X-ray Diffraction Results Research Articles

Low temperature growth of single-phase and preferentially oriented ɛ-Ga2O3 films on sapphire substrates via atomic layer deposition

As an ultrawide-bandgap semiconductor, Ga2O3 has promising applications in electronics and optoelectronics. ɛ-Ga2O3 has attracted much attention as it performs the polarization effect, whereas single-phase and preferentially oriented ɛ-Ga2O3 films have not been prepared by the atomic layer deposition (ALD) method at low temperatures. In this paper, Ga2O3 films are prepared on sapphire substrates through the ALD method at different substrate temperatures and using different O sources. The x-ray reflectivity measured thicknesses and x-ray photoelectron spectroscopy spectra both demonstrate that the Ga source of triethylgallium cannot reacts continuously with the O source of H2O layer-by-layer. The growth rates of Ga2O3 films using O3 or PE-O2 as the O source range from 0.342 to 0.448 Å/cycle. X-ray diffraction (XRD) results indicate that the as-grown Ga2O3 films at 250 °C are amorphous, no matter using O3 or PE-O2 as the O source. They both crystallize into the single-phase and (−201) preferentially oriented β-Ga2O3 films after a high-temperature annealing of 900 °C. When the growth temperature rises to 350 °C, single-phase and (0002) preferentially oriented ɛ-Ga2O3 films occur if using PE-O2 as the O source. The full width at half maximum for the (0004) plane of ɛ-Ga2O3 from the XRD rocking curve is 0.937° while the atomic force microscopy measured surface roughness RMS is 1.24 nm. The crystal structure of the as-grown ɛ-Ga2O3 films can be maintained at an annealing temperature of 700 °C and they transform into polycrystalline β-Ga2O3 films at 900 °C. The results are beneficial for the applications of Ga2O3-based microelectronic devices.

Investigation of deposition times on nano structures ferrous thin layers produced by chemical bath deposition method

Abstract Ferrous thin layers were deposited on SiO2 substrates by chemical bath deposition method, from aqueous solutions containing Ironchloride and sodium thiosulfateat 30, 60 and 120 minutes as deposition time. The effect of deposition time on the structural and optical properties of ferrous thin layers was investigated by X-ray diffraction (XRD), Atomic force microscopy (AFM) and SEM. According to XRD results, crystallinity of the layers with cubic pyrite phase increases with increasing the deposition time. AFM image showed the film’s surface is well covered with irregular grains. Morphology, roughness and grain structures were changed completely by increasing deposition times. Nanoparticles were clearly visible on the surface of the films. The optical properties were determined using UV-Vis Spectrophotometer. The optical band gap of the ferrous layers was between 3.20-3.35 eV at different deposition times.

Utilization of marine snails for the sustainable synthesis and crystallographic characterization of nano-crystallite hydroxyapatite

In the present investigation, several biogenic sources of calcium were used to produce HAp nanomaterials by the use of a typical wet chemical precipitation technique. To determine the development of HAp nanocrystals, a variety of characterization methods were used, including X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared (FT-IR) spectroscopy. The results of XRD were used to evaluate a wide range of factors related to structure, such as lattice parameters, degree of crystallinity, dislocation density, microstrain, crystallinity index, and preference growth. The crystallite size of the produced HAp crystals was calculated using the equations of different models. Each of the formed HAp exhibits crystal arrangements that are within the allowed range of 1–150 nm, which the aforementioned models were used to figure out from the XRD information. Furthermore, the EDX examination (Ca, P, and O percentages) and Rietveld refinement (about 95% HAp) verified the makeup of the resultant HAp particles.

Development of Polyvinyl Alcohol/Polyethylene Glycol Copolymer-based Orodispersible Films Loaded with Entecavir: Formulation and In vitro Characterization.

The aim of the study is to prepare entecavir (ETV)-loaded orodispersible films (ODFs) using polyvinyl alcohol (PVA)/polyethylene glycol (PEG) graft copolymer (Kollicoat® IR) as a film-forming agent, and further to evaluate the dissolution rate, mechanical and physicochemical properties of films. ETV-ODFs were prepared by a solvent casting method. The amount of film-forming agent, plasticizer, and disintegrating agent was optimized in terms of the appearance, thickness, disintegration time and mechanical properties of ODFs. The compatibility between the drug and each excipient was conducted under high temperature (60 °C), high humidity (RH 92.5%), and strong light (4500 Lx) for 10 days. The dissolution study of optimal ODFs compared with the original commercial tablet (Baraclude®) was performed using a paddle method in pH 1.0, pH 4.5, pH 6.8, and pH 7.4 media at 37 °C. The morphology of ODFs was observed via scanning electron microscopy (SEM). The mechanical properties such as tensile strength (TS), elastic modulus (EM), and percentage elongation (E%) of ODFs were evaluated using the universal testing machine. The physicochemical properties of ODFs were investigated using X-ray diffraction (XRD), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FT-IR). The related substances were less than 0.5% under high temperature, high humidity, and strong light for 10 days when ETV was mixed with excipients. The optimal formulation of ODFs was set as the quality ratio of Kollicoat® IR, glycerol, sodium alginate (ALG-Na): TiO2: MCC+CMC-Na: ETV was 60:9:12:1:1:1. The drug-loaded ODFs were white and translucent with excellent stripping property. The thickness, disintegration time, EM, TS, and E% were 103.33±7.02 μm, 25.31±1.95 s, 25.34±8.69 Mpa, 2.14±0.26 Mpa, and 65.45±19.41 %, respectively. The cumulative drug release from ODFs was more than 90% in four different media at 10 min. The SEM showed that the drug was highly dispersible in ODFs, and the XRD, DSC, and FT-IR results showed that there occurred some interactions between the drug and excipients. In conclusion, the developed ETV-loaded ODFs showed relatively short disintegration time, rapid drug dissolution, and excellent mechanical properties. This might be an alternative to conventional ETV Tablets for the treatment of chronic hepatitis B.

Characteristics of cast Ti53.3-xNb10Zr10Ni10Co10Fe6.7Bx compositionally complex alloys

In the current investigation, elemental boron was added to form a series of Ti53.3-xNb10Zr10Ni10Co10Fe6.7Bx Compositionally Complex Alloys (CCAs). Alloying was done via vacuum arc melting in amounts of 0.0, 5.3, and 10.6 at.%. From the thermodynamic parameters, adding B to the base alloy increased the system’s entropy. The microstructure of the prepared CCAs was characterized using scanning electron microscopy, transmission electron microscopy, and X-ray diffraction (XRD). The mechanical properties of CCAs as related to microstructure were assessed. According to XRD results, B-based intermetallic phases were obtained in the prepared CCAs, which were binary as Ti3B4 and ZrB2 and ternary as FeNbB and Nb3Co4B7. These intermetallic phases notably provided strengthening effects to the B-added alloys. Ti48Nb10Zr10Ni10Co10Fe6.7B5.3 CCA showed the most homogenous microstructure obtained by the arc melting process. Adding B increased Young’s modulus from 141 GPa (without B) to 195 GPa and 260 GPa with 5.3 and 10.6 at.%B, respectively. Hardness also increased from 502 to 606 HV with 5.3 at.% B and to 648 HV with 10.6 at.%B. Accordingly, the wear resistance increased with B addition where 10.6 at.%B sample showed the lowest wear rate among the other conditions. However, 5.3 at.% B was nominated as the optimum addition amount due to its notable microstructure homogeneity.

The effect of annealing on the structural, optical, electrical and photoelectric properties of ZnO/NiO heterostructures

In this study, n-ZnO/p-NiO heterostructures on glass substrates with an indium tin oxide (ITO) covering were obtained by using the spray pyrolysis methodology. In order to act on the structural and local compositional defects, the samples were annealed under vacuum in the temperature range of Ta = (300 – 500)°C in steps of ΔT = 50°C. X-ray diffraction results indicate the presence of only the hexagonal ZnO and cubic NiO phases in the studied samples, which was confirmed by Raman spectroscopy. Low-temperature photoluminescence (PL), as well as absorption and photoconductivity, were studied to establish the optical properties, the nature of electronic optical transitions, the energy level position of the different defects present in the samples, and the effect of temperature annealing on these properties The band gap of the compounds was determined using the Tauc approximation and the first derivative of the absorption coefficient. Likewise, the current-voltage characteristics of the n-ZnO/p-NiO heterostructures and their diode character, were analyzed.

Chemical composition, rheological properties and calcium-induced gelation mechanism of Premna microphylla Turcz polysaccharide

The aim of this study was to investigate the chemical composition, molecular weight (Mw), and monosaccharide composition of Premna microphylla Turcz polysaccharide (PMP) and revealed the effects of calcium ions (Ca2+) on the rheological properties, thermal stability, texture properties, and structural properties of PMP gels. Additionally, the gelation mechanism of PMP was proposed. The results revealed that PMP was a negative charge acidic polysaccharide primarily composed of glucose, galactose and rhamnose. The results of small and large amplitude oscillatory shear experiments illustrated that the storage modulus (G′), loss modulus (G″), relaxation modulus (G(t)) of PMP gels showed a positive correlation with Ca2+ concentration, indicating the addition of Ca2+ improved the viscoelasticity and shear thinning capacity of PMP gels. Furthermore, the gel strength, hardness, and thermal stability of PMP gels were enhanced with increase of Ca2+ concentration. The microstructure of PMP gel was changed obviously after adding Ca2+, generating the lamellar and lump-like structure due to the PMP aggregation. The results of Zeta potential, X-ray diffraction, and Fourier transform infrared spectroscopy (FT-IR) analysis indicated that electrostatic interactions played a crucial role in the formation of PMP gel and three-dimensional structure. These results suggested that PMP had great potential for application in the food industry due to their excellent gelation properties.

Comparative analysis of thermally evaporated nanoscale CdS thin film's structural, morphological, optical and nanomechanical properties

CdS nanoscale thin films were deposited on glass substrates at 1, 5 and 10 Å/s deposition rates by thermal evaporation process. The structural, morphological, compositional, optical and nanomechanical properties of CdS thin films were analyzed by X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), energy dispersive x-ray (EDX), UV-vis spectrophotometer and nanoindentation. XRD diffractogram indicate that the deposited CdS thin films have hexagonal structure with preferred orientation towards (002) plane and nearly stoichiometric composition. Various crystal structure parameters like lattice constant, crystallite size, defect density, dislocation density, lattice strain, number of crystallite per unit surface, stacking fault were determined. From XRD results, the calculated crystal structure parameters such as the crystallite size, microstrain and defect density were in the range of 20.4-14.7 nm, 7.74-10.62 and 2.3-4.52 × 1011 lines/cm2, at 1, 5 and 10 Å/s deposition rates, respectively .The AFM images indicated that the film's rms surface roughnesses were 2.73 nm, 2.94 nm and 3.18 nm at 1, 5 and 10 Å/s, respectively. The SEM images indicated that the films were uniform, continuous and defect free. The EDX examination revealed that at 1 Å/s deposition rate the film was nearly stoichiometic. The optical band gaps were determined to be in the range of 2.37-2.43 eV. Nanoindentation tests evaluated the hardness, Young's modulus, creep behavior and strain rate of CdS films. Hardness evaluated to be 0.14-1.48 GPa, 0.15-2.46 GPa, and 0.21-2.55 GPa at 1,5 and 10 Å/s deposition rate, respectively for 20-50 µN load. The Young's modulus decreases 1-5 Å/s deposition rate and becomes almost constant 5-10 Å/s deposition rate at 70 µN load. The characterization of CdS thin film recommend it as a favorable window layer in applications like photovoltaic, optoelectronic, thermoelectric and solar cells.

Eco-friendly fabrication of copper oxide nanoparticles using peel extract of Citrus aurantium for the efficient degradation of methylene blue dye

This study presents a simple, sustainable, eco-friendly approach for synthesizing copper oxide (CuO) nanoparticles using Citrus aurantium peel extract as a natural reducing and stabilizing agent. The synthesized CuO and CuO-OP were characterized using various techniques, including surface area measurement (SBET), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDX), and high resolution transmission electron microscope (HRTEM). DRS analysis determines band gap energy (Eg) of 1.7 eV for CuO and 1.6 eV for CuO-OP. FTIR confirmed the presence of Cu–O bond groups. The XRD and HRTEM results revealed monoclinic and spherical nanostructures, with average particle sizes ranging from 53.25 to 68.02 nm, as determined via Scherer’s equation. EDX analysis indicated incorporation of carbon (1.6%) and nitrogen (0.3%) from the peel extract. The synthesized CuO and CuO-OP NPs exhibited excellent photocatalytic efficiencies for methylene blue dye under UV irradiation, reaching 95.34 and 97.5%, respectively, under optimal conditions; the initial dye concentration was 100 mg/L, the pH was 10, the catalyst dosage was 1 g/L, and the contact time was 120 min. Isothermal studies showed that the adsorption of MB onto the nanoparticles followed the Freundlich isotherm model (R2 = 0.97 and 0.96). Kinetic studies indicated that the degradation followed pseudo-first-order kinetics, with rate constants (K1) of 0.0255 min−1 for CuO and 0.033 min−1 for CuO-OP. The sorption capacities were calculated as 98.19 mg/g for CuO and 123.1 mg/g for CuO-OP. The energy values obtained from the Dubinin–Radushkevich isotherm were 707.11 and 912.87 KJ mol−1, suggesting that chemisorption was the dominant mechanism.

Analysis of minerals and phytochemicals in the leaves of the Ocimum kilimandscharicum plant using spectroscopic methods and screening of antibacterial activity

This study presents an innovative X-ray diffraction (XRD) application to identify minerals in the medicinal plant Ocimum kilimandscharicum. Additionally, this study includes the analysis of chemical compounds and screening antibacterial activity in the leaf extract, using Gas Chromatography-Mass Spectrometry (GC-MS) and UV-visible spectroscopy. The results of X-ray diffraction showed that the leaves are a rich source of minerals such as oxides of Potassium, Magnesium, and Calcium. The GC-MS analysis revealed that the leaf extract of Ocimum kilimandscharicum possesses Eugenol (27.53%), Camphor (16.91%), Thujopsene (13.53%) as major components and UV-visible studies showed the existence of Phytochemicals such as chromophores, carotenoids, and chlorophyll. The ethanol extract of leaves showed antimicrobial activity against four microorganisms. It significantly inhibited Bacillus subtilis , E.Coli, and Staphylococcus aureus, surpassing the positive control streptomycin. These findings suggest the potential of using leaves of Ocimum kilimandscharicum for curing infectious diseases and can be used as a mineral supplement.

Green Synthesis of Iron Oxide from Lathe Waste Using Green Tea Leaves (<i>C</i><i>amellia</i><i> s</i><i>inensis</i>) Extract by Temperature Variations of Synthesis

Iron oxide was produced from lathe waste using green tea leaf extracts. Green tea leaves contain catechins, has been produced as a possible reducing, precipitating, stabilizing, and capping agent. Another advantage of applying green tea leaves to synthesize iron oxide is reducing toxicity. Various temperatures of synthesis utilizing the precipitation method proved successful in the formation of hematite. X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscope (SEM) were used to characterize the synthesis product. According to the XRD results, the magnetite transition phase was obtained after precipitation, while hematite formed after calcination. The crystallite sizes were 50.5 nm, 45.4 nm, and 39 nm, respectively. According to FTIR identification, the iron oxide was generated before and after calcination in the presence of a specific Fe-O group at the wavenumbers 553 cm-1 and 451 cm-1. The SEM results revealed that the particle size ranges from 4.61 nm – 20.74 nm, and the shape was not uniform, and aggregation.

Molecular beam epitaxy and band structures of type-II antiferromagnetic semiconductor EuTe thin films

The rare-earth Eu-based compounds with a unique half-filled 4f orbital have attracted an amount of research interest recently. Here, we synthesized EuTe(001) single-crystal thin films on SrTiO3(001) substrate via molecular beam epitaxy (MBE). The scanning tunneling microscopy and x-ray diffraction results indicate that the grown EuTe thin films orientated as EuTe[100]//SrTiO3[110] in plane. In the angle-resolved photoemission spectroscopic (ARPES) measurements, the grown EuTe films show a semiconductive band structure with the valence band maximum lying on the center point of the Brillouin zone. The bandgap size of EuTe was further identified by the optical transmission spectra as 2.2 eV. The antiferromagnetic transition temperature of the grown EuTe film is 10.5 K measured by a superconductive quantum interference device (SQUID). Our results provide important information on the fundamental electronic structures for the further research and applications of the Eu-based compounds.

Improving the thermochromic performance of VO2 films by embedding Cu-Al nanoparticles as heterogeneous nucleation cores in the VO2/VO2 bilayer structure

VO2-based films show great potential applications in thermochromic smart windows. However, enhancing luminous transmittance (Tlum) while maintaining high solar modulation ability (ΔTsol) remains a formidable challenge. Here, we present a novel VO2/Cu-Al nanoparticles (NPs)/VO2 composite film structure, seamlessly integrating Cu-Al bimetallic NPs within VO2 films by pulsed laser deposition on alkali-free glass substrates. The content of Cu-Al NPs in the composite films is controlled by the pulse number (Np) applied to the Cu-Al alloy target. X-ray diffraction results indicate that the crystallinity of VO2 films is significantly enhanced by the incorporation of an appropriate amount of Cu-Al NPs. The SEM characterization results revealed that the particle size of VO2 composite films initially increases to approximately 131 nm and subsequently decreases to around 120 nm as Np increases, with a concurrent transition in particle shape from quasi-circular to elongated. The Tlum and ΔTsol of the resulting composite films were dramatically improved to 71.6 % and 9.5 %, respectively, when Np was 300. These enhanced thermochromic properties are attributed to the localized surface plasmon resonance (LSPR) of the VO2 particles. This research opens up a promising avenue for the convenient production of customized high-quality VO2 films tailored for smart window applications.

Fabrication of graphene oxide-reinforced polyvinyl alcohol and study effect of thermal annealing of GO/PVA nanocomposites on their properties

In the presented work, graphene oxide (GO) was obtained as a plate using the Hummer technique. X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) show the formation of pristine GO. Composite materials were prepared by adding different percentages of GO to polyvinyl alcohol (PVA) (2%GO/PVA, 3% GO/PVA, and 20% GO/PVA). To determine the effect of thermal annealing on the structure, physical properties, and morphology of the samples, thermal annealing of the samples was performed for 1 hour at temperatures (40°C, 70°C, and 110°C). Following that, to explore how the characteristics of GO/PVA composites vary with concentration and thermal annealing temperature, the structural, optical, and morphological features of the samples were determined using XRD, Fourier-transform infrared (FTIR), and Raman spectroscopy, as well as SEM used to investigate the properties of all samples. From the XRD results, by the increasing thermal annealing temperature, the space between the sheets is decreased. From Raman measurements, the ID/IG ratio for 2% and 3% GO/PVA composite materials increased with increasing temperature compared to the pristine GO. It indicates that the defect in the structure increases due to the effect of temperature.

Quantitative characterization of crystallinity in semi-crystalline fluoropolymer through 19F LF-NMR relaxometry

Crystallinity is important to the properties of a semi-crystalline fluoropolymer, such as solubility, mechanical property, bonding strength, etc. This study extended the use of 19F Low-Field Nuclear Magnetic Resonance (19F LF-NMR) to the measurement of crystallinity in the semi-crystalline fluoropolymer F2314, which is the copolymer of vinylidene fluoride (VDF) and chlorotrifluoroethylene (CTFE) with a molar ratio of 1:4 and commonly used as binder in polymer-bonded explosives (PBXs). Based on the difference between spin-spin relaxometry of the 19F in crystalline region and in amorphous region, the crystallinity of F2314 can be qualitatively characterized. The obtained crystallinity exhibited a positive correlation to the time duration of thermal treatment, which is in consistent to the result of Differential Scanning Calorimetry (DSC) and X-Ray Diffraction (XRD). Moreover, 19F LF-NMR detected the slight decrease in segmental motion of crystalline region with the increase of crystallinity, and on-line monitored the evolution of segmental motion during heating. This study not only demonstrates the practicality and reliability of 19F LF-NMR in quantification of crystallinity, but also laid the foundation for in-situ characterization of fluoropolymers in PBXs in future work.

Effect of carbon coating on the structure and electrochemical properties of β-LiVOPO4 cathode material for lithium-ion batteries

β-LiVOPO4 has the advantages of high energy density, high voltage platform and low cost. It is a promising cathode material for lithium ion batteries. However, its poor magnification hinders the further development of the material. Here, aiming at the problem of poor rate performance of β-LiVOPO4, we successfully prepared β-LiVOPO4@C material by high temperature solid phase method using glucose as carbon source. The X-ray diffraction (XRD) results indicate that a small amount of α-LiVOPO4 produced during the initial calcination may transform into β-LiVOPO4 after the secondary heat treatment with the carbon source. Scanning electron microscopy (SEM) and pore size distribution results show that carbon coating makes the size of β-LiVOPO4 particles smaller, which is more conducive to the transport of Li+. Raman spectroscopy analysis showed that the β-LiVOPO4@4%C material contained more p3 hybrid graphite carbon, which enhanced the electronic conductivity. The results of X-ray photoelectron spectroscopy (XPS) analysis showed that the content of V5+ in β-LiVOPO4@4%C increased after charging to 4.5 V, which confirmed that the charge-discharge reaction was more thorough and could provide more discharge specific capacity. In addition, the π plasmon peak of β-LiVOPO4@4%C becomes stronger, which improves its electron transport rate. The electrochemical test results show that the Li+ diffusion rate of β-LiVOPO4 material coated with 4 % carbon is significantly improved, and it has good rate performance. It delivers a discharge capacity of 140.5 mAh g−1 at 0.1C and a discharge specific capacity of 80.5 mAh g−1 at 0.5C, indicating that it is expected to be used as a cathode material for advanced lithium-ion batteries.

Microbial biosurfactant-mediated green synthesis of zinc oxide nanoparticles (ZnO NPs) and exploring their role in enhancing chickpea and rice seed germination

Malnutrition is one of the greatest challenges faced by humanity, which may be addressed by improving crop productivity to ensure food security. However, extensive use of synthetic fertilizers can lead to soil fertility degradation. This study highlights the potential of combining nanotechnology with biotechnology to enhance the germination rates of commercially important crop seeds. Bacterial biosurfactant extracted from a newly isolated Klebsiella sp. strain RGUDBI03 was used as a reducing and capping agent for the synthesis of zinc oxide nanoparticles (ZnO NPs) through a simple method. Extensive characterization of ZnO NPs through electron microscopic analysis showed well-dispersed, homogeneous NPs with a size range of 2–10 nm. High-resolution transmission electron microscopy (HR-TEM) images also revealed molecular fringes of 0.26 nm in single crystal ZnO NPs, with approximately 50% of the NPs exhibiting a size range of 2–4 nm. X-ray diffraction (XRD) results of ZnO NPs indicated the presence of (100), (002), (101), (102), (200), and (112) planes, confirming their crystalline nature. The presence of C = C–H, C = C, C–H, and C = C groups in both the bacterial biosurfactant and ZnO NPs, as depicted by Fourier-transform infrared spectroscopy (FTIR) spectra, confirmed the function of the biosurfactant as a reducing and capping agent. The nano-primed chickpea (Cicer arietinum) and rice (Oryza sativa) seeds showed an increase in water uptake rate, 89% and 92% respectively, compared to the control (73% and 44%), leading to an enhanced germination rate of 98% and 76%, compared to their respective controls (80% and 30%) under optimized conditions. Additionally, the nano-primed seeds exhibited higher levels of α-amylase activity in both seeds (0.37 mg/g for chickpea and 2.49 mg/g for rice) compared to the control. Notably, the ZnO NP priming solution exhibited no cytotoxicity on red blood cells and earthworms (Eudrilus eugeniae), indicating their non-cytotoxic and eco-friendly nature for future field trials.

Effect of carbon coating on improved electrical and electrochemical performance of Li3Co2SbO6

Abstract We reported a novel high voltage cathode having layered structure and manifold improvement (144%) in electrochemical performance on carbon coating Li3Co2SbO6. The carbon-coated Li3Co2SbO6 has been prepared using a high temperature solid-state method in an air medium with appropriate stoichiometry of the oxide and carbon source (sucrose). The x-ray diffraction and high-resolution transmission electron microscopy results have confirmed homogeneous carbon coating on oxide (Li3Co2SbO6) surface without disturbing phase, structure and morphology. The immediate effect of carbon coating resulted in electrical conductivity enhancement of the carbon coated Li3Co2SbO6 by four order of magnitudes ∼2.79 × 10−4 Scm−1 at room temperature vis-a-vis pristine Li3Co2SbO6. The electrochemical performance of the carbon coated Li3Co2SbO6 has shown sustainable improvement indicating redox activity by more than one Li+ transaction. The carbon coated Li3Co2SbO6 cathode exhibited an initial discharge capacity of 110 mAhg−1 compared to 45 mAhg−1 for its pristine counterpart. The improvement in electrochemical capacity on carbon coating, as reported in this work, is the highest ever compared to prior literature reports on Li3Co2SbO6.

Synthesis, characterization, magnetic and morphological properties of poly(m-phenylenediamine)/ZnCoFe2O4 nanocomposites

In this work, poly(m-phenylenediamine) (PmPD)/ZnCoFe2O4 nanocomposites (NCs) were synthesised by in-situ chemical oxidative polymerisation method. The ZnCoFe2O4 nanoparticles (NPs) were prepared by auto-combustion method. The crystalline size of PmPD/ZnCoFe2O4 NCs and ZnCoFe2O4 NPs were calculated using the Powder X-ray diffraction (XRD) analysis. The functional group of the samples was analysed by Fourier transform infrared spectral (FTIR) analysis. The XRD and FTIR results were clearly indicated that the formation of PmPD/ZnCoFe2O4 NCs. The spherical morphology of the PmPD/ZnCoFe2O4 NCs was confirmed through Field emission electron microscopy (FESEM). The magnetic hysteresis (M-H) loops of ZnCoFe2O4 NPs and PmPD/ZnCoFe2O4 NCs were revealed their ferromagnetic behaviour. Thermogravimetric analysis (TGA) was indicated that thermal stability of PmPD/ZnCoFe2O4 NCs increases with increase in concentration of ZnCoFe2O4 NPs. The dielectric properties of PmPD/ZnCoFe2O4 NCs were also examined with different frequency.

Synthesis and characterization of Er2O3-doped Y2O3 nanoparticle incorporated optical fiber for use as optical amplifier

Erbium oxide (Er2O3)-doped optical fibers (EDF) are well-known for their applications in optical amplification at 1550 nm. In this study, we present the synthesis of Er2O3-doped yttrium oxide (Y2O3) nanoparticles (NPs) using a homogeneous coprecipitation technique and their integration into optical fibers for enhanced optical amplification. A series of NP samples with varying Y/Er molar ratios were synthesized to identify the optimal composition for incorporation into optical fibers. X-ray diffraction (XRD) analysis revealed that the nanoparticles crystallize in a cubic geometry (space group Ia3) with crystallite sizes ranging from 20 to 41 nm. These sizes increased approximately to 90 nm as the calcination temperature was raised from 1000°C to 1400°C. Field emission scanning electron microscopy (FESEM) corroborated the XRD results, while high-resolution transmission electron microscopy (HRTEM) confirmed the crystalline structure and an average particle size of approximately 100 nm. Photoluminescence studies showed that emission and excitation intensities were functions of the Y/Er molar concentration ratio and calcination temperature, with the lifetime extending up to 6.86 ms for a sample with a 0.25:0.01 Y2O3:Er2O3 ratio calcined at 1400°C. To assess the performance of the synthesized NPs, an optical preform was prepared using the Vapor Phase Delivery (VPD) method combined with the Solution Doping (SD) technique. The preform was then drawn into fiber, and its amplification performance was evaluated. The resulting fiber demonstrated efficient amplification with a gain of 14.9 dB with respect to 0 dBm input signal at 1550 nm under 150 mW pump power from 9 m active fiber, indicating its potential as a gain medium for constructing erbium-doped fiber amplifiers (EDFAs).