Tungsten Oxide Nanoparticles Research Articles

Influence on the effect of Gd rare earth doped WO3 nanoparticles for enhanced photocatalytic and antibacterial activities: A nanoplate like morphology

Optimizing the photocatalytic antibacterial properties of nanomaterials by defect engineering is becoming a significant tool. The synthesis and characterization of Gd- doped tungsten oxide (Gd:WO3) nanoparticles for potential applications in wastewater treatment and antibacterial activity. Synthesis of the Gd:WO3 nanoparticles were prepared using the co-precipitation method, known for its simplicity and cost-effectiveness in producing nanomaterials. Samples were characterization by XRD confirmed the monoclinic crystal system of all samples and the incorporation of Gd ions into the WO3 lattice. SEM and TEM revealed a nanoplate-shaped morphology of the synthesized nanostructures. EDS confirmed the composition of Gd:WO3. FT-IR verified the presence of functional groups. XPS investigated the effect of Gd doping on the valence states of Gd:WO3, revealing the location of Gd ions within the WO3 lattice. UV-Vis showed increased absorption in the visible region and a decrease in the band gap with increasing Gd concentration up to 5 wt%, indicating potential photocatalytic properties. The nanoparticles demonstrated significant photocatalytic activity, achieving a 98 % degradation of methylene blue (MB) dye under visible light exposure. Among them, the Gd (5 wt%) nanoparticles exhibited the highest photocatalytic performance within 120 min. Additionally, these Gd (5 wt%) nanoparticles showed the greatest antibacterial effectiveness against Staphylococcus aureus, with an inhibition zone of 20 mm. Moreover, the study demonstrates the potential of Gd-doped tungsten oxide nanoparticles as efficient and environmentally friendly materials for wastewater treatment and antibacterial applications.

Enhanced electrocatalytic activity of hafnium doped tungsten oxide (Hf-WO3) for ultrasensitive detection of nonsteroidal anti-inflammatory drug

Efficient hafnium-doped tungsten oxide nanoparticles (Hf-WO3) were developed by hydrothermal approach and characterization was carried out by X-ray diffraction pattern (XRD), transmission electron microscopy (TEM), high resolution-transmission electron microscopy (HR-TEM), scanning transmission electron microscopy (STEM), X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS) techniques. Cyclic voltammetry (CV) and square wave voltammetry (SWV) techniques were employed to assess the electrochemical response of the fabricated carbon paste electrodes (CPE) for the analysis of mefenamic acid (MA). The objective of this work is to develop and optimize parameters to enhance the selectivity and sensitivity of Hf-WO3 modified sensor for the trace-level detection of MA, addressing its critical importance in both pharmaceutical and environmental analysis. The Hf-WO3 predominantly showed a monoclinic phase with some hexagonal peaks, confirming its good crystallinity and 1-D structure, which enhances charge transport and catalytic sites. XPS analysis confirmed the formation of pure Hf-WO3 by showing distinct W and Hf peaks and verifying their valences: W in the +6 state and Hf in the +4 state. CV showed that the Hf-WO3/CPE greatly enhances the electrochemical oxidation of MA compared to unmodified and tungsten oxide-modified electrodes, with a six-fold increase in peak current and notable redox activity attributed to improved surface properties and charge transfer efficiency. Under optimum experimental conditions, the Hf-WO3/CPE exhibits a low limit of detection (LOD) of 3.94 nM with dynamic concentration linearity ranging from 0.01 to 100.0 μM with good sensitivity of 1.74 μAμM−1cm−2. Furthermore, the Hf-WO3/CPE was employed in real-time analysis of MA in spiked urine samples and pharmaceutical tablet samples, which showed satisfactory recovery results ⁓ 98 %. Moreover, the electrode showed good stability over multiple measurements, and these results demonstrate that Hf-WO3/CPE is a promising sensor for MA detection.

Optimization of optical properties of nanocomposite films incorporating CWO and ITO nanoparticles for energy-saving window applications

Cesium tungsten oxide (CWO) and indium tin oxide (ITO) nanoparticles are potential candidates for application in energy-saving windows. However, most optical studies on these nanocomposite films lack systematic evaluation and design methods. In this work, the optical properties of spherical and cylindrical CWO and ITO nanoparticles under different geometric parameters based on the Lorenz–Mie and T-matrix theories are investigated, and spectral responses of CWO-PDMS and ITO-PDMS windows are calculated by solving the radiative transfer equation (RTE) using the Monte Carlo method. By evaluating and optimizing the geometric parameters of the nanocomposite films, energy-saving windows exhibit excellent optical performance, with a visible light transmittance that meets the indoor needs of the human eye (Tlum is about 0.6), and can shield most near-infrared light, especially CWO-PDMS windows (TNIR=0.04). Finally, a building energy consumption simulation analysis based on Energy Plus is conducted in three different cities: Jinan, Hong Kong, and Singapore. The results indicate that by adjusting the geometric parameters of nanoparticles, energy-saving windows can effectively reduce energy consumption in tropical and subtropical regions. This work provides guidance for the subsequent commercialization and experimental analysis of spectral selective composite films.

Enhancing the electrochemical performance of LiNi0.8Co0.1Mn0.1O2 by surface modification with homemade high-purity hexagonal phase tungsten oxide nanoparticles

Nickel-rich layered oxides with high energy density and acceptable cost are considered as one of the most ideal cathode materials for power batteries. However, its large-scale production and application still face the challenge in terms of rapid capacity fading and poor structural stability, which has prompted research into surface coating materials/technologies within both academic and industrial fields. In this work, A feasible and environmental friendly fabrication method of high-purity hexagonal phase tungsten oxide (h-WO3) nanoparticles as surface modification of LiNi0.8Co0.1Mn0.1O2(NCM) is proposed.The results indicate that NCM modified with h-WO3 has lower Li+/Ni2+ mixing rate, superior rate performance, and better cycling stability than the pristine NCM. Although tungsten oxide is widely used as surface modification due to its excellent physical and chemical properties, but its crystal type has not been considered, and there is little research on the theoretical explanation of h-WO3 modification.This work reveals the working mechanism of h-WO3 from the perspective of interface and crystal type, which can provide meaningful reference for obtaining nickel-rich layered oxides with excellent electrochemical properties.

Developing green slag/bentonite-based geopolymers modified with meso-porous tungsten oxide: Zeolitic phases, mechanical performance and gamma-radiation mitigation

In an attempt to maintain the sustainable development goals in the construction sector via reducing the raw-materials/energy consumption and greenhouse-gas emissions related to cement production, a green nano-modified slag/bentonite-based alkali-activated material was developed. Firstly, the green composites were prepared by mixing slag and bentonite with a ratio of 2:1. Several factors like NaOH-concentration (6, 8, 10 wt%); thermal treatment of bentonite (as-received “RB” and thermally treated at 650 °C “TB”); curing conditions (normal-curing for 3 and 28-days as well as hydrothermal-curing at 3, 6, 9, 15 bar for 4 h) and meso-porous tungsten oxide nano-particles “WO3-NPs” inclusion (0.25, 0.5 and 1 wt%) were studied to assign the optimum conditions for fabricating composites with adequate mechanical properties and radiation-shielding ability. The mechanical performance and radiation shielding were evaluated by measuring the compressive-strengths and linear attenuation coefficient “μ”/ half value layer “HVL” using 137Cs, respectively. The results reveal the feasibility of using 8 wt% NaOH, TB, hydrothermal-curing at 3 bar/4 h and 0.5 wt% WO3-NPs in fabricating low-cost/pre-cast/environmentally friendly building material with superior compressive-strength (53.6 MPa). Also, the radiation shielding results substantiate that this developed composite achieved adequate μ and HVL values, referring to its efficiency as a radiation-blocker. The synergistic impact of alkali-hydrothermal-activation, the high pozzolanicity of TB and the nucleation-site/potential-seeds effect of WO3-NPs are the main reasons behind forming strength-giving-phases from stratlingite, hydrogarnet, analcime and pentasil zeolitic phase (ZSM-5), as proved by X-ray diffraction (XRD), thermogravimetric analysis (TGA/DTG) and scanning electron microscopy (SEM). The presence of such phases reinforced the microstructure, thus improving the mechanical performance and radiation shielding capability.

Photodecoration of tungsten oxide nanoparticles onto eggshell as an ultra-fast adsorbent for removal of MB dye pollutant

Nowadays, the use of natural wastes and adsorbents along with their modification by simple and new methods based on metal oxides to remove dye pollutants has been the focus of many researchers. In this study, for the first time, simple and low-cost modification of eggshell (EGS) with tungsten oxide (WO3) based on the photochemical modification method as a green, ultra-fast, cost-effective, and biodegradable adsorbent is reported to remove of methylene blue (MB) dye pollutant. The EGS modified by WO3 was investigated by EDX, EDX mapping, XRD, FE-SEM, and UV–Vis Diffuse Reflectance (DRS) analyses. The obtained results show that the modified EGS by WO3 has more than ten times (78.5%) the ability to remove MB dye pollutant within 3 min compared to bare EGS (11%). Various parameters including dye pollutant pH, dye concentration, adsorbent dosage, and reusability of the WO3/EGS adsorbent for removal of MB dye pollutant were investigated and the result show that the adsorbent capacity of WO3/EGS is 1.64 mg g−1. EGS adsorbent The synthesis of WO3/EGS adsorbent with a novel photochemical method as a fast and very cheap adsorbent with excellent efficiency can be a promising alternative adsorbent for various purposes in removing dye pollutants from water environments.

Nanoparticles of Cs0.33WO3 as Antibiofilm Agents and Photothermal Treatment to Inhibit Biofilm Formation.

Metal oxide nanoparticles with photothermal properties have attracted considerable research attention for their use in biomedical applications. Cesium tungsten oxide (Cs0.33WO3) nanoparticles (NPs) exhibit strong absorption in the NIR region due to localized surface plasmon resonance, through which they convert light to heat; hence, they can be applied to photothermal treatment for bacteria and biofilm ablation. Herein, Cs0.33WO3 NPs were synthesized through solid-phase synthesis, and their physical properties were characterized through Zetasizer, energy dispersive X-ray spectroscopy, Fourier transform infrared spectrometer, and scanning and transmission electron microscopy (SEM and TEM, respectively). Burkholderia cenocepacia isolates were cultured in tryptic soy broth supplemented with glucose, and the biofilm inhibition and antibiofilm effects of the NPs were determined using a crystal violet assay and the Cell Counting Kit-8 (CCK-8) assay. The biofilm morphology and viability of NP-treated cultures after NIR irradiation were evaluated through SEM and confocal microscopy, respectively. The cytotoxicity of NPs to human macrophages was also assessed using the CCK-8 assay. The NPs effectively inhibited biofilm formation, with a formation rate of <10% and a viability rate of <50% at the concentration of ≥200 μg/mL. The confocal analysis revealed that NIR irradiation markedly enhanced biofilm cytotoxicity after treatment with the NPs. The assay of cytotoxicity to human macrophages demonstrated the biocompatibility of the NPs and NIR irradiation. In sum, the Cs0.33WO3 NPs displayed effective biofilm inhibition and antibiofilm activity at 200 μg/mL treatment concentration; they exhibited an enhancement effect under the NIR irradiation, suggesting Cs0.33WO3 NPs are a potential candidate agent for NIR-irradiated photothermal treatment in bacterial biofilm inhibition and antibiofilm.

Sub-ppm of toxic gases detection on Ag-doped WO3 nanosensor

AbstractRecent investigations reveal an increasing interest in detecting toxic substances that, if present in the environment at low concentrations, can cause serious health conditions. Moreover, some of these toxic substances can be found as gases in human breath due to disease. Nanomaterial-based sensors have emerged as a crucial area of research for this purpose. This study focuses on silver-doped tungsten oxide nanoparticles (Ag/WO3) as nanosensors capable of detecting trace amounts of toxic gases at room temperature. These gases include Hydrogen sulfide (H2S), as well as other toxic gases like acetone, Ammonia (NH3), Ethanol (C2H5OH), and Acetone ((CH3)2CO). The gas-sensing behavior of Ag/WO3 nanosensors was investigated at extremely low concentrations of these gases. X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface, X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) were employed to analyze the material's structure and chemical state. The sensor exhibited sensitivity to gas concentrations as low as 0.25 ppm, with a robust response of up to 80%. Notably, it showed the highest selectivity toward H2S gas compared to ethanol, ammonia, and acetone. The sensor's performance was also evaluated under varying temperatures and humid conditions, demonstrating reliable responses at room temperature. Heron, the synthesis of Ag/WO3 sensors with excellent sensitivity at extremely low gas concentrations is reported, making this sensor a promising tool for detecting toxic gases that threaten human health. Furthermore, the potential implications of this research on human health are significant, as detecting low concentrations of these gases can be a potential tool for the diagnostic process as well as health and environmental monitoring.

Tungsten oxide nanoparticles encapsulated by porous carbon for boosting H2S selective oxidation performance

Effective advancements for H2S removal are desperately expected to meet security and ecological necessities as natural guidelines on H2S emissions. Selective catalytic oxidation, as a green technology, has attracted attention owing to its direct conversion of H2S to S without thermodynamic constraints. Herein, we report a carbon-encapsulated WO3 (C@WO3–300) catalyst with nearly 100 % H2S conversion and 99 % S selectivity. Importantly, it likewise accomplishes noteworthy catalytic stability (over 120 h of continuous operation) and water resistance. Excellent durability may be attributed to the ideal porosity of C@WO3, which facilitates the adsorption and activation of H2S and O2. Additionally, the abundant lone pair electrons of carbon support can optimize the chemical environment of WO3-based catalysts and thereby benefit the O2 activation. This study provides a new avenue for the rational design of efficient and durable catalysts for continuous catalytic oxidative desulfurization.

Label-free colorimetric analysis strategies based on adsorption-responsive surface-enhanced photochromic phenomena of tungsten(VI) oxide nanoparticles for amino acids.

Herein, we present a colorimetric detection method based on the surface-enhanced photochromic phenomenon of tungsten (VI) oxide (WO3) nanocolloid particles for α-amino acid (AA) molecules, including L-aspartic acid (Asp), L-glutamic acid (Glu), L-histidine (His), L-isoleucine (Ile), L-leucine (Leu), L-lysine (Lys), L-phenylalanine (Phe), and L-valine (Val). The UV-induced photochromic phenomena in the AA/WO3 binary aqueous systems were investigated using UV-Vis absorption spectrometry. The adsorption properties of the AA molecules on the surface of the WO3 nanocolloid particles have been identified using a combination of adsorption isotherm analysis and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. A good linear correlation between the concentration of the AAs adsorbed on the surface of the WO3 nanocolloid particles and the initial photochromic coloration rate in the corresponding UV-irradiated WO3 colloidal aqueous solution was obtained with over three orders of magnitude, indicating that the surface-enhanced photochromic phenomenon of the WO3 nanocolloid particle can be used to detect the AA molecules. In addition, based on the results of the UV-Vis absorption, ATR-FTIR, and adsorption isotherm analyses, we have experimentally demonstrated that the AA/WO3 binary aqueous system with inner-sphere adsorbed Ile, Leu, Lys, or Val molecules on the surface of the WO3 nanocolloid particles exhibits a more significant surface-enhanced photochromic phenomenon than the system with outer-sphere adsorbed Asp, Glu, His, or Phe molecules. The strong inner-sphere adsorption of the AA molecules successfully improved the limit of detection. This study provides valuable insights into a "label-free" colorimetric assay system based on the surface-enhanced photochromic phenomenon of the WO3 nanocolloid probe.

Oxygen-deficient WO3 for stable visible-light photocatalytic degradation of acetaldehyde within a wide humidity range

Indoor VOCs pollution has attracted broad attention for its harm to mankind’s health recent years. Photocatalytic degradation of indoor VOCs holds great prospects in addressing these health concerns in daily life. However, traditional photocatalysts have a large recombination rate of charge carriers and a decrease of the photocatalytic degradation efficiency under high relative humidity. Herein, uniform tungsten oxide nanoparticles with enriched oxygen vacancies (WO3-U) were synthesized by a direct annealing method with urea addition, which exhibited superior performance in the visible-light photocatalysis. The reaction rate constant value of photocatalytic acetaldehyde degradation over WO3-U catalyst was above 3 times higher than that of pristine WO3 sample. More importantly, the WO3-U catalyst maintained stable and excellent photocatalytic performance at relative humidity range of 25–100 %. Except for the enhanced photogenerated charges separation, abundant oxygen vacancies could effectively accelerate O2 activation to generate •O2−, which accounted mainly for the initial conversion of acetaldehyde. Then the subsequent transformation of •O2− into •OH to promoted the final mineralization of acetaldehyde. In addition, the presence of oxygen vacancies also facilitated H2O dissociation to form surface hydroxyl groups, which increased the adsorption of acetaldehyde, resulting in the consistent photocatalytic performance of WO3-U catalyst within a wide humidity range. This work provides guidelines to design visible-light responsive photocatalysts with efficient activity at high humidity conditions for indoor VOCs degradation.

Transition metal oxide catalytic abilities for fuel cell applications: Density functional theory (DFT) studies

Because of its heavy reliance on fossil fuels, the world's existing energy supply releases pollutants into the atmosphere. Researchers have conducted extensive studies on greener energy sources, particularly fuel cell technology, which generates power from electrochemical energy while emitting minimal carbon. But there are obstacles to fuel cell efficiency and commercialization, such as the slow oxygen reduction reaction (ORR) and the expensive and unstable platinum (Pt) catalysts used in fuel cell membranes. This work explores the use of tungsten oxide, cobalt, and titanium oxide nanoparticles as inexpensive, active electrocatalysts. Despite extensive research on the monoxides of these metals, their bimetallic compositions when combined with oxygen to function as fuel cell catalysts remain poorly understood. This work evaluates the catalytic capabilities of the crystallographic surfaces of these oxides using Density Functional Theory (DFT) via CASTEP and DMol3, as well as the Adsorption Locator module. These surfaces, which include CoWO4, Co3WO8, and TiWO4, have different levels of stability and reactivity when it comes to absorbing hydrogen and oxygen. This makes them potentially useful for changing the hydrogen oxidation and oxygen reduction reactions in fuel cells.

Photocatalytic degradation of textile dye with titanium (IV) doped tungsten oxide nanoparticles

Water pollution from textile industries is a major concern with respect to the availability of clean drinking water. The removal of textile (organic) dyes through photocatalytic degradation with pure WO3 and titanium (IV) doped tungsten oxide [Ti (IV)-WO3] nanospheres were studied under visible light. The WO3 and Ti (IV)-WO3 nanospheres were synthesized via microwave-assisted method at microwave power of 160 W for the duration of 20 mins. The as synthesised WO3 and Ti (IV)-WO3 nanospheres were characterized for their structural, microstructural, and spectroscopic properties by using powder X-ray diffraction (XRD), UV–Visible (UV-Vis) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and High-resolution transmission electron microscopy (HR-TEM). The X-ray diffractograms confirmed the formation of highly pure WO3 and Ti (IV)-WO3 nanospheres. The average crystallite size of WO3 and Ti (IV)-WO3 nanospheres were calculated as 53.37 nm and 35.24 nm respectively using Debye Scherrer equation. The bandgap of Ti (IV)-WO3 was found to be decreased to 2.5 eV from 3.2 eV (WO3) respectively. It can be deduced that Ti (IV)-WO3 can be utilized as efficient visible light (λ&gt;420 nm) driven photocatalyst as the bandgap was &lt; 3 eV. The agglomerated spherical nanoparticles were seen for WO3 and Ti (IV)-WO3 in the HR-TEM images. The photocatalytic activity of textile dye was analyzed by UV-Vis spectrophotometer under visible light. The photocatalytic organic dye degradation was investigated. The enhanced photocatalytic activity of titanium (IV) doped tungsten oxide (10 wt%) was observed to be ~100% in 100 mins. This makes titanium (IV) doped tungsten oxide nanospheres, a potential nanomaterial for water purification.

Photochemical modification of tea waste by tungsten oxide nanoparticle as a novel, low-cost and green photocatalyst for degradation of dye pollutant

So far, many adsorbents and nanocomposites have been synthesized by different methods and used to remove or degradation of dye pollutants. Nowadays, the use of natural adsorbents and their modification with simple methods based on metal oxides are of interest to many researchers. In this study, for the first time, we report the simple and low-cost modification of tea pomace waste (TPW) with tungsten oxide (WO3) based on the photochemical method as a green, cost-effective, and biodegradable photocatalyst for the degradation of Rh B dye pollutant. The results obtained from FE-SEM, EDAX, XRD, XPS, PL, BET and UV–Vis Diffusive Reflectance (DRS) analyses confirmed the successful modification of the TPW surface with WO3 (WO3/TPW). The parameters affecting the photocatalytic behavior of WO3/TPW, including the time of photochemical modification and the type of radiation on its photocatalytic activity, were carefully optimized. WO3/TPW showed excellent photocatalytic activity compared to TPW for the degradation of Rh B dye pollutant under UV light for 30 min (94 %). Finally, the effective parameters on the value of Rh B dye degradation by WO3/TPW photocatalyst including pH, adsorbent dosage, the concentration of dye pollutant, and the kinetics of the degradation process were studied. It is expected that this type of photochemical modification method and natural WO3/TPW photocatalyst will be a promising path for the synthesis, modification, and increase of the photocatalytic performance of natural adsorbents.

Synergistic effect of Ag2WO4 interconnected nanoclusters for enhanced photovoltaic performance

Tungsten oxide nanoparticles (PW NPs) and silver-doped tungsten oxide nanocomposites (SW NCs) were synthesized via hydrothermal method. Structural, optical, morphological, and electrical properties of the synthesized samples were characterized by X-ray powder diffraction (XRD), Scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDAX), and UV–visible spectroscopy. XRD results confirmed the formation of Ag2WO4 NCs with an average crystallite size ranging from 38 to 9 nm. SEM analysis revealed the formation of nanoclusters. Further SW4NCs shows highest rate constant (0.108 min−1) for methyl blue (MB) dye degradation. Variation in the electrical conductivity and activation energy was studied by DC conductivity studies. Dye-sensitized solar cells (DSSCs) were fabricated using PW and SW NCs films as photoanodes simultaneously, and the photoconversion efficiency (PCE) was found to increase.

Hydrogenation Synthesis of Sub-stoichiometric Tungsten Oxide (WOX) Nanoparticles and Its Superior Decompose Rhodamine B Behavior

Hydrogenation Synthesis of Sub-stoichiometric Tungsten Oxide (WOX) Nanoparticles and Its Superior Decompose Rhodamine B Behavior

Structural, morphological, thermal, mechanical, positron annihilation, and γ-ray shielding studies of nano-tungsten oxide/polyvinyl alcohol composites

Tungsten oxide nanoparticles were synthesized. Metal/polymer composites of nano-sized WO3 and poly vinyl alcohol were blended by the casting method with concentrations of WO3. The structural, morphological, thermal, and mechanical characteristics of the prepared samples were investigated. The γ-ray attenuation properties of the synthesized composites were examined using γ-ray spectrometers, and the γ-ray mass absorption coefficients were measured using 662 keV γ-ray of 137Cs radioactive source. The defects and microstructure changes of the composites were probed using positron annihilation lifetime and Doppler broadening techniques. The shielding performance and thermal stability improved with increasing the concentration of WO3, and some of the mechanical properties, in particular the elongation at break, deteriorate. The contribution of WO3 has a strong effect on reducing the relative fractional free volume, which in turn helps to increase the γ-ray absorption of the composites. The use of a 50–70 % WO3/PVA composite is recommended.

Preparation and characterization of tungsten oxide fortified poly(urea-formaldehyde) microcapsules for self-healing coatings

Radiation-resistant poly(urea-formaldehyde) (PUF) microcapsules with a bisphenol A diglycidyl ether/butyl glycidyl ether core were prepared via emulsion polymerization. Tungsten oxide (WO3) nanoparticles were incorporated into the polymer shell to improve radiation resistance of the resultant PUF microcapsules. Microcapsules prepared with modified WO3 nanoparticles had an average diameter of 117 μm, an encapsulation efficiency of 48%, and evenly dispersed nanoparticle incorporation of 3.5 wt%. Modification of dense WO3 nanoparticles was necessary for even dispersion into PUF microcapsule shells. The corrosion protection properties of epoxy films cast on mild steel were demonstrated via scratching and exposure to salt solution. Films containing modified WO3 fortified microcapsules demonstrated self-healing and retained corrosion protection properties. Under gamma irradiation, WO3/PUF microcapsules exhibited less degradation of epoxy healing core compared to microcapsules that were not fortified with WO3.

Towards a green climate: Production of slag–red brick waste-based geopolymer mingled with WO3 nanoparticles with bio-mechanical achievements

According to the sustainability concept, this work developed a green geopolymeric composite (Geo) prepared by mingling 50 wt%slag+ 50 wt%brick-waste (BW) as an alternative eco-friendly and low-cost cementitious material. The main target of this study is to fnd a solution to the problem of poor characteristics of binding materials containing high proportions of BW; most previous studies recommended using only 10–20 wt%BW. The compressive-strength results showed that replacing slag with 50 wt% BW reduced the strength from 47 to 24.6 MPa at normal curing conditions for 28-days, referring to the detrimental impact of BW on mechanical performance. In an endeavour to enhance the mechanical performance of this composite, different doses from laboratory-prepared tungsten oxide nanoparticles (0.25, 0.5, 1 wt%WO3-NPs) and hydrothermal curing at various steam-pressure/periods were used. From an economic point of view, hydrothermally treated Geo-paste modified with 0.25 wt%WO3-NPs at 3 bar/4hrs was selected as an ideal composition/curing-conditions; the compressive-strength reached 54.5 MPa exceeding the standard limit of Portland cement (42.5 MPa). This clearly shows the synergistic role of using WO3-NPs and hydrothermal curing to enhance the compressive-strength, which was confirmed using different analysis techniques. XRD, TGA/DTG and SEM/mapping proved that the catalytic performance of WO3-NPs/hydrothermal-curing participates in augmenting binding hydrates, creating a cubic-stable-phase of tricalcium-aluminate-hydrate (C3AH6) and different types of zeolitic-like structure (spherical Zeolite-NaP, rods analcime and stacked-plates cancrinite). To maximize the benefits of employing WO3-NPs in the developed composites, their anti-microbial activity was studied. The measured inhibition zone around specimens containing WO3-NPs proved that these composites have a superior self-cleaning efficiency against Candida albicans, Mucor circinelloides, Salmonella typhi and Staphylococcus aureus due to the WO3-NPs’ photocatalytic activity.

Amino-functionalization of tungsten oxide nanoparticles for stable decoration in the active layer of alumina-supported inorganic-organic hybrid membrane with super-wettable and photocatalytic self-cleaning surfaces for crude oil-in-water emulsion separation

The ceramic membrane was hybridized with an amino-functionalized inorganic metal oxide and organic polymer to achieve the optimal oil and water surface wettability and photo-catalytic self-cleaning capability. The resulting membrane was used for the treatment of crude oil-contaminated wastewater under cross-flow filtration mode. The fundamental functional material, tungsten oxide nanoparticles (NH2-WO3 NPs) modified by aminopropyl triethoxysilane (APTES) was created and coated on the alumina ceramic support surface via interfacial polymerization, in which the material covalently cross-links on the membrane's active layer in the presence of terephthaloyl chloride (TPC) as a cross-linker and piperazine (PIP) as an external amine. Achieving a unique combination of oil and water surface wettability- superhydrophilicity (0° water-in-air contact angle) and underwater super-oleophobicity (160.25° under-water oil contact angle) was the key to creating the water-permeating NH2-WO3/PA@alumina ceramic membrane. The second advantageous feature of the membrane is its capacity for self-cleaning, which results from WO3 NP's innate photocatalytic activity that has been further enhanced by amino functionalization. A water permeate flux of up to 250 L m−2 h−1 and an oil/water separation efficiency of nearly 100 % were attained for an oil concentration of 50 ppm of crude oil-in-water emulsion when NH2-WO3/PA@alumina ceramic membrane was employed as a separation medium in a cross-flow filtration system for the separation of crude oil-in-water emulsion. Furthermore, the permeate flux decreased to ∼25 % of its initial flux after using NH2-WO3/PA@alumina ceramic for approximately 210 min. This was caused by organic pollutants in the oily water clogging the membrane pores. The permeate flux was recovered by exposing the membrane to UV light for photo-catalytic self-cleaning. Due to its water-passing nature, this membrane has high efficiency. Additionally, because the self-cleaning add-on removes the need for chemical cleaning, it is environmentally friendly.