Solvent Method Research Articles

New insight into the photocatalytic degradation of organic pollutant over BiVO4/SiO2/GO nanocomposite

The nanocomposite of BiVO4-based material has been synthesized by one-step solvent method. The morphological, physical, chemical properties of the nanocomposite have been investigated. The results revealed that the surface area of BiVO4, BiVO4/SiO2 and BiVO4/SiO2/GO was 11.13, 28.47 and 43.93 m2/g, respectively. The structural test by XRD proved that the nanocomposites were monoclinic phase of bismuth vanadate. Adsorption and photocatalytic degradation were two main mechanisms that strongly related to pollutant removal efficiency (i.e., methylene blue and phenol). The BiVO4/SiO2/GO nanocomposite obtained the greatest MB removal efficiency due to its high adsorption ability from high surface area, whereas the photocatalytic degradation was insignificant mechanism. In contrast, the relatively low adsorption ability of BiVO4/SiO2/GO nanocomposite was observed when the pollutant was phenol due to negative charge and high stability of phenoxide ions, then the photocatalytic degradation became the main mechanism for phenol removal. The phenol removal efficiency reached approximately 70% in 6 h with H2O2 assistance. The combination of SiO2 and GO improved the surface property of BiVO4-based photocatalyst, however the excessive combination ratio generated the excellent adsorbent material rather than the photocatalyst. Hence, the optimal combination ratio is essential to archive the greatest nanocomposite for photocatalytic application.

Metal-organic frameworks derived hierarchical CoSx@Ni-Co-O nanosheet structures for supercapacitors with excellent charge storage properties

Abstract The composite of multiple metal materials is an effective means of improving the electrochemical performance of supercapacitors, however the synergistic effect of composites is currently facing challenges. In this work, the metal-organic framework was constructed by a simple solvent method to synthesize the Co-MOF and the CoSx material was derived by sulfidation. Subsequently, Ni–Co–O nanosheets were deposited on the above structures by electrodeposition. The Ni–Co–O nanosheets were grown on the CoSx surface to build cross-linked structures, while maintaining the structural stability, the conductivity and reaction site of the material are improved, and the ion transport is accelerated. The synergistic effect of both materials CoSx and Ni–Co–O effectively improves the specific capacity of the material (899 C g−1 at 1 A g−1). In addition, the assembled asymmetric supercapacitors show a high energy density 42.43 kW kg−1 at a power density of 0.725 kW h kg−1 as well as an excellent cycle stability (83.73% capacity retention after 3000 cycles).

Expanding the Toolbox for Peptide Disulfide Bond Formation via l-Methionine Selenoxide Oxidation.

In this study, l-methionine selenoxide (MetSeO) was used as an oxidant for the construction of peptide disulfide bonds. Excellent yields for various disulfide-containing peptides were achieved via the MetSeO oxidation method in different solvents and on a resin. Most importantly, the construction of disulfide bonds can be performed in the trifluoroacetic acid cocktail used for the cleavage of peptides from the resin, which obviates the steps of peptide purification and lyophilization. This facilitates and simplifies the synthesis of disulfide-containing peptides. Kinetic and mechanistic studies of the reaction between MetSeO and dithiothreitol (DTT, a model compound of dicysteine-containing peptide) show that the reaction is first order in both [MetSeO] and [DTT], and a reaction mechanism is proposed that can help us gain insights into the reaction of the oxidative synthesis of disulfide bonds via MetSeO oxidation.

In Vitro Characterization of Inhalable Cationic Hybrid Nanoparticles as Potential Vaccine Carriers.

In this study, PGA-co-PDL nanoparticles (NPs) encapsulating model antigen, bovine serum albumin (BSA), were prepared via double emulsion solvent evaporation. In addition, chitosan hydrochloride (CHL) was incorporated into the external phase of the emulsion solvent method, which resulted in surface adsorption onto the NPs to form hybrid cationic CHL NPs. The BSA encapsulated CHL NPs were encompassed into nanocomposite microcarriers (NCMPs) composed of l-leucine to produce CHL NPs/NCMPs via spray drying. The CHL NPs/NCMPs were investigated for in vitro aerosolization, release study, cell viability and uptake, and stability of protein structure. Hybrid cationic CHL NPs (CHL: 10 mg/mL) of particle size (480.2 ± 32.2 nm), charge (+14.2 ± 0.72 mV), and BSA loading (7.28 ± 1.3 µg/mg) were produced. The adsorption pattern was determined to follow the Freundlich model. Aerosolization of CHL NPs/NCMPs indicated fine particle fraction (FPF: 46.79 ± 11.21%) and mass median aerodynamic diameter (MMAD: 1.49 ± 0.29 µm). The BSA α-helical structure was maintained, after release from the CHL NPs/NCMPs, as indicated by circular dichroism. Furthermore, dendritic cells (DCs) and A549 cells showed good viability (≥70% at 2.5 mg/mL after 4–24 h exposure, respectively). Confocal microscopy and flow cytometry data showed hybrid cationic CHL NPs were successfully taken up by DCs within 1 h of incubation. The upregulation of CD40, CD86, and MHC-II cell surface markers indicated that the DCs were successfully activated by the hybrid cationic CHL NPs. These results suggest that the CHL NPs/NCMPs technology platform could potentially be used for the delivery of proteins to the lungs for immunostimulatory applications such as vaccines.

Dispersi Padat untuk Peningkatan Laju Disolusi Natrium Diklofenak dengan Variasi Konsentrasi Polivinil Pirolidon K30

Diclofenac sodium is included in the class II category based on the biopharmaceutics classification system (BCS), sodium diclofenac has low solubility and high permeability. Low solubility will affect the absorption of drugs in the body because the rate of dissolution will decrease. Polyvinyl Pyrrolidone (PVP) K30 is an inert carrier that dissolves easily in water and can affect the solubility of an active drug substance. To know solid dispersion system increasing dissolution rate of sodium diclofenac by adding variations concentration of PVP K30. Solid dispersion uses a solvent method with variations concentration of PVP K30 1:3, 1:5, 1:7, and 1:9. Test physical properties of solid dispersions using a moisture test and compressibility. Solid dispersion dissolution test using type 2 dissolutions test and determination of concentration using UV-VIS spectrophotometry. Test results were analyzed using One Way ANOVA and continued test. Solid dispersion has a good physical whit moisture percentage not >5% and compressibility not >20%. Solid dispersion of sodium diclofenac with the addition of PVP K30 can increase dissolution rate compared to pure sodium diclofenac (p<0,05) with the highest ratio 1:7. Each comparison has a significant difference (p<0,05) except in ratio 1:9. Solid dispersion of sodium diclofenac with PVP K30 can increase the dissolution rate of pure sodium diclofenac.

Granularity control enables high stability and elevated-temperature properties of micron-sized single-crystal LiNi0.5Mn1.5O4 cathodes at high voltage

The development of high energy density LiNi0.5Mn1.5O4 (LNMO) cathode materials for lithium-ion batteries are challenged by capacity degradation, which becomes more aggravated particularly at elevated temperatures. Thus, the practical strategy with facile craft and the viability of large-scale preparation for industrialized applications should be developed urgently. In this work, a micron-sized LNMO single crystals is synthesized by a facile two-step method consisting of an alcohol gel solvent method and a segmented sintering reaction. Results show that the truncated polyhedron LNMO-900 sample, with the moderate D50 characteristic value of 4.429 μm and the highest tap density of 2.31 g cm−3, provides a stable structural and chemical stability even at elevated testing temperature due to its moderate specific surface area and the few Fd-3m phase. The LNMO/Li half-cells display more excellent capacity retention (87.3% at 1C and 25 °C after 500 cycles) and better thermal stability (76.65% at 1C and 55 °C after 200 cycles) than those of the single crystals of LNMO-850 and LNMO-950. Besides, the XPS, in-situ EIS and electrochemical tests results also prove that the LNMO-900 exhibits the lowest electrolyte decomposition degree, owing to a thin and effective solid-electrolyte interfacial film formed after cycles.

An Investigation of the Recovery of Silicon Photovoltaic Cells by Application of an Organic Solvent Method

The treatment of photovoltaic (PV) waste is gaining traction the world over, with the recovery of valuable materials from end-of-life, or damaged and out-of-spec polycrystalline silicon PV modules. These materials are a focus of recycling. However, the current recycling practices usually involve excessive damage to PV cells that could otherwise be reused if recovered undamaged. The ability to recover undamaged PV cells, capable of reuse, would serve to further reduce the carbon footprint and cost associated with PV module manufacturing. This study focuses on the recovery of silicon PV cells from end-of-life PV modules by application of an organic solvent method. Herein, recovery tests were carried out in which silicon PV cells were recovered with minimal damage with the application of hexane as solvent. X-ray diffraction and UV–vis spectrophotometry measurements were conducted post recovery of the PV cells. The results from this study shows that the recovery of PV cells from application of hexane as the solvent could be an eco-friendly and benign approach to purse towards a strategic pathway for extending the life of recycled PV modules.

Solvothermal sol–gel synthesis of TiO2-cellulose nanocrystalline composites

Due to its unique supramolecular structure, cellulose is widely used as a template agent, ensuring an easy structuring of anatase TiO2 particles with subsequent release after the organics burning. This work is devoted to the synthesis of microcrystalline cellulose-TiO2 (MCC-TiO2) composite photocatalyst by preserving the intermediate organic–inorganic structures. A series of the MCC-TiO2 materials were prepared via solvothermal sol–gel method in n-decane and caproic acid solvents and characterized by X-ray diffraction, transmission electron microscopy, IR spectroscopy, 1H NMR and TG/DSC methods. The photocatalytic activity of the prepared materials was evaluated by the decomposition of formic acid in aqueous solutions. The composites failed to be formed in n-decane, while in caproic acid, acting as solvent and reagent, anatase TiO2 nanoparticles were formed onto the crystalline domains of cellulose, tightly fixed due to covalent Ti–O–C bonds. The materials formed in caproic acid showed a higher photocatalytic activity, explained by a complementarity of the organic and inorganic components. The specific activity (normalized on TiO2 mass) of best synthetized composite materials was almost twice higher than that of Aeroxide P25 TiO2 reference photocatalyst.

Preparation of 0–2 dimensional organic-decorated quaternary TM-Cd-Sb-Se (TM = Zn, Mn, Fe) compounds by solvothermal method: Syntheses, crystal structures and properties

Three organic-decorated quaternary TM-Cd-Sb-Se (TM ​= ​Zn, Mn, Fe) compounds were prepared under tris (2-aminoethyl) amine conditions by solvent method, namely, [Zn(tren)]2CdSb2Se6 (1), [Mn(tren)]CdSb2Se5 (2) and [Fe(tren)]Cd2SbSe5 (3) [tren ​= ​tris (2-aminoethyl) amine)]. The single-crystal X-ray diffraction analyses showed that the three compounds structures were 0-D {[Zn(tren)]2CdSb2Se6} (1) cluster, 1-D {[Mn(tren)]CdSb2Se5} (2) ribbon and 2-D {[Fe(tren)]Cd2SbSe5} (3) layered. A series of characterizations of these compounds were performed, as estimated from the adsorption spectra, the band gaps of 1, 2 and 3 are 2.09, 1.78 and 1.91eV, respectively. Photoluminescence experiments show that compounds 2 and 3 exhibit luminescent properties. And the thermal stability of these compounds was tested by thermogravimetric and differential scanning calorimetry.

A novel three-step approach to separate cathode components for lithium-ion battery recycling

Lithium-ion batteries (LIBs) represent efficient energy storage technology that can help to alleviate fossil fuel-based CO2 emissions. Presently, LIBs are being applied extensively in consumer electronics and electric vehicles, but because of limited resources, there is an urgent need for spent LIB recycling technologies. The complexity of LIBs, especially the electrode part, makes it difficult to achieve precision separations for each single component from the used electrode with low emissions. Herein, we propose a three-step treatment for the separation of cathode components. In detail, detaching of the current collector from the cathode is accomplished by the solvent method, which was found to be an ideal strategy compared with previous reports. Then, a thermal treatment is used to remove the polymer binder in the second step because we demonstrated that it is challenging to separate polyvinylidene fluoride (PVDF) from other cathode components by dissolution with N-methylpyrrolidone. The separation efficiency between the active material and conductive carbon by the polymer solution in the third step showed reasonably good results. We anticipate this work will serve as an important reference for the separation of each single electrode component in both laboratory- and industrial-scale applications. Separation of binder and development of novel binders, which can be easily recycled for sustainable LIBs, are fruitful areas for further research.

SPION and doxorubicin-loaded polymeric nanocarriers for glioblastoma theranostics.

Glioma is a type of cancer with a very poor prognosis with a survival of around 15months in the case of glioblastoma multiforme (GBM). In order to advance in personalized medicine, we developed polymeric nanoparticles (PNP) loaded with both SPION (superparamagnetic iron oxide nanoparticles) and doxorubicin (DOX). The former being used for its potential to accumulate the PNP in the tumor under a strong magnetic field and the later for its therapeutic potential. The emulsion solvent and evaporation method was selected to develop monodisperse PNP with high loading efficiency in both SPION and DOX. Once injected in mice, a significant accumulation of the PNP was observed within the tumoral tissue under static magnetic field as observed by MRI leading to a reduction of tumor growth rate.

Anti-ulcer Effect of Gastroretentive Drug Delivery System of Alginate Beads Containing Turmeric Extract Solid Dispersion

BACKGROUND: Treatment of gastric ulcer using turmeric extract is less effective because curcumin has low solubility and degraded in alkaline intestinal pH. Therefore, it is necessary to convert turmeric extract into turmeric solid dispersion to increase the dissolution of curcumin and the preparation is made in gastroretentive drug delivery system to improve the absorption of curcumin in the stomach.
 AIM: The aim of the study was to determine the anti-ulcer effect of gastroretentive drug delivery system of alginate beads containing turmeric extract solid dispersion compared to alginate beads containing turmeric extract (without solid dispersion) and negative control.
 METHODS: Turmeric powder was macerated with 96% ethanol for 8 days. The macerate was evaporated with a rotary evaporator at 50°C to obtain a concentrated extract. Turmeric extract solid dispersion was prepared by the solvent method using polyvinylpyrrolidone as a carrier. The turmeric extract solid dispersion was encapsulated with alginate gel by gelation method. The antiulcer test was performed on rats with gastric ulcer that induced by 0.6 N HCl solution. The ulcer healing was observed macroscopically and microscopically (histopathology).
 RESULTS: The results of observation on the treatment of rats gastric ulcer that induced by 0.6 N HCl showed the gastroretentive drug delivery system of alginate beads containing turmeric extract solid dispersion effective in healing the gastric ulcer compared to negative control. The effectiveness was statistically significantly different (p < 0.05). Alginate beads containing turmeric solid dispersion were slightly more effective than alginate beads containing turmeric extract, but the effectiveness was not statistically significant (p > 0.05).
 CONCLUSION: Alginate beads containing turmeric extract solid dispersion were effective in treatment of gastric ulcer in rats.

Radiation-Induced Improving Mechanical and Thermal Properties of Carboxymethyl Cellulose/Clay Composite for Application in Removal of Copper(II) Ions from Wastewater

A study was carried out on the effect of gamma irradiation on the mechanical and thermal properties of carboxymethyl cellulose (CMC)/Ca-montmorillonite clay composite, prepared by blending using solvent method. In this study, carboxymethyl cellulose was used as a hosting matrix where clay was added to there at different contents: 0.25, 0.5, 1, 1.5 wt%, as a filler. The polymer composite films were cross-linked by irradiation with different integral doses. The results showed that the tensile strength (TS) increased continuously with radiation dose up to 10 kGy, beyond which declined. Meanwhile, TS exhibited increases with clay load ratio. However, the elongation at break (Eb) decreased continuously with dose and clay percentage within the developed composite films. Variation in structure and thermal properties were studied using X-ray diffractometion (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) techniques. The produced CMC/clay composites were implemented in removing copper (II) ions from a synthesized wastewater. The isotherm models and kinetic studies for the adsorption of Cu (II) onto CMC/clay were carried out. The results revealed that 0.1 g fabricated composite film irradiated at 10 kGy significantly removed copper (II) ions with adsorption capacity of 54.6 mg/g at optimum conditions: pH = 5, contact time = 300 min.

Impact of Two Different Methods of Extraction on Total Antioxidant Activity and Phenolic Content in an Uncommon Plant (Sansevieria trifasciata) and Commonly Consumed Fruits

To determine and compare total antioxidant activity (TAA) and phenolic content (TPC) of Sansevieria trifasciata leaves’ extract with different fruits’ extract (Guava, Indian plum and Indian gooseberry) and fruit juices (Pomelo, Orange, and Beetroot) on the basis of two extraction methods, total phenolic content and antioxidant activity were analysed by Folin-Ciocalteu’s and Phosphomolybdate assay, respectively and expressed as equivalent to catechin. The extraction process of selected samples was done by using both decoction extraction method (DEM) and microwave-assisted method (MAE) of water solvent. Among both techniques of extractions, MAE exhibited significantly higher TPC and TAA than DEM. Compared to Sansevieria trifasciata plant extracts, there was a strong positive correlation coefficient (á<0.05) between the total phenolic contents and antioxidant activities of different fruit juices and fruit extracts in both the classical (DEM) and modern (MAE) techniques. Sansevieria trifasciata possesses a considerable amount of phenolic compounds and antioxidant activity concerning different fruit juices and fruit extracts which directly associated with health-promoting potential and appears as possible drug development for antioxidant. Among all extract and juices, Indian gooseberry possesses the greatest total phenolic content and antioxidant activity due to its higher TPC.

Evaluation of different procedures for the extraction of phenolic compounds from a medicinal plant: Verbena officinalis

Since ancient times, plants have been the main source of bioactive molecules, such as phenolic compounds, capable of remedying various diseases. However, polyphenols' content and efficiency vary greatly as a function of several intrinsic and extrinsic factors. To optimize the procedure for the extraction of active molecules from the medicinal plant Verbena officinalis, effects of the plant origin, selected solvent, and extraction method were assessed. V. officinalis aerial parts were collected in two different regions of Tunisia (Bizerte and Ain Draham), and their bioactive molecules were extracted by maceration, decoction, and by the Soxhlet apparatus, either with water or with ethanol. Significant variability in the extracts' contents of phenolic compounds as well as their antioxidant and antimicrobial capacities were noted depending on the different studied factors. In particular, ethanol extracts were found to generally contain higher concentrations of phenolic compounds and more potent antioxidant capacities than water extracts. However, when tested against various pathogenic bacteria, water extracts were most often at least as active as ethanol extracts to inhibit bacteria growth in vitro. Finally, differences were also observed between V. officinalis samples from Bizerte compared to Ain Draham area. All of these results emphasize the need of adapting various parameters for the optimal extraction of bioactive molecules from a medicinal plant such as V. officinalis.

Synthesis and Characterization of Eu3+ + 2-thenoyltrifluoroacetone + triphenylphosphine Oxide Ternary Complex

Rare earth europium ion (Eu3+) can emit red characteristic fluorescence under UV excitation and is preferred for the preparation of red phosphors for near-UV white LEDs. In this paper, the effects of solvent, reflux time and preparation method on the preparation of europium ternary complexes were studied with europium ion as the central coordination ion, 2-thenoyltrifluoroacetone as the first ligand and triphenylphosphine oxide as the second ligand. The results showed that the better reaction solvent was anhydrous ethanol and the better reflux time was 8 hours. Both the common synthesis method and the solvothermal method could successfully synthesize the europium ternary complex, and the solvothermal method has a higher yield. The europium ternary complex was characterized by inductively coupled plasma emission spectroscopy, element analysis and infrared spectroscopy, and it was proved that the europium complex could emit a strong characteristic red fluorescence of europium with the structure of Eu(TTA)3(TPPO)2 in 1:3:2 coordination ratio.

Self-template-derived ZnCo2O4 porous microspheres decorated by Ag nanoparticles and their selective detection of formaldehyde

ZnCo2O4 porous microspheres were successfully synthesized through a facile one-step solvent method using polyethylene glycol 1000 as a self-assembly template and subsequent annealing.

Nanomaterial by Sol‐Gel Method: Synthesis and Application

The sol‐gel process is a more chemical method (wet chemical method) for the synthesis of various nanostructures, especially metal oxide nanoparticles. In this method, the molecular precursor (usually metal alkoxide) is dissolved in water or alcohol and converted to gel by heating and stirring by hydrolysis/alcoholysis. Since the gel obtained from the hydrolysis/alcoholysis process is wet or damp, it should be dried using appropriate methods depending on the desired properties and application of the gel. For example, if it is an alcoholic solution, the drying process is done by burning alcohol. After the drying stage, the produced gels are powdered and then calcined. The sol‐gel method is a cost‐effective method and due to the low reaction temperature there is good control over the chemical composition of the products. The sol‐gel method can be used in the process of making ceramics as a molding material and can be used as an intermediate between thin films of metal oxides in various applications. The materials obtained from the sol‐gel method are used in various optical, electronic, energy, surface engineering, biosensors, and pharmaceutical and separation technologies (such as chromatography). The sol‐gel method is a conventional and industrial method for the synthesis of nanoparticles with different chemical composition. The basis of the sol‐gel method is the production of a homogeneous sol from the precursors and its conversion into a gel. The solvent in the gel is then removed from the gel structure and the remaining gel is dried. The properties of the dried gel depend significantly on the drying method. In other words, the “removing solvent method” is selected according to the application in which the gel will be used. Dried gels in various ways are used in industries such as surface coating, building insulation, and the production of special clothing. It is worth mentioning that, by grinding the gel by special mills, it is possible to achieve nanoparticles.

Cu/ZnOx@UiO-66 synthesized from a double solvent method as an efficient catalyst for CO2 hydrogenation to methanol

The Cu precursor diffused into UiO-66 by the double solvent method is reduced by NaBH4 to form Cu nanoparticles. After introducing Zn2+, Cu/ZnOx@UiO-66 reduced by H2 is synthesized, which catalyzes the hydrogenation of CO2 to methanol efficiently.

Preparation and Characterisation of Biodiesel from Marine Macro-algae Chaetomorpha spp.

The petition for substitute energies has increased in the past numerous years. Several substitutes have come into existence in recent years, and many more are on their way to get established as a sustainable fuel substitute. In the present investigation, we carried out the extraction of total lipids and production of biodiesel from Chetomarpha spp., The algae were collected from the natural habitat of Karwar shoreline region. Different pre-treatment was adopted to dry the collected sample for lipid extraction. The solvent Method was followed to obtain biodiesel at laboratory conditions. GC-MS technique was followed to evaluate the composition of fatty acids in Extracted biodiesel. Quantity of total fatty acid (TFAs) accounted nearly normal in its lipid content composition as in many previous reports. Biofuel experiments have shown promising results towards biodiesel application. The same results have been explained in the appropriate form as given below.