MgFe2O4 Nanoparticles Research Articles

Photocatalytic, antimicrobial and antibiofilm activities of MgFe2O4 magnetic nanoparticles

This study reports the antibacterial and antibiofilm activities of Magnesium ferrite nanoparticles (MgFe2O4) against gram-positive and gram-negative bacteria. The photocatalytic degradation of Carbol Fuchsin (CF) dye (a class of dyestuffs that are resistant to biodegradation) under the influence of UV-light irradiation is also studied. The crystalline magnesium ferrite (MgFe2O4) nanoparticles were synthesized using the co-precipitation method. The morphology of the resulting nanocomposite was examined using scanning electron microscopy (SEM), while transmission electron microscopy (TEM) was employed for further characterization of particle morphology and size. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) were utilized to analyze the crystalline structure, chemical composition, and surface area, respectively. Optical properties were evaluated using UV–Vis spectroscopy. The UV-assisted photocatalytic performance of MgFe2O4 nanoparticles was assessed by studying the decolorization of Carbol fuchsin (CF) azo dye. The crystallite size of the MgFe2O4 nanoparticles at the (311) plane, the most prominent peak, was determined to be 28.5 nm. The photocatalytic degradation of 10 ppm CF using 15 mg of MgFe2O4 nanoparticles resulted in a significant 96% reduction after 135 min at ambient temperature (25 °C) and a pH value of 9. Additionally, MgFe2O4 nanoparticles exhibited potent antibacterial activity against E. coli and S. aureus in a dose dependent manner with maximum utilized concentration of 30 µg/ml. Specifically, MgFe2O4 nanoparticles demonstrated substantial antibacterial activity via disk diffusion and microbroth dilution tests with zones of inhibition and minimum inhibitory concentrations (MIC) for E. coli (26.0 mm, 1.25 µg/ml) and S. aureus (23.0 mm, 2.5 µg/ml), respectively. Moreover, 10.0 µg/ml of MgFe2O4 nanoparticles elicited marked percent reduction in biofilm formation by E. coli (89%) followed by S. aureus (78.5%) after treatment. In conclusion, MgFe2O4 nanoparticles demonstrated efficient dye removal capabilities along with significant antimicrobial and antibiofilm activity against gram-positive and gram-negative bacterial strains suggesting their potential as promising antimicrobial and detoxifying agents.

Phase formation and dielectric properties of MgFe2O4 nanoparticles synthesized by hydrothermal technique

In the recent development of energy storage devices, the scientific study has demonstrated a significant interest in the applications of the magnesium iron oxide (MgFe2O4) nanoparticles. In this work, we present synthesized novel MgFe2O4 nanoparticles at different molarities (0.1–0.5 M), via hydrothermal technique. An X-ray Diffractometer was used to study the phase analysis of the prepared samples at different molarities. A pure cubic phase of the MgFe2O4 is observed at molar concentrations of 0.3 M and 0.4 M. However, the mixed phases consisting of (MgFe2O4 + γ-Fe2O3) were also observed at 0.1 M, 0.2 M, and 0.5 M. The pure cubic MgFe2O4 nanoparticles depict the large value of crystallite size, 19.5 nm, and the lowest dislocation density and strain. The vibrating Sample Magnetometer shows the ferromagnetic nature of the pure MgFe2O4 with a high saturation magnetization. The value of saturation magnetization surged from 36.88 emu/g to 55.2 emu/g at 0.4 M concentration. The dielectric response of the materials as a function of applied frequency was studied thoroughly by using an Impedance Analyzer. The highest value of dielectric constant and low tangent loss was also reported at 0.4 M. Cole-Cole plots are the affirmation of the contribution of both grains and grain boundaries in the charge mechanism. These distinctive features make the synthesized material an excellent choice for future spintronics and energy storage devices.

Synthesis of lithium doped magnesium ferrites and their vibrational and magnetic properties: Correlation of experimental and density functional theory

Recently, there has been an increased focus on investigating the possible use of ferrite nanoparticles as magnetic memory devices. In this study, we report on the structural, microstructural, Raman, density functional theory and magnetic characteristics of Mg1-xLixFe2O4 (x = 0, 0.15, 0.3, 0.45, 0.5 and 0.75). Samples were synthesized by solution combustion synthesis method. Samples were subjected to characterize X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Raman Spectra. XRD reveals that all synthesized samples show a single phase formation and unit cell volume, crystallite size varied with an increase in Lithium-ion concentration. SEM micrographs confirmed the porous nature increases with the rise of Li concentration. Particles are agglomeration and spherical type of nature was confirmed by TEM images. Further, Raman Spectra confirms the spinel cubic structure of MgFe2O4 nanoparticles belongs to the Fd3m space group. Despite the fact that the full unit cell has 56 atoms (Z = 8), the smallest Bravais cell consists of only 14 atoms (Z = 2). Consequently, in order to understand this effect, the electronic structure of pure and doped models was investigated through the Band Structure and Density of States (D.O.S.) profiles. First the crystalline structure of pure and Li-doped MgFe2O4 was analyzed based on the optimized lattice parameters and M − O (M = Mg, Li and Fe) bond distances. The band-gap was computed to be 2.54 eV being a direct transition between two points, in an excellent agreement with the experimental measurements. To investigate the temperature dependent magnetic properties, the M − H loops of Li doped MgFe2O4 nanoparticles traced at below and above room temperature over the applied magnetic field ±60 kOe. The M − H loops recorded at above and below room temperature demonstrated that the ferromagnetic nature of the sample. Further, the magnetic properties was investigated using temperature dependent FC and ZFC magnetization measurements. Above room temperature, the ZFC and FC curves show irreversibility and split at certain temperatures, as well as a broad maximum in ZFC curves at blocking temperature (TB). Saturation magnetization (Ms) values are higher at 15 K compared to 300 K, attributed to reduced thermal fluctuation. Our results suggest that synthesized materials are useful for room temperature magnetic memory device application.

Poly(O‐Toluidine)‐polyvinylpyrrolidone copolymer submerged MgFe2O4/CS‐OXSWCNTs nanocomposite for removal of acid red dye from aqueous solutions

AbstractIn this study, a new hybrid material was created that exhibits excellent adsorption performance and high stability. POT‐PVP/MgF/CS‐OXSWCNTs NCs were synthesized using a three‐step approach. The process involved the chemical polymerization of poly(o‐toluidine)‐polyvinylpyrrolidone (POT‐PVP) with MgFe2O4 nanoparticles (MgF NPs) and chitosan‐oxidized single‐wall carbon nanotubes (CS‐OXSWCNTs). The synthesis process involved the use of an egg white method to synthesize MgF NPs and cross‐linking chitosan with OXSWCNTs using glutaraldehyde (GA) to obtain CS‐OXSWCNTs. The POT‐PVP copolymer was then used to coat MgF NPs and CS‐OXSWCNTs NCs. The successful synthesis of the NCs with strong component interaction was confirmed by several characterization techniques, including X‐ray diffraction spectroscopy (XRD), Fourier‐transform infrared spectroscopy (FTIR), and Raman spectroscopy. Microscopy analysis using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) verified that the POT‐PVP copolymer had properly coated the MgF NPs and CS‐OXSWCNTs NCs. The N2 adsorption–desorption isotherm verified that the specific surface area of NCs had increased with the addition of MgF NPs and CS‐OXSWCNTs NCs. Furthermore, the composite structure greatly improved the thermal stability of POT‐PVP/MgF/CS‐OXSWCNTs NCs. To evaluate how well the nanocomposites (NCs) eliminated pollutants, an artificially produced toxic effluent that contained acid red dye (A.R) was applied. To investigate their impact on dye removal, several parameters were changed, including pH, adsorbent dosage, time, temperature, and ionic strength. The POT‐PVP/MgF/CS‐OXSWCNTs NCs showed a higher removal rate based on a greater surface area, stability, and conducting power than MgF NPs and POT‐PVP. It was found that 25 mg L−1 and 7.5 mg were the optimal dye concentration and adsorbent dosage, respectively. The POT‐PVP/MgF/CS‐OXSWCNTs NCs achieved 99.46% removal efficiency at an acidic pH of 2. The NCs were found to have a maximum dye adsorption capacity of 107.4 mg g−1, and the adsorption process followed the pseudo‐second‐order kinetics. Thermodynamic analyses revealed that the dye adsorption onto POT‐PVP/MgF/CS‐OXSWCNTs NCs was endothermic, implying a spontaneous and physical adsorption mechanism. It can be inferred from these results that POT‐PVP/MgF/CS‐OXSWCNTs NCs are useful for eliminating dye pollutants from water.

Tecoma stans floral extract-mediated synthesis of MgFe2O4/ZnO nanoparticles for adsorption and photocatalytic degradation of coomassie brilliant blue dye.

Toxic organic dyes-containing wastewater treatment by adsorption and photocatalytic techniques is widely applied, but adsorbents and photocatalysts are often synthesized through chemical methods, leading to secondary pollution by released chemicals. Here, we report a benign method using Tecoma stans floral extract to produce MgFe2O4/ZnO (MGFOZ) nanoparticles for adsorption and photocatalytic degradation of coomassie brilliant blue (CBB) dye. Green MGFOZ owned a surface area of 9.65 m2/g and an average grain size of 54 nm. This bio-based nanomaterial showed higher removal percentage and better recyclability (up to five cycles) than green MgFe2O4 and ZnO nanoparticles. CBB adsorption by MGFOZ was examined by kinetic and isotherm models with better fittings of Bangham and Langmuir or Temkin. RSM-based optimization was conducted to reach an actual adsorption capacity of 147.68 mg/g. Moreover, MGFOZ/visible light system showed a degradation efficiency of 89% CBB dye after 120 min. CBB adsorption can be controlled by both physisorption and chemisorption while •O2- and •OH radicals are responsible for photo-degradation of CBB dye. This study suggested that MGFOZ can be a promising adsorbent and catalyst for removal of organic dyes in water.

Isotherm, kinetic and thermodynamic modelling of liquid phase adsorption of the heavy metal ions Zn(II), Pb(II) and Cr(VI) onto MgFe2O4 nanoparticles

MgFe2O4 nanoparticles are synthesized by sol-gel method and the adsorption characteristics of these nanoparticles on the removal of Zn(II), Pb(II) and Cr(VI) ions from their aqueous solutions are analysed. The samples are characterized by X-ray powder diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and Raman Spectroscopy. Batch adsorption studies are carried out to investigate the effect of adsorption parameters such as adsorbent dose, pH, temperature, contact time and initial ion concentration. The feasibility and spontaneity of the adsorption process is checked by thermodynamic analysis. Four adsorption kinetics models viz. Pseudo first-order, Pseudo second-order, Intra particle diffusion and Elovich model and four adsorption isotherm models viz Langmuir, Freundlich, Dubinin-Radushkevich (D-R), and Temkin isotherm models are studied and employed to model the adsorption equilibrium data. All the kinetics and isotherm parameters including rate constants and maximum adsorption capacity are determined and compared. The adsorption process best fits the Pseudo-second-order kinetics model and Langmuir adsorption isotherm model. Of the three heavy metal ions studied, the adsorption of Zn(II) ions by MgFe2O4 nanoparticles exhibits the best performance, followed by Pb(II) and Cr(VI) ions respectively. By regenerability study, the extent of reuse of the MgFe2O4 nanoparticles is checked.

Manipulating the phase and morphology of MgFe2O4 nanoparticles for promoting their optical, magnetic, and microwave absorbing/shielding characteristics

Morphology and phase regulation shed light on the tuning of microwave absorbing characteristics, as well as magnetic and optical features. Not only is the development of electromagnetic wave absorbing materials the best way to equip us against harmful electromagnetic waves in the technology era, but the widespread applications of microwave absorbers in military and civilian fields have also enhanced their importance. Hence, MgFe2O4 nanoparticles were synthesized, and then (1) its main crystalline phase was divided into Mg, Fe2O3, and Fe3O4, and (2) its morphology was manipulated to evaluate the influence of morphology and phase on the microwave absorbing performance, optical characteristics, and magnetic capability. The novel precursors, along with modified sol-gel and solvothermal scenarios, were applied to regulate the structures toward strengthening the features. Interestingly, polyethylene terephthalate (PET) was chosen as the recyclable plastic to fabricate the final composites to evaluate the microwave absorbing/shielding characteristics due to its fascinating susceptibilities as building materials, minimizing environmental hazards and implementing green and sustainable manufacturing. Noticeably, Mg/Fe3O4/PET nanocomposite gained a brilliant RL of −95.50 dB at 21.80 GHz meanwhile the one-pot-synthesized Fe2O3/MgFe2O4 composited by PET attained a maximum RL of −71.32 dB at 23.06 GHz and an ultra-high efficient bandwidth (RL ≤ −20 dB) of 8.50 GHz with only thickness of 0.50 mm. Interestingly, the PET-based microwave absorbers were fabricated with a low filling ratio of 10 wt%. More significantly, the samples illustrated proper shielding efficiency, desirable for practical applications in the modern era.

Effect of Nonthermal Plasma on Cation Distribution and Photocatalytic Activity of MgFe2O4 Nanoparticles for Dye Degradation Application

Nanophotocatalysts are becoming increasingly popular for removing heavy metals from wastewater, degrading organic pollutants, and producing hydrogen. In this work, MgFe2O4 nanoparticles were prepared by a sol‐gel process to study the photocatalytic degradation of crystal violet (CV), rhodamine blue (RhB), and methylene blue (MB) dyes under sunlight irradiation. The prepared MgFe2O4 nanoparticles were calcined at 500°C and then treated with nonthermal microwave plasma for 60 min. The X‐ray diffraction (XRD) analysis revealed that the crystallinity of plasma‐treated MgFe2O4 nanoparticles increased by showing a different cation distribution compared with plasma‐treated nanoparticles based on the intensity ratios of (220), (400), and (420) diffraction peaks. The intensity ratios of XRD peaks decreased, and the lattice parameter increased after plasma treatment. Crystallite size also increases after plasma treatment. The optical band gap energy of the treated ferrites decreased from 2.21 eV to 2.17, showing increased light absorption in the visible region compared with pristine ferrites. The saturation magnetization of magnetic photocatalysts increased from 40.9 emu/g to 62.16 emu/g after plasma modification. The photocatalytic activity for CV, RhB, and MB degradation increased from 60%, 65%, and 53% to 90%, 91%, and 87% after plasma modification. Plasma treatment enhances dye degradation by promoting the formation of reactive species that can effectively break down the dye molecules.

Simultaneous optimization of production yield and sulfadiazine adsorption of MgFe2O4 loaded on prickly pear biochars using Box-Behnken design.

A major challenge that humans facing is the uncontrolled discharge of antibiotic-containing wastewater into the environment, accompanying with huge threats to human community. The utilization of cost-effective biomass-based adsorbents is considered a potential solution for the treatment of antibiotic wastewater. This study aims to optimize the synthesis of MgFe2O4 nanoparticles loaded on prickly pear biochar (PPB) with outstanding sulfadiazine adsorbability using response surface methodology. Thirteen materials (MgFe2O4-PPB) produced based on Box-Behnken design were tested to evaluate the impact of the main factors on the material preparation process, including ratio of MgFe2O4:PPB precursors, calcination temperature and calcination time. Under optimized conditions, i.e., MgFe2O4:PPB ratio 0.5, temperature 600 °C and time 1 h, the production yield of 46.5% and sulfadiazine removal percentage of 85.4% were obtained. Characterization of optimized MgFe2O4-PPB indicated the good porosity and functionality suitable for the adsorption of sulfadiazine. Elovich model showed the best description of kinetic process. Temkin model was considered to be an accurate description of the isotherm adsorption. Proposed mechanism for antibiotic adsorption onto MgFe2O4-PPB was described. We clarify cost-benefit analysis to asses the importance of MgFe2O4-PPB as well as the economic and environmental impacts of biochar-based composites.

Synthesis and characterization of magnesium zinc ferrite nanoparticles for catalytic hydrogen evolution

We have prepared Mg1-xZnxFe2O4 nanoparticles (x values varying from 0.0 to 0.8 by 0.2 increments) for use as catalysts for hydrogen production in the methanolysis of sodium borohydride (NaBH4). The catalytic performance of the Mg1-xZnxFe2O4 nanoparticles with different zinc content for hydrogen production were evaluated in the methanolysis of NaBH4 inside glass vessels. Different characterization techniques were used to analyse the prepared nanoparticles such as X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FTIR), Field Emission Scanning Electron Microscope (FESEM), Transmission Electron microscopy (TEM), and Scanning Transmission Electron microscopy STEM. The average size of Mg1-xZnxFe2O4 nanoparticles was 10 nm. The largest energy band gap value was 4.77 eV for MgFe2O4 nanoparticles, while the lowest value was 2.89 eV for Mg0.2Zn0.8Fe2O4 nanoparticles. Mg0.8Zn0.2Fe2O4 nanoparticles were proven as the catalysts with the highest hydrogeneration rate with a value of 15,957 mL min−1 g−1.

Facile Fabrication of High-Performance Superhydrophobic Reusable Oil-Absorbing Sponges

Wastewater treatment from oil, oil products and organic mixtures is a very relevant topic that can be successfully utilized to solve problems of severe environmental pollution, such as oil spills, industrial oily wastewater discharges and water treatment in the water treatment process. In this work, we have developed new superhydrophobic magnetic polyurethane (PU) sponges, functionalized with reduced graphene oxide (RGO), MgFe2O4 nanoparticles, and silicone oil AS 100 (SO), as a selective and reusable sorbent for the purification and separation of wastewater from oil and organic solvents. The surface morphology and wettability of the sponge surface were characterized by scanning electron microscopy (SEM) and a contact angle analysis system, respectively. The results showed that the obtained PU sponge PU/RGO/MgFe2O4/SO had excellent mechanical and water-repellent properties, good reusability (lasted more than 20 cycles), as well as fast (immersion time 20 s) and excellent absorption capacity (16.61–44.86 g/g), and additional good magnetic properties, which made it easy to separate the sponge from the water with a magnet. The presence of RGO in the composition of the nanomaterial improves the separating and cleaning properties of the materials and also leads to an increase in the absorption capacity of oil and various organic solvents. The synthesized PU sponge has great potential for practical applications due to its facile fabrication and excellent oil–water separation properties.

A comparative study on the malachite green dye adsorption of chemically synthesized and green MgFe2O4 nanoparticles using gerbera floral waste extract.

The situation of discharging a large amount of dyes from the textile industries has caused many adverse effects on human health and the ecosystems. Emerging bio-nanomaterials represent a new trend in efficient dye removal in aqueous media. Herein, we mention that MgFe2O4 bioprepared using gerbera extract has been successfully used to adsorb malachite green (MG) in water. A comparison was made to determine the dye removal efficiency between biogenic MgFe2O4 (MFOB) and chemical MgFe2O4 (MFOC). The spherical MFOB material exhibited a large surface area of 85.0 m2 g-1 and high crystallinity. The obtained outcomes showed that the highest adsorption capacity of MG dye was 584.49 mg g-1 at a MFOB dose of 0.05 g L-1 and MG concentration of 10 mg L-1. Higher correlation coefficients in the Langmuir isotherm suggested monolayer adsorption of MG. The Box-Behnken design and response surface method were established to optimize MG removal percentage under the conditions, i.e., initial MG concentration (10-30 mg L-1), adsorbent dose (0.02-0.08 g L-1), and pH of dye solution (6-8). MFOB had good reusability with high removal efficiencies after three continuous cycles. Post reuse, this adsorbent still showed excellent stability through the verification of their structural properties in comparison with fresh MFOB, showing potential for practical applications.

Synthesis of 3-Aminoalkylated Indoles Using Heterogeneous MgFe2O4 Nanoparticles Under Microwave Irradiation in One-Pot Three-Component System

AbstractA series of 3-aminoalkylated indoles are efficiently synthesised in a one-pot three-component reaction under microwave irradiation. Magnesium ferrite (MgFe2O4) nanoparticles (10 mol%) have been used as heterogeneous catalyst, which may easily be recovered by application of an external magnet and the recovered catalyst can be reused at least for five runs without affecting the efficiency of the catalyst. The solvent-free protocol developed has advantages of less reaction time, high yields, and easy workup, and the protocol is applicable to various acid base sensitive functional groups present in the substrate. The reported methodology is highly suitable especially for primary amines in addition to secondary amines as one of the components.

MgFe2O4Nanoparticle/Peracetic Acid Hybrids for Catalytic Oxidative Depolymerization of Lignin

Lignin is a promising feedstock for renewable fuels and chemicals due to its aromatic skeleton and natural abundance. Lignin can be converted to diverse aromatic monomers as well as dicarboxylic acids depending on the applied conversion technologies. Despite its great potential, its native and processing-induced heterogeneity and complexity limit the conversion efficiency and product selectivity. In this study, magnesium ferrite (MgFe2O4) nanoparticle–peracetic acid (PAA) has been investigated as an efficient catalyst–oxidant incorporation for catalytic oxidative depolymerization of lignin under mild conditions. Typically, the increase in processing severity can enhance the lignin conversion while it results in the further decomposition of aromatic compounds to dicarboxylic acids. However, in this study, the incorporation of MgFe2O4 nanoparticles and PAA not only enhanced the total product yield but also improved the selectivity of aromatic monomers. The oxidative depolymerization system using the catalyst–oxidant combination resulted in 46 wt % of total oil product with a 61% selectivity of aromatic monomers under mild temperature (90 °C). In addition, this combination catalyst showed relatively good cycling stability based on the total product yield after recycling five times via magnetic separation. Overall, MgFe2O4 nanoparticles play an important role as a co-catalyst with a PAA oxidant in the oxidative conversion of lignin with an enhanced conversion efficiency and recyclability, and it will facilitate the valorization of lignin in future bio-based fuels and chemicals.

Influence of NaCl on Magnetic Properties of MgFe2O4 Nanoparticles Synthesized by Gel Combustion

Influence of NaCl on Magnetic Properties of MgFe2O4 Nanoparticles Synthesized by Gel Combustion

Combining the bioelectricity generation with Photo-Electrocatalytic reduction of CO2 for pollutants degradation and ethanol generation

Under this investigation, a p-n heterojunction nanocomposite (CuS/MgFe2O4) was synthesized using a simplified hydrothermal technique. According to the results of UV–vis diffuse reflectance spectroscopy (DRS) research, the creation of a p-n heterojunction structure lowered the band-gap value and improved the optical characteristics of the synthesized CuS/MgFe2O4 nanocomposite in contrast to CuS and MgFe2O4 nanoparticles. To investigate the electrocatalytic and photo-electrocatalytic properties of nanoparticles in the CO2 reduction reaction, first, the synthesized catalysts were immobilized by the electrophoretic deposition method (EPD) on a graphite electrode, and then various electrochemical techniques such as cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) were performed in the phosphate electrolyte (0.1 M, pH = 8) saturated with CO2 gas in the presence and absence of light. As a consequence, CuS/MgFe2O4/Graphite displayed a 2.2 and 1.3-fold increase in cathodic current density under light illumination compared to MgFe2O4/Graphite and CuS/Graphite, respectively. Using CuS/Graphite, MgFe2O4/Graphite, and CuS/MgFe2O4/Graphite as photocathodes in a two-chamber microbial fuel cell (MFC) caused a 13, 29, and 45 times increase, respectively, in the maximum power density compared to unmodified graphite. Gas chromatography-mass spectrometry (GC–MS) analysis revealed the presence of ethanol as the only detected CO2 conversion product, with a Faradic efficiency of about 35 %.

Remarkable High Adsorption of Methylene Blue Dye from Aqueous Solutions Using Facilely Synthesized MgFe2O4 Nanoparticles

Remarkable High Adsorption of Methylene Blue Dye from Aqueous Solutions Using Facilely Synthesized MgFe2O4 Nanoparticles

Electrochemical investigation on nickel-doped spinel magnesium ferrite nanoparticles for supercapacitor applications

Due to their extensive cycle life, significant power storage capacity, and quick recharge ability, electrochemical (EC) capacitors, namely supercapacitors (SCs), have attracted great interest from the scientific community. Recent research has shown transition metal oxides as the best material for the considerable performance of flexible SCs. X-ray diffractometer (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive spectroscopy (EDS) mapping, electron spin resonance (ESR) and Brunauer-Emmett-Teller (BET) studies were used to methodically characterize the synthesized Ni-doped MgFe2O4 nanoparticles. The typical size range of the nanoparticles is 8–11 nm. In 1 M KOH solution, the produced Ni0.35Mg0.65Fe2O4 (code as: NM3) electrode has been used as a pseudocapacitor, revealing an extraordinary specific capacitance of 119.04 F/g at a current density (CD) of 1.1 A/g compared to Ni0.15Mg0.85Fe2O4 (code as: NM1) and Ni0.25Mg0.75Fe2O4 (code as: NM2) electrodes. The electrochemical impedance spectra (EIS) were used to determine the electrode's EC properties. These findings indicate the potential use fullness of Ni-doped MgFe2O4 nanoparticles for SCs applications.

Effect of MgFe2O4 catalyst preparation method on its surface characteristics and Fenton-like oxidation of tartrazine: Statistical comparison and DFT-assisted predation of mechanism

In this study, MgFe2O4 nanoparticles fabricated by co-precipitation (MgF-Cop) and sol-gel auto-ignition (MgF-SG) methods were applied in a Fenton-like process for the degradation of Tartrazine (TA) dye. XRD, FTIR, SEM, and EDX techniques were used to characterize the nanoparticles. Our aim is to compare the relative characteristics of catalysts synthesized by two different methods and to investigate which combinations resulted in better catalytic activity. The interactions between three operating parameters, including catalyst dosage, hydrogen peroxide concentration, and initial TA concentration, were evaluated by employing the Box–Behnken design. The optimal TA removal efficiency D (%) conditions were as follows: catalyst dosage of 0.1 g/L, initial H2O2 dosage of 229 mg/L, and initial TA concentration of 30 mg/L. D (%) achieved on this condition were 79.9% and 98.0% within 60 min for MgF-Cop and MgF-SG, respectively. The co-precipitation method yields a slightly less active catalyst with a lower crystallinity than the sol-gel auto-ignition method. Molecular dynamic (MD) simulations and density functional theory were applied to study the adsorption mechanism and the possible degradation mechanism of TA dye, respectively. The positive total energy calculated indicates that TA has almost no adsorption on the MgFe2O4 nanoparticles. The quantum parameters show that the dye is more reactive and has many sites for HO• radical attack. The Theoretical results correlated with the experimental findings.

Cu(ii) immobilized on poly(guanidine-sulfonamide)-functionalized Bentonite@MgFe2O4: a novel magnetic nanocatalyst for the synthesis of 1,4-dihydropyrano[2,3-c]pyrazole.

In this paper, we aim at synthesizing a new nanocomposite material in which bentonite acts as a nucleation site for MgFe2O4 nanoparticles precipitation in the attendance of an external magnetic field (MgFe2O4@Bentonite). Moreover, poly(guanidine-sulfonamide), as a novel kind of polysulfonamide, was immobilized on the surface of the prepared support (MgFe2O4@Bentonite@PGSA). Finally, an efficient and environment-friendly catalyst (containing nontoxic polysulfonamide, copper, and MgFe2O4@Bentonite) was prepared by anchoring a copper ion on the surface of MgFe2O4@Bentonite@PGSAMNPs. The synergic effect of MgFe2O4 magnetic nanoparticles (MNPs), bentonite, PGSA, and copper species was observed while conducting the control reactions. The synthesized Bentonite@MgFe2O4@PGSA/Cu, which was characterized using energy-dispersive X-ray spectroscopy (EDAX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Fourier-transform infrared (FT-IR) spectroscopy, was applied as a highly efficient heterogeneous catalyst to synthesize 1,4-dihydropyrano[2,3-c] pyrazole yielding up to 98% at 10 minutes. Excessive yield, quick reaction time, using water solvent, turning waste to wealth, and recyclability are the important advantages of the present work.