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Regarding the presence of residual active drug compounds in the municipal effluents and the effluents of pharmaceutical factories, the removal of these compounds increases the resistance of microorganisms, and environmental hazards, such as genetic disorders in the aquatic reproduction and possible damage to human health is necessary. In recent years, using the Mixed-Matrix-Membranes (MMMs) for their high removal efficiency was considered. In the present study, polyether sulfone (PES) membranes, and composite membranes with MIL10-OH/Chitosan (CS), were synthesized and characterized. SEM analysis shows that with the addition of MOF modified with CS, the number and size of micropores and porosity increase compared to the PES membrane. By adding 0.05 wt % of MIL101-OH and MIL101-OH/CS to the PES membrane, the pure water flux increased from 5.1 kg/m2 h to 9.2 and 9.9 kg/m2 h. Increased porosity in the membranes led to a decrease in the resistance of flowing water, and ultimately increased the membrane's permeability. Increased membrane hydrophilicity, as well as membrane surface roughness, reduced membrane clogging. By adding MOF with CS to the PES membrane, the flux recovery ratio increased from 45 % to 95 % in terms of the increase of hydrophilic functional groups of membrane. Furthermore, reversible fouling increases and irreversible fouling in MMMs significantly decreased. Diclofenac sodium (DCF) was separated better than cefixime (CFX). Thus, the removal percentage for DCF was 95 % and for CFX drug is 90 %. By comparing the removal percentage, it can be seen that the performance of MMMs with MIL101-OH/CS was better than MMMs with MIL101-OH, and adding CS to MOF and PES membrane improved membrane performance to remove DCF and CFX. [ABSTRACT FROM AUTHOR]

Air pollution is known as one of the most important causes of death in the whole world. Therefore, pollution reduction to achieve clean air was noticed by everyone. This way, using nanotechnology to control air and monitor is a novel approach. This paper investigates the effect of the number of graphene nano-pores on the SiO 2 separation from the H 2 O vapour in the presence of an external electric field with the magnitude of 0.01 V/Å using the molecular dynamics (MD) method. The electric field affects the charged particles and causes disturbance in the structure. It also prevents SiO 2 nanoparticles from passing through the graphene nanosheet. Also, the presence of carbon nanosheets acts as a membrane and affects the diffusion of water in the nanostructure. So, the results show that in the presence of a nano-pore, the number of H 2 O molecules reaches to 496 and 568 in reservoirs 2 and 3. Also, the number of SiO 2 nanoparticles reaches 10 and 4 in reservoirs 2 and 3. This shows that in reservoirs 2 and 3, about 80% and 60% of the SiO 2 nanoparticles are separated. As mentioned before, the electric field prevents the passage of SiO 2 nanoparticles through the graphene nanosheet. As the number of graphene nano-pores increases by 2, 3, 4, and 5, the number of passing water molecules increases. Considering that the number of graphene nano-pores has increased and the movement path of particles has increased, the number of passing particles almost increases. However, the electric field prevents the passage of SiO 2 nanoparticles. According to the results, the suggested setup can be employed for designing highly efficient nanostructured membranes for air purification and monitoring. [Display omitted] [ABSTRACT FROM AUTHOR]

Developing interfacial connections is one of the breakthrough strategies to improve the photocatalytic activity. Herein, ZnBi 2 O 4 nanoparticles-ZnO nanorods heterojunction was successfully synthesized and used, as a dual-function photocatalyst, for photocatalytic degradation of Bisphenol A and hydrogen production with improved photocatalytic activity under simulated sunlight irradiation. The highest H 2 production (3.44 mmol g−1 h−1) was obtained for ZnO-20 wt% ZnBi 2 O 4 sample, which is around 12.7 times higher than pure ZnO. According to the HRTEM result, the intimate interfacial connections are formed between ZnO and ZnBi 2 O 4 which could act as trapping centers for charge carriers and results in the boosted photocatalytic activity. Further, a high aspect ratio of 1D ZnO nanorods and small size of 0D ZnBi 2 O 4 nanoparticles (~10 nm) increases the number of interfacial contacts and thus the charge carriers' recombination was suppressed more efficiently. Based on the trapping experiments, ESR and Mott-Schottky analysis, ZnBi 2 O 4 –ZnO hybrid photocatalyst followed the S -scheme charge transfer mechanism. • Novel 0D/1D ZnBi 2 O 4 /ZnO p-n heterojunction was successfully prepared. • The prepared hybrid system revealed improved H 2 production and BPA decomposition. • The highest hydrogen evolution (3.44 mmol.g−1.h−1) was achieved on ZnO–20%ZnBi 2 O 4. • S -scheme mechanism was suggested for boosted photocatalytic activity. • The defects formed at the interfacial contacts decreased the recombination rate. [ABSTRACT FROM AUTHOR]

In this study, the MGO@SnO as a new nanocatalyst with diverse chemical/physical properties was generated by the combination of graphene oxide covered with magnetic iron oxide (MGO) and tin oxide (SnO(x)) nanoparticles used for biodiesel production from soybean oil. Before GC-FID analysis, the nanostructured MGO@SnO was successfully employed to transesterify soybean oil to FAMEs (biodiesel). The proposed material was characterized using Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometer (EDX), X-ray diffraction (XRD), and vibrating sample magnetometer (VSM). Given the acidic-alkaline nature of the proposed catalyst, it has a strong probability of creating carbocation ions to attack with methanol and subsequently converting the triglycerides to methyl ester (FAMEs). In further experiments, it was found that the ideal reaction parameters were a ratio of MGO to SnO of 1:0.5, a molar ratio of soybean oil to methanol (MeOH) of 1:10, a reaction period of 180 min, and a reaction temperature of 120 °C. Furthermore, the MGO@SnO catalyst demonstrated adequate catalytic performance (>88 %) for transforming the triglycerides of soybean oil to FAMEs (biodiesel) as compared to pure SnO NPs (74 %) and plain MGO (69 %) at similar conditions. [ABSTRACT FROM AUTHOR]

• Novel binary functional catalyst developed based on amine and metal oxide. • Polyaniline supported Cobalt oxide catalyst used for biodiesel production. • The catalyst converted triglyceride via proposed acid base mechanism. • The catalyst provided appropriate FAMEs yield >90 %. The development of novel heterogeneous catalyst materials with unique chemical/physical properties has attracted great attention in biodiesel production. Herein, the binary functional organic–inorganic nanocomposite based on polyaniline decorated with magnetic iron oxide and cobalt oxide nanoparticles were used to synthesis MPANI@Co 3 O 4 as novel nanocatalyst. The proposed material was fabricated through a facile hydrothermal technique coupled with a one-pot polymerization method. The morphology and structure of as-prepared MPANI@Co 3 O 4 materials were evaluated using field-emission scanning electron microscope (FESEM), Fourier transform infrared spectroscopy (FTIR), vibrating-sample magnetometer (VSM), and energy dispersive X-Ray spectrometer (EDX). The FESEM-EDX provided the metal oxide nanoparticles well incorporated onto polyaniline with C (28.32 %), N (48.45 %), O (21.44 %), Fe (1.69 %), and Co (1.10 %). The MPANI@Co 3 O 4 was successfully used as a high-performance nanocatalyst in transesterification of waste cooking oil (WCO) to FAMEs (biodiesel). Due to the acidic-alkaline nature of the proposed catalyst, it has high potential to produce methoxy ions followed by attacking the carbonyl groups of triglycerides. In further experiments, the satisfactory reaction conditions obtained were MPANI to Co 3 O 4 ratio of 1:1, WCO to methanol molar ratio of 1:10, 240 min reaction time and at 90 °C reaction temperature. Moreover, under optimum conditions, the catalyst offered desirable catalytic performance (>93%) to catalyze the triglycerides of WCO to biodiesel (FAMEs). Therefore, the novel binary organic–inorganic nanocomposite can be used as co-catalyst material in biodiesel processing. [ABSTRACT FROM AUTHOR]

The sustainable process and direct synthesis of 5-hydroxymethylfurfural (5-HMF), a valuable renewable biofuel and biochemical, was systematically studied using inexpensive catalysts and recyclable magnetic nanocatalysts. Fe 3 O 4 @SBA-16-SO 3 H was obtained by the synthesis of SBA-16 and was modified by MPTES and H 2 O 2. After that, Fe 3 O 4 was synthesized via chemical precipitation and mixed with SBA-16-SO 3 H for easy separation and recovery (using five cycles of catalysts with excellent yield for the synthesis of 5-HMF) and a new magnetic heterogeneous catalyst for the synthesis of 5-HMF that was found to have 95% glucose and fructose conversion and 97% yield of 5-HMF, respectively. The prepared catalyst was characterized by FT-IR, EDAX, XRD, FE-SEM, TEM, VSM, BET, and TGA techniques. The experiments were carried out with good yields and implied that the catalytic method was effective, convenient, and promising for the synthesis of 5-HMF. The present study opens a new avenue for the renewable one-pot synthesis of 5-HMF, a precious product. The efficient conversion of biomass into value-added compounds under mild and safer conditions is a cornerstone of our current research efforts to meet the needs of the chemical industry with sustainable development. [Display omitted] [ABSTRACT FROM AUTHOR]

Ti-XAl-2Fe-3Cu (X = 2.7, 4 wt%) alloys with a high tensile yield strength of up to 1150 MPa were synthesized using powder compact extrusion from blended TiH 2 and elemental powders. The microstructures and mechanical properties of the extruded rods without and with a homogenization heat treatment at 1000 °C for 1 h followed by furnace cooling were investigated. It was found that the Al content and heat treatment had significant effects on the microstructures and mechanical properties. With increasing the Al content from 2.7 to 4 wt%, the average lamellar colony size and lamellar thickness of the as-extruded Ti-XAl-2Fe-3Cu alloy decreased from 442.4 to 224.1 µm and 6.7–5.2 µm respectively. The heat treatment increased the lamellar thickness as well as the level of partitioning of Fe and Cu between α and β phases. As a result of the microstructural changes, increasing Al from 2.7 to 4 wt% caused a slight increase in the strength of Ti-XAl-2Fe-3Cu alloys without changing the ductility, while the heat treatment slightly reduced the strength of the alloys, but clearly increased their tensile ductility. The correlation between microstructures and mechanical properties is discussed. [ABSTRACT FROM AUTHOR]

• Novel Bi 2 WO 6 -ZnBi 2 O 4 heterojunction was prepared by sonochemical assisted hydrothermal method. • Sonochemical pretreatment caused spherical to flake-like morphology evolution. • The optimal Bi 2 WO 6 -20ZnBi 2 O 4 revealed good stability (4% loss) after 5 cycling runs. • Direct Z-scheme mechanism was proposed for the enhanced photodegradation of MG. • Bi 2 WO 6 -ZnBi 2 O 4 can efficiently remove both MG dye and colorless 2,4-DCP contaminants. In this work, novel Bi 2 WO 6 -ZnBi 2 O 4 p-n heterojunction was successfully synthesized through combination of sonochemical and hydrothermal procedures. The results revealed that the sonochemically prepared nanocomposites had spherical shape with amorphous structure which became crystalline particles with flak-like morphology after hydrothermal treatment. Bi 2 WO 6 -ZnBi 2 O 4 nanocomposite with 20 wt% ZnBi 2 O 4 content demonstrated the highest photocatalytic performance compared to the pure Bi 2 WO 6 and ZnBi 2 O 4 samples toward the degradation of Malachite Green (MG). This finding is associated with the efficient separation of photo-generated electron/hole pairs due to the formation of interfacial charge transfer between Bi 2 WO 6 and ZnBi 2 O 4. However, further ZnBi 2 O 4 loading had no significant effect on the enhancement of photocatalytic activity of nanocomposite samples owing to the shielding effect of ZnBi 2 O 4 against incident light. The obtained results were further verified by optical and photocurrent density measurements. Based on the obtained results from active species trapping experiments, electron spin resonance and Mott-Schottky calculations, the Z-scheme charge transfer pathway was proposed as the predominant mechanism for the photocatalytic reactions. Also, the photocatalytic degradation of 2,4-dichlorophenol, as a colorless model pollutant, was conducted on optimal composite sample to study the possible contribution of MG dye sensitization mechanism in the enhancement of photocatalytic efficiency. [ABSTRACT FROM AUTHOR]

• Glycerol-assisted self-template approach was utilized to prepare pyrite-phase of high-entropy transition-metal sulfides (CoFeNiMnCu)S 2 nanoparticles. • The (CoFeNiMnCu)S 2 nanoparticles exhibited a low overpotential of 284 mV with a low Tafel slope of 57 mV/dec in a 1.0 M KOH solution. • The superb electrochemical activity of quinary (CoFeNiMnCu)S 2 was preserved over 8 h OER reaction and long-term potential-cycling after 1000 CV cycles. • The electrocatalytic behavior of various samples toward OER pertinent to their specific electronic features and multi-metallic interaction were comprehensively discussed. Developing extremely efficient electrocatalysts for oxygen evolution reactions (OER) is a decisive step toward the progression of rechargeable metal-oxygen batteries, CO 2 reduction, and water-splitting. Nanoporous high-entropy transition-metal sulfides (np-HETMS) represent a new generation of promising OER catalysts by virtue of their exceptional catalytic activity. However, their synthesis maintains to be a challenge by reason of the thermodynamic immiscibility of the constituting multi-principal metallic elements in the sulfide structure. Herein, for the first time, the np-HETMS ((CoFeNiMnCu)S 2) nanoparticles with pyrite-phase was synthesized via a facile and easy adaptable glycerol-assisted self-template approach to resolve the immiscibility of multi-metallic constituents. The coordination of metal ions with polyalcohol in metal glycerate, as an intermediate template, is beneficial for achieving atomic blending of multiple metal ions in sulfides structure at HETMSs during the synthesis procedure. In reliance on the electronic and physicochemical traits, the electronic configuration of as-synthesized (CoFeNiMnCu)S 2 was elucidated by virtue of the comparison with its quaternary, ternary, and binary subsystems. The superior performance of np-HETMS (CoFeNiMnCu)S 2 nanoparticles, corresponding subsystems, and commercial RuO 2 catalyst are accentuated by integrating into a three-electrode configuration for OER reaction. The (CoFeNiMnCu)S 2 nanoparticles exhibited a trivial overpotential of 284 mV when the current density reached 10 mA/cm2 with a low Tafel slope of 57 mV/dec in a 1.0 M KOH solution. Besides providing a novel and highly active high-entropy-based electrocatalyst, this work inaugurates a new synthesis paradigm toward high-entropy metal alloys for extremely efficient electrocatalysis applications. [Display omitted] [ABSTRACT FROM AUTHOR]

• The Ti-2.7Al-2Fe-3Cu alloy depicts a full α/β lamellar structure, while the Ti-4Al-2Fe-3Cu alloy depicts an α/β lamellar structure together with continuous grain boundary α layers. Since Al is an α phase stabilizer, increasing Al content increases the amount of α phase in Ti-XAl-2Fe-3Cu alloys. • Increasing the Al content in Ti-XAl-2Fe-3Cu alloy from 2.7 to 4wt% increases the hardness, compressive strength and biocorrosion resistance of the alloy. • Ti-XAl-2Fe-3Cu alloys show a significantly higher polarization resistance and double layer capacitance because of the enveloping effect owing to the existence of a compact oxide layer. Ti-XAl-2Fe-3Cu (wt%) (X = 2.7,4) alloys were fabricated by extrusion of compacts of TiH 2 /Al/Fe/Cu powder blends. The microstructure and compressive and biocorrosion properties of the as-extruded rods were studied and compared to those of commercial pure (CP) Ti fabricated by extrusion of a TiH 2 powder compact under the same condition. The results show that the Ti-XAl-2Fe-3Cu alloy samples exhibit a significantly higher hardness and compressive yield strength than the CP Ti sample, and with increasing the Al content from 2.7 to 4 wt%, the compressive yield strength of the alloy increases from 1315 to 1422 MPa. The Ti-XAl-2Fe-3Cu alloy samples possess a better biocorrosion resistance than CP Ti, and the polarization resistance of the alloy increases with increasing Al content due to the reduced diffusion rate of corrosive ions through the surface oxide layers. Furthermore, with increasing the immersion time, the polarization resistance increases, and the double layer capacitance decreases. Overall the alloys show significantly better compressive strength and biocorrosion resistance than CP Ti, suggesting that they are more favorable than CP Ti for biomedical applications. [ABSTRACT FROM AUTHOR]