FE-scanning Electron Microscopy Research Articles

Phytogenic Cu2OBi2O3ZrO2 nanomaterial for supercapacitor and water splitting: Synthesis, characterization, and energy applications

Copper-based nanocomposites are regarded as sustainable energy materials having tremendous potential for energy storage supercapacitors and energy generation water splitting applications. Herein, a facile Cu-based ternary Cu2OBi2O3ZrO2 nanocomposite is prepared by a sustainable, lower-cost, and simple hydrothermal-based phyto-synthesis route by using Amaranthus Viridis L. amaranthaceae plant (abbreviated as AVL.A). The synthesized AVL.A-Cu2OBi2O3ZrO2 nanocomposite is characterized by powder-X-ray diffraction and FE-Scanning electron microscopy for its phase composition and surface morphology. The electrochemical efficiency of AVL.A-Cu2OBi2O3ZrO2 nanocomposite is investigated for supercapacitors and overall water splitting. The fabricated Cu2OBi2O3ZrO2 nanocomposite-based Nickel foam (NF) electrode shows superior performance with a specific capacitance of 524.5 F/g at 2 mV/s and 400 F/g at 1 A/g. The excellent rate capability is observed at scan rates from 2 mv/s to 300 mV/s and at current densities from 0.5 A/g to 30 A/g for AVL.A-Cu2OBi2O3ZrO2–NF. Furthermore, fabricated AVL.A-Cu2OBi2O3ZrO2–NF shows excellent electrochemical stability with 100% Coulombic efficiency till 5000 charge-discharge cycles. As bifunctional electrocatalyst AVL.A-Cu2OBi2O3ZrO2–NF electrode exhibits 117 mV overpotential at 10 mA/cm2 current density for HER kinetics along with 112 mV/dec Tafel slope values. The same Tafel slope value is also observed for OER measurements. These values of overpotential and Tafel slope for AVL.A-Cu2OBi2O3ZrO2–NF suggest a rapid and efficient electrochemical process of AVL.A-Cu2OBi2O3ZrO2–NF bifunctional electrocatalyst for energy generation. Overall study highly proposed AVL.A-Cu2OBi2O3ZrO2–NF as the potential electrode for energy storage supercapacitor and energy generation overall water splitting.

Eco-Friendly Mycogenic Synthesis of Iron Oxide Nanoparticles Using Volvariella volvacea and Unveiling its Potential as Antibiofilm and Anticancer Agents

Abstract This research explores the eco-friendly creation of functional, biocompatible nanomaterials through green chemistry, utilizing natural extracts over chemicals to produce metal and metal oxide nanoparticles. The study focuses on iron oxide nanoparticles synthesized with Volvariella volvacea (GIONP) and evaluates their physical, chemical, and biological traits, including their anticancer capabilities, against traditionally made IONPs (CIONP). GIONPs, confirmed by UV-visible spectroscopy and dynamic light scattering, showed enhanced stability and consistent size distribution. They also demonstrated smaller sizes via Fe-scanning electron microscopy analysis, and X-ray diffraction and Fourier transform infrared studies verified their crystalline structure and organic functional groups. Notably, GIONPs exhibited strong antioxidant properties, low toxicity to blood cells, promising for intravenous use, and greater antimicrobial and antibiofilm activities against various bacterial strains than CIONPs. The study revealed that both GIONPs and CIONPs exhibit a similar degree of toxicity towards MDA-MB 231 cancer cells. The internalization of GIONPs within these cells was verified through a Prussian blue assay and further supported by the concentration-dependent increase in intracellular iron levels post-treatment. These findings underscore the successful formulation of GIONPs that are not only biocompatible and eco-friendly but also capped with bioactive compounds, highlighting their promising applications in the field of biomedicine.

The Structural Properties of Nano-Coppers Synthesized via the Electric Wire Explosion Method and Application as Anti- Escherichia coli Bacterial

In this research, copper nano powders Cu NPs were successfully prepared via laser triggering wire explosion technique at different explosion voltage (4, 5 and 7 KV). It was observed through X-ray diffraction examinations that the prepared powders have a polycrystalline structure and their characteristic peaks correspond to copper and copper oxide. FE-scanning electron microscopy images showed that the prepared powders had a nanostructure and regular morphology, and the regularity increased with increasing explosion voltage. Antibacterial activity tests showed the efficiency of the prepared powders in eliminating Escherichia coli bacteria, especially the powder prepared at 7KV voltage and at concentration 200 µg/mL.

Novel green synthesis of zinc oxide nanoparticles using Salvia rosmarinus extract for treatment of human lung cancer

Abstract A green and low-cost approach was run to synthesize zinc nanoparticles (NPs) using rosemary extract. The NPs were identified by various methods, i.e., ultraviolet-visible and Fourier transform infrared spectroscopy, FE-scanning electron microscope imaging, X-ray diffraction, and energy-dispersive X-ray analysis. The radical scavenging activity and MTT assays were used to evaluate the biological activity of ZnO-NPs@Rosemary. The results revealed a spherical shape for ZnO-NPs@Rosemary with a crystal size of 30.74 nm. ZnO-NPs@Rosemary could scavenge the free radicals of DPPH with an IC50 of 87.62 ± 0.47 μg/mL. An MTT assay was run to investigate the anti-cancer activity of ZnO-NPs@Rosemary against PC-14, LC-2/ad, and HLC-1 as the selected lung cancer cell lines. The highest sensitivity of NPs was found against PC-14 with IC50 of 178.84 ± 2.13. A dose-dependent activity was observed for ZnO-NPs@Rosemary against the chosen cell lines. The outcomes of the present study revealed an acceptable anti-lung cancer activity of ZnO-NPs@Rosemary.

Artificial intelligence optimization and experimental procedure for the effect of silicon dioxide particle size in silicon dioxide/deionized water nanofluid: Preparation, stability measurement and estimate the thermal conductivity of produced mixture

Recent studies for nanofluids, did not pay enough attention to the effect of the nanoparticle size and nanofluid stability on the heat transfer rate. In this study, the thermal conductivity (TC) coefficient of silica/deionized water (DW) nanofluid with various sizes of nanoparticles and various rates of nanofluid stability was investigated. Validation experiments, including X-Ray diffraction analysis (XRD), FE-Scanning Electron Microscopy (FE-SEM), Dynamic Light Scattering (DLS), and Zeta Potential (Zp), were carried out to examine the particle sizes and the nanofluid stability. The results illustrated that increasing the temperature leads to the augmentation of the TC coefficient of the SiO2/deionized water in all nanoparticle sizes and all volume concentrations. Also, increasing the volume concentration of the nanofluid leads to the augmentation of the TC coefficient of the nanofluid in all nanoparticle sizes and all temperatures. Eventually, increasing the nanoparticle sizes causes the TC coefficient of the nanofluid to be decreased in all volume concentrations. For the 11 nm nanoparticle size, the amount of the Relative TC (RTC) coefficient enhancement by increasing the temperature was 1.2%, 2.5%, 4.7%, and 6.8% for concentrations of 0.0.1%, 0.1%, 0.5%, and 1%, respectively. For the 50 nm nanoparticle size, this enhancement was from 0.7% to 6.5%, and for the 70 nm nanoparticle size, it was from 0.5% to 5.7%. Finally, Artificial Intelligence (AI) optimization was done to find the optimized size and stability.

Experimental and numerical investigation of the effect of graphene nanoparticles on the strength of sandwich structures under low-velocity impact

The effect of graphene nanoparticles on the strength of a sandwich panel structure based on foam core, which is inspired by the microstructure characteristics of dragonfly wings, has been investigated experimentally and numerically under low-velocity impact. Sandwich panel structures are made of E-glass/epoxy layers, and different percentages of graphene nanoparticles and combined with their resin. Also, polyurethane foam was used for its central core. For numerical modeling, a nonlinear progressive damage model of composite and nano-composite shells is incorporated into the finite element (FE) code by VUMAT subroutine. The numerical results were compared with the collected experimental data and it shows that there is a good compatibility between them. To check the damage in the structures, the images of the cut view of the samples were taken from the damaged area, and the results were reported. In order to evaluate the distribution of graphene nanoparticles in the polymer structure, the manufactured samples were analyzed using the FE-scanning electron microscopy analysis device. It was concluded that this type of sandwich structure inspired by dragonfly wings can limit damage propagation and keep the rest of the structure healthy under low-velocity impact.

Fabrication of fabric-like bacterial cellulose/activated carbon membrane for filtering layer applications of face masks by using textile padding method

PurposeBacterial cellulose (BC) is an ideal alternative filtering material. However, current functionalization approaches for BC have not been fully discovered industrially as well as academically applying textile processing. This study aims to create a sustainable fabric-like membrane made of BC/activated carbon (AC) for applications in filtration using textile padding method, to protect people from respiratory pandemics.Design/methodology/approachFabric-like BC is first mechanically dehydrated then AC is loaded via a textile padding step. The finishing efficacy, properties of fabric-like BC/AC and NaOH pretreatment are analyzed and characterized by scanning electron microscope (SEM), field emission scanning electron microscope (FE SEM), X-ray diffraction (XRD), CIELab color space, color strength (K/S), nitrogen adsorption-desorption isotherm including Brunauer–Emmett–Teller (BET) specific surface area and Barrett–Joyner–Halenda (BJH) pore size and volume.FindingsThis research results in a fabric-like BC/AC with pore diameters of 3.407 ± 0.310 nm, specific surface area of 115.28 m2/g and an efficient scalable padding process, which uses 8 times less amount of chemical and nearly 30 times shorter treating duration than conventional methods.Practical implicationsOur globe is now consuming an alarming amount of non-degradable disposable masks resulting in massive trash buildup as a future environmental problem. Besides, current disposable masks requiring a significant upfront technological investment have posed challenges in human protection from respiratory diseases, especially for countries with limited conditions. By combining a sustainable material (BC) with popular padding method of textile industry, the fabric-like BC/AC will offer sustainable and practical values for both humankind and nature.Originality/valueThis research has offered an effective padding process to functionalize BC, and a unique fabric-like BC/AC membrane for filtration applications.

Effect of Heat Treatment on Microstructure and Selective Corrosion of LPBF-AlSi10Mg by Means of SKPFM and Exo-Electron Emission.

The paper deals with the evolution of the microstructure of AlSi10Mg alloy obtained by laser powder bed fusion (LPBF), as a function of the post-processing heat treatment temperature. This was approached by complementary methods including FE-scanning electron microscopy, scanning Kelvin probe force microscopy and exo-electron emission techniques. The fast cooling rate of the LPBF process as compared to traditional casting produces a very fine microstructure with high mechanical properties and corrosion resistance. However, the LPBF-AlSi10Mg alloy can be susceptible to selective corrosion at the edge of the melt pools generated by the laser scan tracks. Post-process thermal treatments of the Al alloy induce a marked modification of the silicon network at melt pool edges, in particular at high temperature such as 400 °C. It was found that this is associated to a more homogeneous distribution of Volta potential. Analysis of exo-electron emission confirms the silicon diffusion during thermal treatment. The modification of the silicon network structure of the LPBF-AlSi10Mg during thermal treatment reduces the susceptibility to selective corrosion.

An effective polymer nanocomposite based on tetraethoxysilane (TEOS) and SiO2-Al2O3 nanoparticles for super protection of damaged ancient Egyptian wall paintings

PurposeThis contribution aims to introduce an effective low cost polymer-nanocomposite for possible application to achieve a super protection for highly damaged ancient Egyptian wall paintings.Design/methodology/approachSiO2 and Al2O3 nanoparticles were synthesized by the sol-gel method. Then, the polymer-nanocomposite was prepared by simple mixing and dispersing the nanoparticles into the tetraethoxysilane polymer solution, with the aid of an ultrasonic dismembrator. The application of the polymer-nanocomposite and other polymeric nanodispersions, on laboratory models, was performed by the brushing technique. Next, the materials stability was evaluated by means of digital optical microscope, colorimetry, FE-scanning electron microscope, measuring the static contact angle and water absorption rates.FindingsThe results were promising in creating a superhydrophobicity and the static contact angle (?S) measured for the polymer-nanocomposite reached 135o. An average of three measurements of the water absorption rate after polymer-nanocomposite treatment was 0.66 g/m2 s, compared to 2.60 g/m2 s for the control model (untreated). Further, an average of color difference (?E*) for the treated surface was 2.78, and after the accelerated thermal aging was 3.6. Observing the surface morphology, the polymer-nanocomposite enhanced the roughness of the treated surface and showed a high resistance to laboratory salt weathering.Practical implicationsPreparation of a polymer-nanocomposite by adding SiO2 and Al2O3 NPs to tetraethoxysilane polymer has been proposed. As a promising conservation material, the produced polymer-nanocomposite helped to form an efficient protective film.Originality/valueThis paper attains to develop an economic polymer-nanocomposite to maintain a high protection to damaged ancient Egyptian wall paintings and similar objects.

Effect of selected physical and chemical modifications on physicochemical, pasting, and morphological properties of underutilized starch from rice bean (Vigna umbellata).

Starch was extracted from the rice bean which is largely underutilized and modified by physical (i.e. heat moisture treatment and retrogradation) and chemical (i.e. esterification and acid alcohol modification) methods. Both, physical and chemical modifications significantly (p < 0.05) affected the physicochemical, pasting, particle size and morphological properties of rice bean starch. Both amylose content and swelling power reduced after physical and chemical modifications. Among modified starches, retrograded starch showed higher solubility (8.56%) at 90°C. Retrogradation also resulted in higher values of water (251%) and oil absorption (106%) capacities in comparison to other modified starches. Physical modifications greatly influenced the pasting properties in comparison to chemical modifications. The particle size distribution followed the order: native starch (659.8nm) > heat moisture treated (434.3nm) > retrograded (355.4nm) > esterified (218nm) > acid alcohol treated starch (234.5nm). The study revealed that the particle size of rice bean starch was reduced by both physical and chemical modifications. FE-Scanning electron microscopy was used to study the morphological characteristics of starches and it was observed that retrogradation had a pronounced effect on the starch granules morphology.

Electrospun Ti-doped haematite fibres and their properties

Electrospun Ti-doped α-Fe2O3 fibres were synthesized and their properties compared with electrospun α-Fe2O3 and TiO2 fibres as reference samples. All samples were characterized with FE SEM (field emission scanning electron microscopy), XRD (X-ray diffraction), 57Fe Mossbauer, FT-IR (Fourier transform infrared) and UV/Vis/NIR (ultraviolet/visible/near infrared) techniques. Ti-doped α-Fe2O3 fibres consisted of the interconnected nanoparticles. These fibres showed a hollow substructure. XRD and 57Fe Mӧssbauer spectroscopy showed the titanium cations to be incorporated up to 10 mol% into the α-Fe2O3 crystal structure. The incorporation of titanium cations into the α-Fe2O3 crystal structure caused changes in the corresponding FT-IR spectra. The band gap values of the electrospun fibres were determined and the photocatalytic degradation of rhodamine B (RhB) with the same fibres was investigated.

Adsorption and electrochemical regeneration of intercalated Ti3C2Tx MXene for the removal of ciprofloxacin from wastewater

Two-dimensional Ti 3 C 2 T x MXene nanosheets intercalated with sodium ions (SI-Ti 3 C 2 T x ) was synthesized by a facile batch fabrication method and applied for Ciprofloxacin (CPX) removal in the adsorption and electrochemical regeneration process. The successful synthesis and properties of the synthesized nanosheets were evaluated with X-ray diffraction (XRD), FE-scanning electron microscopy (SEM), FE-transmission electron spectroscopy, Zeta-potential analyses, and X-ray photoelectron spectroscopy. After intercalation, the surface terminations and the spacing between the layers of SI-Ti 3 C 2 T x MXene were increased which enhanced the adsorption capacity of nanosheets in terms of fast kinetics and higher removal rates. As a result, 10 mg L −1 CPX was reduced to approximately 1 mg L −1 in just 15–20 min, which is an extraordinary kinetic behavior in CPX adsorption. Elovich kinetic model and the Redlich-Peterson isotherm model fitted the experimental data with the highest correlation coefficient. SI-Ti 3 C 2 T x could be completely regenerated through an electrochemical regeneration approach within 5 min. Even after the subsequent adsorption and regeneration cycles, the removal rate enhanced up to ~99.7%. After the electrochemical treatment, the results of XRD and SEM indicated the stability of the material. Results obtained herein suggest that this type of nanoadsorbent will be useful in practical water treatment applications. • Sodium intercalated Ti 3 C 2 T x (SI-Ti 3 C 2 T x ) MXene nanosheets were fabricated using a simple batch reaction method. • The SI-Ti 3 C 2 T x MXene provided better CPX adsorption performance than pristine Ti 3 C 2 T x MXene. • An increase in spacing between layers and higher surface terminations collectively enhanced the adsorption capacity. • The electrochemical technique along with complete regeneration improved the adsorption capacity. • SI-Ti 3 C 2 T x was found to be stable for five regeneration cycles.

Application of SEM Observation on Coating Layer for Latex Binder Improvement

Observation of a coating layers is one of the most eff ective ways to improve latex binder for paper coating. For many years, we have studied coating layers and their latex binder with many analysis methods such as electron probe micro analysis, quantitative analysis of starch and scanning electron microscopy （SEM）. Field emission scanning electron microscopy （FE–SEM） provides us with sharp images at high magnifi cation （Fig. 2）. By using FE–SEM, we clarifi ed a relationship between a coating layer and latex binder properties. In this paper, we show following three results of our works：1. an eff ect of diff erent drying conditions of coating layer on latex distribution in coating layers, 2. a relationship between latex particle size and dry pick strength of coating layers, 3. observation of coating layer with the new generation High–Performance latex.

Antimicrobial action of methanolic seed extracts of Syzygium cumini Linn. on Bacillus subtilis

Phytochemicals of Syzygium cumini are used for the treatment of various diseases as a traditional medicine but the mechanism behind their action is not well reported. Antimicrobial activity of methanolic seed extract of S. cumini was done by agar well diffusion assay on Bacillus subtilis and its zone of inhibition was found to be 20.06 mm in comparison to control having no zone of inhibition. MIC of S. cumini was found to be 0.3 mg/ml. Genomic DNA degradation of B. subtilis reveals apoptosis and FE-scanning electron microscope indicates cell wall cracking on several intervals of time. Results of propidium iodide staining showed few bacterial cells were stained in control; however population of stained cells increased after exposing them for varying period of time. Flow cytometric kinetic data analysis on the membrane permeabilization in bacterial cell showed the significant contribution of antimicrobial potential of the seed extract on antimicrobial-induced permeabilization. In silico analysis revealed two components of S. cumini methanolic extract to be active against four enzymes (PDB ID—1W5D, 4OX3, 3MFD and 5E2F) which are crucial for plasma membrane synthesis in B. subtilis. Moreover lupeol showed highest binding energy for macromolecule 1W5D and 4OX3 forming one hydrogen bond each whereas stigmasterol showed the highest binding energy for macromolecule 3MFD and 5E2F forming four hydrogen bonds and alkyl bonds respectively. It demonstrates that methanolic seed extracts of S. cumini could be used for inhibition of food born infection caused by B. subtilis and also an alternative of prevalent antibiotics.

Effect of annealing temperature on properties of molybdenum disulfide thin films

The technologically significant molybdenum disulfide thin films were coated onto a non-conducting glass substrates using Automatic-CBD process. Consequences of annealed process on its physical appearance of the thin films, thickness, morphology, growth, structural and optical properties of the films were studied. The annealed sample shows an impact on the structural analysis, lattice cell, volume, average crystallite parameters. The effects of annealed temperature on the XRD pattern show that the increase of crystallite size leads to decrease in the grain boundary which will decrease in the dislocation density. Optical parameters measurement revealed that the optical band energies values of the annealed thin films lie in the range among 1.78–2.08 eV for temperature range 373–473 K. The obtained values were confirmed by photoluminesce. Surface morphology study by FE-scanning electron microscopy showed increase of grain sizes with annealing temperature. The Effect of annealed temperature on properties of thin films is discussed from the point of applications based on achieving high-performance opto-electronics and solar devices.

A novel one-step electrochemical preparation of silver nanoparticles/poly(3-methylthiophene) nanocomposite for detection of galantamine in human cerebrospinal fluid and narcissus

In this research, the manufacturing of highly sensitive and effective electrochemical sensor is presented. It is based on silver nanoparticles/poly(3-methylthiophene) (Ag–NPs/P3MT) nanocomposite for the detection of galantamine hydrobromide (Gal). In this process, Ag–NPs/P3MT modified electrode was fabricated by electro-polymerization of 3-methylthiophene (3MT) in the presence of silver nitrate on the surface of the glassy carbon electrode (GCE). Scanning electron microscopy (SEM), field emission scanning electron microscopy (FE–SEM) and energy dispersive X–ray (EDX) analysis were employed to characterize the constructed sensor. Compared with unmodified and P3MT modified electrodes, the Ag–NPs/P3MT modified electrode demonstrated superb electrochemical catalytic activity and significantly enhanced the oxidation peak current of Gal. The experimental parameters, such as supporting electrolyte and its pH, the number of cycles for the electro-polymerization and the scan rate for the sensor preparation were optimized. Under the optimal conditions, the proposed electrode exhibited excellent sensing performance for detecting of Gal using differential pulse voltammetry over the concentration range of 1.0 to 700μM and a detection limit of 0.18μM. Finally, the excellent results showed that the modified electrode can be successfully applied to quantitatively measure of Gal in human cerebrospinal fluid (CSF), Narcissus and pharmaceutical real samples with satisfactory consequences.

Determination of degradation kinetics of polyvinyl alcohol/X-zeolite nanocomposite

Poly(vinyl alcohol) (PVA) containing Ag-modified X-zeolite (PVA/X-zeolite) nanocomposite was successfully fabricated using solution casting technique. Morphology, structural and thermal properties of the pure PVA and its nanocomposite were characterized by FE-scanning electron microscopy (FE-SEM), energy-dispersive X-ray (EDX), X-ray diffraction, and differential scanning calorimetry (DSC), respectively. Results from DSC traces showed that the X-zeolite acts as efficient nucleating agent toward PVA crystallization. Photographs of FE-SEM demonstrate the nanosize and homogenous dispersion of the X-zeolite in PVA matrix. Moreover, EDX analysis confirmed the presence of constituent elements of the X-zeolite in the nanocomposite as well. Thermal degradation of PVA and PVA/X-zeolite nanocomposite was addressed in details by thermogravimetry analysis under non-isothermal conditions. Similar to pure PVA, the PVA/X-zeolite nanocomposite thermally degraded in two steps ranged from 400 to 690 K and 700 to 780 K, respectively. Values of the apparent activation energies were estimated using Friedman’s isoconversional method. A strong dependence of the Ea on conversion (α) was observed. To confirm the anticipated reaction models, differential master plot analysis was applied to the experimental data. Results showed that the degradation of PVA and its nanocomposite could be described by the reaction-order (A type) kinetic model.

Evolution of the Spectral Emissivity and Phase Transformations of the Al-Si Coating on Usibor® 1500P Steel During Austenitization

Usibor® 1500P coupons are austenitized in a Gleeble 3500 thermomechanical simulator using a two-step heating procedure in an argon atmosphere. Variations in spectral emissivity are measured in-situ using a near infrared spectrometer and ex situ with a Fourier transform infrared reflectometer. Microstructural evolution and surface roughness are investigated using optical microscopy, FE-scanning electron microscopy, and a surface profilometer. A series of phase transformations of Al-Fe-Si intermetallic phases at the coating/steel substrate interface cause the surface phase and surface roughness to change, which in turn influences the spectral emissivity. At the beginning of the first heating step, the coupons have very low spectral emissivity, due to the molten Al-Si coating. Spectral emissivity increases significantly with increasing soak time from 5 to 12 minutes, associated with the surface phase transformation of the coating into Al7Fe2Si intermetallic phase and an increase in surface roughness. Through the second step heating at 1173 K (900 °C), the spectral emissivity shows a gradually decreasing trend with increasing soak time, caused by the surface phase transformation from Al5Fe2 into AlFe intermetallic phase with a decrease in surface roughness.

Effect of initial water content and calcination temperature on photocatalytic properties of TiO2 nanopowders synthesized by the sol–gel process

The effects of initial water content and calcination temperature on sol–gel synthesized TiO2 powders were studied. Mother solutions had water/Ti-precursor mole ratios (R ratio) of 1, 5, 10, and 50. Dried aerogels were calcined for 3h at temperatures of 300, 400, and 500°C to obtain crystallized TiO2 nanopowders in the range of 15–30nm. FE-scanning electron microscopy and X-ray diffraction techniques were employed to investigate the morphological and structural properties of the nanopowders synthesized. Profound effect of gel viscosity was observed on the formation mechanism and extent of crystallinity in the powders. Methylene blue degradation test results suggest, photocatalytic performance is enhanced as initial water content and calcination temperature increased. Band-gap energy of the powders ranged from 3.09 to 3.27eV. Overall, this study shows that initial water content and calcination regime have a profound effect on the phase assembly, crystallite size, band-gap energy, and photocatalytic performance of sol–gel synthesized TiO2 nanopowders.

Rapid and facile synthesis of Mn doped porous LiFePO4/C from iron carbonyl complex

Porous Mn-doped LiFePO4/C cathode material was synthesized by facile and fast microwave assisted solid state reaction from iron carbonyl complex using citric acid as reducing agent and source of carbon. The microstructure and electrochemical performance were systematically investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), field emission scanning electron microscope (FE–SEM), transmission electron microscope (TEM), Raman spectroscopy, charge–discharge cycling, cyclic voltammogram and electrochemical impedance spectroscopy. It was found that the as-prepared composites have a single phase of orthorhombic olivine-type structure and Mn2+ has successfully introduced into the M2(Fe) sites. The electrochemical properties of LiFe0.99Mn0.01PO4/C were compared with bare LiFePO4 and LiFePO4/C composite prepared by identical route. Compare to as-prepared LiFePO4/C composites, LiFe0.99Mn0.01PO4/C demonstrates a remarkable electrochemical property in terms of discharge capacity, electrochemical reversibility and cycling performance with an initial discharge capacity of 163.2 mAh g−1 at a discharge rate of 0.1 C. It also performed excellent even at higher current densities. The improved electrochemical performance was attributed to the smaller particle size, porosity, the enhancement of the P–O bond and the facilitation of Li+ ion “effective” diffusion, induced by Mn2+-substitution.