4% for 0.6Au/Se-HAP. This work might boost more exploration of Au/Se-HAP as a promising material for biomedical utilizations.

The photooxidative desulfurization of thiophene (ThP) becomes a challenge in both industry and environmental remediation. Herein, we synthesize a visible-light-responsive Ag2WO4/Mn3O4 nanocomposite by a one-pot strategy. Depiction of the produced photocatalysts exposed the suppression of the surface structure and reduction of the bandgap energy by adding 15 wt% of Mn3O4 to Ag2WO4. The obtained nanocomposite shows a complete photooxidation of ThP within 1 h under visible light illumination at a dose of 1.2 g L−1. The significance of photocatalytic performance of Ag2WO4/Mn3O4 nanocomposite photocatalyst is referred to the enhancement of the visible light absorption and overthrow of the recombination of photogenerated charge carriers. The study opens the door for extensive use of nanocomposite photocatalysts as a novel functional material for the photooxidation of ThPs under visible light exposure.

The complexing capacities of thymoquinone with trivalent holmium(III) and gadolinium(III) metal ions and their overall stability constants in aqueous solutions were obtained using the HYPERQUAD 2008 program from the pH-potentiometric titration data. The molecular structures of thymoquinone—metal complexes formed in solutions were determined based on some spectral methods, and molecular modeling. The graphic representation of the complex species concentration curves is given by the distribution diagram performed by means of the HySS 2009 modeling program, which furnishes a variety of data presentations, including tables of concentrations of all species present in solution in the selected pH ranges.

A large fraction of population is suffering from waterborne diseases due to the contaminated drinking water. Both anthropogenic and natural sources are responsible for water contamination. Revolution in industrial and agriculture sectors along with a huge increase in human population has brought more amount of wastes like heavy metals, pesticides and antibiotics. These toxins are very harmful for human health, therefore, it is necessary to sense their presence in environment. Conventional strategies face various problems in detection and quantification of these pollutants such as expensive equipment and requirement of high maintenance with limited portability. Recently, nanostructured devices have been developed to detect environmental pollutants. Polymeric nanocomposites have been found robust, cost effective, highly efficient and accurate for sensing various environmental pollutants and this is due to their porous framework, multi-functionalities, redox properties, great conductivity, catalytic features, facile operation at room temperature and large surface area. Synergistic effects between polymeric matrix and nanomaterials are responsible for improved sensing features and environmental adaptability. This review focuses on the recent advancement in polymeric nanocomposites for sensing heavy metals, pesticides and antibiotics. The advantages, disadvantages, operating conditions and future perspectives of polymeric nanocomposites for sensing toxic pollutants have also been discussed.

Water is the founding fundamental of life and hence is a basic need of life. However, due to the ever-rising population, industrialization has emerged as a global issue. This problem has notably escalated in developing countries. Their citizens face problems such as floods, drought, and poor water quality. Due to poor water quality and sanitation problems, most health issues are caused by water-borne infections. In developing countries, untreated wastewater is released into water bodies or the ground, thereby polluting natural resources. This is due to the lack of sufficient infrastructure, planning, funding, and technologies to overcome these problems. Additionally, the urbanization of megacities in developing countries is highly accelerated, but it is disproportionate to the required resources for treating wastewater. Due to this biological oxygen demand (BOD): chemical oxygen demand (COD) ratio is increasing exponentially in developing countries compared to developed ones. Spreading awareness, education and supporting relevant research, and making stringent rules for industries can alone solve the water problem in developing countries.

Solanum nigrum is a traditional medicinal plant renowned as a cure for many diseases due to the presence of bioactive compounds. The Solanum nigrum complex refers to a group of more than 30 closely related but morphologically distinct taxa. Five indigenous taxa of this complex were investigated for their medicinal potential by using methanolic extracts. The efficacy of each plant was different for each of the seven bacteria studied. On comparing the MIC values, S. americanum was found to be most potent against Bacillus licheniformis (34 µg/mL), S. chenopodioides against Escherichia coli (78 µg/mL), S. nigrum against Bacillus licheniformis (49 µg/mL) and Escherichia coli (49 µg/mL), S. retroflexum against Escherichia coli (30 µg/mL), and S. villosum against Proteus mirabilis (45 µg/mL). The extracts were also subjected to six antioxidant assays. Moderate scavenging activity was observed by all plants in the DPPH free radical assay, but S. chenopodioides was the most effective. The total phenolic contents of the five plants were comparable, but the gallic acid equivalents of S. americanum and S. nigrum were the highest (26.58 mg/100 g GAE). The highest Trolox equivalent antioxidant capacity was observed for S. retroflexum, with the ABTS assay giving a TEAC value of 33.88 mM/100 g of dry weight. Metal-chelating activity against Fe2+ was observed to be highest for S. chenopodioides (70.37%). The FRAP value of S. nigrum was the highest (8.5 mM FeSO4·7H2O) among all taxa. The lipid peroxidation trend was very similar for all five samples. The results suggest the specified medicinal use of different members of the Solanum nigrum complex, which will also have significant nutritional value.

Co-substituted hydroxyapatite (HAP) with cationic rubidium (Rb+) and anionic selenite ( $${\text{SeO}}_{3}^{2 - }$$ ) was synthesized at different contributions of Rb+ ions. The chemical formula of the composition is [RbxCa(10–0.5x)(PO4)5(SeO3)(OH)2], where 0 ≤ x ≤ 0.8 with step 0.2. The structure and morphology of the as-prepared compositions were investigated upon the concentration of (Rb+) ions. It was mentioned that the roughness average (Ra) starts from 26.2 nm and grows up, reaching 42.6 nm. This noticeable roughness degree due to Rb insertions is reflected in adhesive ability in the biological environment. Rubidium dopant has a significant effect on particle size that inhibits size growth. The internal porosity could be classified as micropores except at x = 0.6 and 0.8, which are considered macro-pores. Rb/Se-HAP compositions' cell viability was investigated through the human osteoblast cell line (HFB4), and the life ratio achieved around 98.1 ± 3.9%. Furthermore, the additional Rb+ ions promote antibacterial activity, whereas the inhibition zone started from 1.6 ± 0.2 and 1.3 ± 0.3 mm and grew up to 5.3 ± 0.9 and 4.9 ± 0.8 mm for x = 0.0 and 0.8, against E. coli and S. aureus, respectively. Thus, the reported stoichiometric compositions are considered to be promising materials for biomedical applications.