Williamson-Hall Models Research Articles

Synthesis of nano calcium silicates from waste calcite and aragonite phases for efficient adsorptive removal of industrial organic pollutants

The present study focuses on the adsorption efficacy of solid-state synthesized calcium silicate for removing congo red dye. Three different sources were used as calcium precursors; one was calcium carbonate, and the other two were natural waste sources, aragonite (P. globosa) and calcite (Eggshells). Structural analysis and functional groups of the samples were carried out by X-ray diffractometer (XRD), and a Fourier Transform Infrared Spectrometer (FTIR). Various well-known models/equations models such as the Liner Straight Line method of Scherrer’s equation (LSLMSE), Sahadat-Scherrer Model (SSM), Monshi-Scherrer model (MSM), Williamson-Hall model (WHM), Size-Strain plot method (SSP), and Halder-Wagner Model (HWM) were applied to compute the crystallite size of the synthesized calcium silicates; the estimated crystallite size range was 8–77 nm. The adsorption efficacy of the synthesized E-CaSiO3, S-CaSiO3, and C-CaSiO3 was assessed under various provisos for eradicating Congo red dye from wastewater. Computed results revealed that the dye removal percentages were approximately 100 % at 120 min and 200 rpm for 0.2 g E-CaSiO3. The point of zero charge evaluation showed that the pH of the adsorbents during maximum dye removal was 7 and was less than the value of pHpzc. Thermodynamics studies confirmed that the adsorption process was spontaneous. The method of adsorption of dye by the adsorbent was more clearly comprehended by Langmuir, Freundlich, and Temkin adsorption isotherm. 151.28 mg/g was the maximum adsorption capacity for S- CaSiO3 depending on the Langmuir isotherm model’s linear form (R2 = 0.924).

Green synthesis of nano-MgO using lemon juice for amplified photocatalytic degradation of organic pollutants

This study examines the photocatalytic activity of the green synthesized (using lemon juice) MgO nanoparticles under a halogen light for the degradation of Congo Red (CR). The characterization of the prepared sample was studied by applying Fourier Transform Infrared (FTIR) Spectroscopy, X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Thermogravimetric Analysis (TGA). By applying XRD analysis, the crystallographic variables of the MgO NPs were determined and the crystallite size was obtained from a variety of formulas/models (Scherrer equation, Williamson-Hall model, Monshi-Scherrer model, Size-Strain Plot, Halder-Wagner model, etc). The crystallite size was found in a valid range of 4.62–99.03 nm. Photocatalytic degradation of Congo Red (CR) has been made under halogen light by considering a dye concentration of 20 ppm at 40 mL solution for 0.05 g of the catalyst sample. Operating conditions were fixed as neutral pH, 25 °C temperature, and 40 min exposure time of the halogen lamp.

Influence of Lithium on Structural Properties of Lead Zirconium Titanate (PZT)

Lead Zirconium Titanate (PZT) is a potential piezoelectric material for sensor and transducer applications due to its outstanding piezoelectric coupling near the morphotropic phase boundary (MPB). This is because PZT can switch between tetragonal and rhombohedral phases. PZT is still considered to be one of the piezoelectric materials that has received the greatest amount of attention from researchers and is used the most frequently. Modification with Lithium will improve the piezoelectric properties. In this study, the structural properties and morphological studies of Lead zirconium titanate and Lead zirconium titanate with Lithium modification have been evaluated. Various Scherrer’s models and other models, such as the Williamson-Hall model and Size-strain plots model, were used to display the observed fluctuations in crystallite size. Morphological analysis was used to determine the particle size. Graphs showing the distribution of particle sizes were drawn.

A comparative approach for estimating microstructural characteristics of BaTi1−xZrxO3 (0.0 ≤ x ≤ 0.3) nanoparticles via X-ray diffraction patterns

Barium titanate materials are currently a special topic for scientific research due to their effective technological applications. The tetragonal BaTi1-xZrxO3 (0.0 ≤ x ≤ 0.3) nanoparticles (NPs) were synthesized using a modified citrate technique. The current work provides a comparative approach for the calculation of crystallite size, stress, strain, and elastic characteristics based on X-ray diffraction (XRD) patterns. Various models have been developed to analyze XRD data; these models differ in their assumptions, mathematical approaches, and the type of information they provide. The Scherrer model ignores lattice micro-structures that develop in nanostructures, such as intrinsic strain. To overcome such drawbacks, three Williamson-Hall models, (the uniform deformation model (UDM)), the uniform stress deformation model (USDM), and the uniform deformation energy density model (UDEDM) have been discussed. According to the USDM model, with increasing Zr ion concentrations, interplanar space increases, causing a drop in Young’s modulus. All the previous approaches take into account the diffraction angle (2θ)-dependent peak broadening, which is thought to represent a combination of size and strain-driven induced broadening.Graphical

Structural and dielectric analysis of Cu-doped NiCo2O4 nanoparticles synthesized by green synthesis approach

The synthesis process of nanoparticles profoundly influences the chemical and physical properties of materials. Green synthesis, utilizing plant extracts as precursor materials, presents an environmentally friendly approach for producing metal oxide nanoparticles. In this study, we synthesized copper-doped nickel cobaltite (Ni1-xCuxCo2O4, x = 0.5) nanoparticles via a green synthesis method employing aloe vera leaf extract. Analysis of the XRD pattern revealed the formation of cubic spinel Ni0.5Cu0.5Co2O4 nanoparticles well-crystalline in nature (space group: Fd-3 m), free from secondary impurity phases. Crystalline size, determined using Debye Scherrer, modified Scherrer, and Williamson-Hall models, yielded values of ∼ 27 nm, ∼ 35 nm, and ∼ 62 nm, respectively. Dielectric studies conducted at room temperature revealed a frequency-dependent increase in dielectric constant. At lower frequencies, tangent loss (tan δ) showed higher values, which gradually decreased as frequency increased. Additionally, the AC conductivity demonstrated a significant increase with higher external field frequencies.

Pioneering electrochemical detection unveils erdafitinib: a breakthrough in anticancer agent determination

The successful fabrication is reported of highly crystalline Co nanoparticles interconnected with zeolitic imidazolate framework (ZIF-12) -based amorphous porous carbon using the molten-salt-assisted approach utilizing NaCl. Single crystal diffractometers (XRD), and X-ray photoelectron spectroscopy (XPS) analyses confirm the codoped amorphous carbon structure. Crystallite size was calculated by Scherrer (34 nm) and Williamson-Hall models (42 nm). The magnetic properties of NPCS (N-doped porous carbon sheet) were studied using a vibrating sample magnetometer (VSM). The NPCS has a magnetic saturation (Ms) value of 1.85 emu/g. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses show that Co/Co3O4 nanoparticles are homogeneously distributed in the carbon matrix. While a low melting point eutectic salt acts as an ionic liquid solvent, ZIF-12, at high temperature, leading cobalt nanoparticles with a trace amount of Co3O4 interconnected by conductive amorphous carbon. In addition, the surface area (89.04 m2/g) and pore architectures of amorphous carbon embedded with Co nanoparticles are created using the molten salt approach. Thanks to this inexpensive and effective method, the optimal composite porous carbon structures were obtained with the strategy using NaCl salt and showed distinct electrochemical performance on electrochemical methodology revealing the analytical profile of Erdatifinib (ERD) as a sensor modifier. The linear response spanned from 0.01 to 7.38 μM, featuring a limit of detection (LOD) of 3.36 nM and a limit of quantification (LOQ) of 11.2 nM. The developed sensor was examined in terms of selectivity, repeatability, and reproducibility. The fabricated electrode was utilized for the quantification of Erdafitinib in urine samples and pharmaceutical dosage forms. This research provides a fresh outlook on the advancements in electrochemical sensor technology concerning the development and detection of anticancer drugs within the realms of medicine and pharmacology.Graphical

A comparative study in estimating of crystallite sizes of synthesized and natural hydroxyapatites using Scherrer Method, Williamson-Hall model, Size-Strain Plot and Halder-Wagner Method

In this study, an approach was made to create hydroxyapatite (HAp) crystals on nanoscale ranges from CaCO3 and H3PO4 utilizing a wet chemical process. Both fish and cow bones were used effectively for making bone powder as the natural sources of HAp. X-ray diffraction approach proved that powdered bone and HAp were in the crystalline phase. The determination of crystallite size in synthesized HAp crystals and bone powders was investigated using a range of techniques, including Linear Straight-Line Method (LSLM), Williamson-Hall Method (WHM), Size-Strain Plot (SSP), Halder-Wagner Method (HWM), and Sahadat-Scherrer Method (SSM). We also employed different Williamson-Hall models to quantify the stress and strain of the powdered materials for all diffraction peaks, including the Uniform Deformation Model (UDM), Uniform Stress Deformation Model (USDM), and Uniform Deformation Energy Density Model (UDEDM). Williamson-Hall is regarded as the best approach out of all of them since it was used to find the energy density, lattice stress, lattice strain, and crystallite size of the formed crystal. All the results from each model were compared to check the variation of analyzed data. The obtained results confirmed that there was an interrelation between the particle sizes of the Size Strain Plot and the Williamson-Hall method.

Synthesis of nano-crystallite hydroxyapatites in different media and a comparative study for estimation of crystallite size using Scherrer method, Halder-Wagner method size-strain plot, and Williamson-Hall model

Hydroxyapatite (HAp) [Ca10(PO4)6(OH)2] is remarkably similar to the hard tissue of the human body and the uses of this material in various fields in addition to the medical sector are increasing day by day. In this research, mustered oil, soybean oil, as well as coconut oil were employed as liquid media for synthesizing nanocrystalline HAp using a wet chemical precipitation approach. The X-ray diffraction (XRD) study verified the crystalline phase of the HAp in all the indicated media and discovered similarities with the standard database. Several prominent models such as the Scherrer's Method (SM), Halder-Wagner Method (HWM), linear straight-line method (LSLM), Williamson-Hall Method (W-M), Monshi Scherrer Method (MSM), Size-Strain Plot Method (SSPM), Sahadat-Scherrer Method (S–S) were applied for the determination of crystallite size. The stress, strain, and energy density were also computed from the above models. All the models, without the Linear straight-line technique of Scherrer's equation, resulted in an appropriate value of crystallite size for synthesized products. The calculated crystallite sizes were 6.5 nm for HAp in master oil using Halder-Wagner Method, and 143 nm for HAp in coconut oil using the Scherrer equation which were the lowest and the largest, respectively.

Green synthesis of Ag2O & facile synthesis of ZnO and characterization using FTIR, bandgap energy & XRD (Scherrer equation, Williamson-Hall, size-train plot, Monshi- Scherrer model)

A typical study has been performed for synthesizing Ag2O and ZnO nanoparticles. In our case, aloe vera extract was used as a reducing agent for synthesizing Ag2O. This green synthesis of silver oxide used silver nitrate (AgNO3) as a precursor material. On the other hand, the direct precipitation method was used for synthesizing zinc oxide nanoparticles, in which the precursor materials used were zinc nitrate hexahydrate (Zn(NO3)2·6H2O) and potassium hydroxide (KOH). Afterward, the characterization of these synthesized nanoparticles was done by the X-ray diffraction (XRD) method. Then, the crystal size, lattice strain, stress, and energy density of synthesized ZnO and Ag2O were determined by using XRD peak profile analysis. Among the various available models for determining these microstructural parameters, we explored the Scherrer model, the linear straight-line method of the Scherrer equation, the Monshi-Scherrer model, the Sahadat-Scherrer model, the Williamson-Hall model (including the uniform deformation model, the uniform stress deformation model, the uniform deformation energy density model), the size-strain plot method, the Halder-Wagner model, etc. By employing the crystal size values from these models, the accuracy and validity of crystals were also performed. The synthesized products were also characterized by the exploration of functional groups (by FTIR) and optical band gaps (by UV technique).

Optical and structural characterizations of NiO-doped PMMA films and fabrication of Ag/NiO-doped PMMA/n-Si/AuSb for analogue-digital switching applications

Herein, the authors report the NiO-doped PMMA nanocomposites fabrication process with different Ni concentrations of 0.001–10 wt% on pre-cleaned glass, ITO, and n-type Si via spin-coating technique. X-ray diffraction (XRD) was used to analyze the crystal structure of NiO in powder form and the NiO-doped PMMA nanocomposite thin films. The Rietveld refinement method was used to analyze the manufactured NiO's powder-form structural characteristics. The analysis data revealed a single phase of NiO nanoparticles with face-centred cubic of Fm-3m space group. The average crystallites' mean size and the microstrain value were determined based on the Williamson-Hall model and were equal to 32.47 ± 1.210 nm and 5 × 10−5, respectively. The FESEM micrographs illustrate dispersed cubic-shaped NiO grains in the PMMA matrix. The estimated energy gaps and the width of the localized energy states (Urbach tails) are plotted against the photon energy. The estimated energy gap, EgOp is increasing from 3.649 ± 0.003 eV to 3.782 ± 0.005 eV with increasing the NiO nanoparticles' doping ratio in the PMMA as a host insulating polymer. The fabricated Ag/NiO-PMMA (S4)/n-Si/AuSb heterojunction device revealed two different (HRS and LRS) resistance-switching behaviours. For second and third electrical (I–V) paths, the extracted magnitudes of the ideality factor are 2.397 ± 0.006 and 2.691 ± 0.003 and the calculated barrier height are 0.727 ± 0.004 and 0.886 ± 0.005, respectively. The interfacial electronics states NSS increasing from 6.58 × 1012 to 3.7 × 1014 cm−2.eV−1 and 3.48 × 1013 to 3.65 × 1014 cm−2 .eV−1 for the 2nd HRS path and 3rd LRS, respectively. The investigated hysteresis loop and the variation in interfacial electronics states reveal that the NiO-PMMA nanocomposite may be promising in non-volatile memory and electrical switching electronic devices.

Calculation of crystallite sizes of pure and metals doped hydroxyapatite engaging Scherrer method, Halder-Wagner method, Williamson-Hall model, and size-strain plot

This research paper dealt with the synthesis and characterization of pure and metal-doped hydroxyapatite covering an in-depth crystallographic analysis. The Scherrer equation, Linear Straight-Line Model, Munshi Scherrer Model, Uniform Deformation Model, Uniform Stress Deformation Model, Uniform Deformation Energy Density Model, Size Strain Model, Halder Wagner Model, and Sahadat Scherrer Model were engaged to estimate crystallite size as well as strain, stress, and energy density from few models. All the models were evaluated with their merits and demerits along with usefulness. All the mentioned models showed acceptable results as the crystallite size ranges were from 22 to 77 nm except Linear Straight-Line Model (revealed invalid results for all the synthesized samples). The modified Williamson-Hall model (Uniform Deformation Model, Uniform Stress Deformation Model, Uniform Deformation Energy Density Model) exerted strain, stress and energy density positive and negative. But Size Strain Model, and Halder Wagner Model resulted in only positive values.

Defect engineering for enhanced optical and photocatalytic properties of ZnS nanoparticles synthesized by hydrothermal method

Defect engineering is a promising method for improving light harvesting in photocatalytic materials like Zinc sulphide (ZnS). By altering the S/Zn molar ratio during hydrothermal processes, Zn and S defects are successfully introduced into the ZnS crystal. The band structures can be modified by adding defects to the crystal structure of ZnS samples. During the treatment process, defects are formed on the surface. XRD and Raman studies are used for the confirmation of the crystallinity and phase formation of the samples. Using an X-ray peak pattern assessment based on the Debye Scherer model, the Williamson-Hall model, and the size strain plot, it was possible to study the influence of crystal defect on the structural characteristics of ZnS nanoparticles. The band gap (Eg) values were estimated using UV–Vis diffuse spectroscopy (UV–Vis DRS) and found that the Eg is reduced from 3.28 to 3.49 eV by altering the S/Zn molar ratio. Photoluminescence study (PL) shows these ZnS nanoparticles emit violet and blue radiations. In keeping with the results of XRD, TEM demonstrated the nanoscale of the prepared samples and exhibited a small agglomeration of homogenous nanoparticles. Scanning electron microscopy (SEM) was used to examine the surface morphology of the ZnS particles. Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and X-ray photoelectron spectroscopy (XPS) were used to evaluate and validate the elemental composition. XPS results indicate the presence of defects on the prepared ZnS nanoparticles. For the investigation of vacancy-dependent catalytic activity under exposure to visible light, defective ZnS with different quantities of Zn and S voids are used as catalysts. The lowest S/Zn sample, ZnS0.67 and the highest S/Zn sample, ZnS3, show superior photocatalytic activity.

Investigation of hydrothermal growth time and temperature for optimized ZnO nanowire arrays toward photovoltaics

The challenge of meeting energy demands has led to the development of nanotechnology. Semiconductor nanowires are considered a promising option among various nanomaterials for efficiently capturing solar radiation in an axial geometry. This work presents the growth of ZnO nanowire arrays on seeded-coated glass substrates using a two-step hydrothermal method, by examining the effect of two crucial hydrothermal growth parameters: time and temperature of growth. X-ray diffraction (XRD) spectra showed the hexagonal wurtzite shape of the ZnO nanowires which displayed a preferred (002) axial orientation. To estimate the crystallite size, strain, stress, and energy density values, we used the Modified Williamson-Hall models. Scanning electron microscopy (SEM) observations showed that the growth time and temperature have a significant impact on the length and diameter of the nanowires, which increase with increasing time and temperature. A clear correlation was also observed between the diameter and density of the nanowires. Optical analysis showed that ZnO nanowires exhibited good transmittance of about 90% in the near ultraviolet and visible spectrum, but this decreased with increasing growth time and temperature. The measured bandgap energy showed a red shift, which confirmed its correlation with the structural characteristics. The improved optical and structural features of ZnO nanowires were analyzed with regards to their potential use in photovoltaics.

Structure based photocatalytic efficiency and optical properties of ZnO nanoparticles modified by annealing including Williamson-Hall microstructural investigation

Structural deficiency in annealed ZnO nanoparticles would be a critical concern for the optical properties and photocatalysis efficiency of ZnO. Therefore, the structure and microstructure of synthesized ZnO nanoparticles annealed at 500 °C, 700 °C, and 900 °C for 4 h have been analyzed by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and UV–visible Diffuse Reflectance Spectroscopic (UV–Vis DRS) techniques. Williamson-Hall and modified Williamson-Hall models have explored microstructural properties. The bandgap in ZnO decreases from 3.18 eV to 3.11 eV for annealing, which coincides with the assessed optical band edge approximately and the accumulation of particles observed from SEM images. Moreover, the redox potential has been calculated for annealed samples to perform the photocatalytic experiment. Additionally, the photocatalytic performance has been estimated from the degradation of UV irradiation through the studied samples. Finally, the sample ZnO annealed at 500 °C confirms maximum RhB degradation rate of 60.9% due to its lower particle size with a higher surface area. The ZnO-500 may be a potential photocatalyst material, including semiconducting properties.

A Phenomenological Study of Chromium Impurity Effects on Lattice Microstrains of SnO2 Nanoparticles Prepared Using Sol–Gel Technique

In this study, the effect of chromium impurities on the crystal structure and lattice microstrains of tin oxide nanoparticles was investigated. Pure SnO2 nanoparticles were synthesized and subjected to calcination at different temperatures. Additionally, various concentrations (5%, 8%, 10% and 15%) of Cr-doped SnO2 nanoparticles were prepared using the sol–gel technique and subsequently calcined at 550 °C. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) techniques were utilized to examine the structure and morphology of the doped nanoparticles. The XRD patterns of tin oxide nanoparticles with different percentages of chromium impurities showed a tetragonal structure without any additional phase. The TEM images of pure SnO2 nanoparticles showed a uniform distribution of size and shape, with relatively smaller sizes compared to Cr-doped nanoparticles. To investigate the peak broadening of Cr-doped SnO2 nanoparticles, the Halder–Wagner method and Williamson–Hall models were employed to examine the effects of crystallite sizes and lattice strain. The results showed that increasing the impurity has a dual effect on nanoparticle sizes. Increasing the chromium impurity up to 8% led to an increase in compressive stress caused by the substitution of Sn ions with Cr ions on the crystal structure of rutile, resulting in an increase in the magnitude of lattice strain. However, when the chromium impurity was increased up to 15%, interstitial doping was preferred over substitutional doping. The compressive stress was subsequently converted to tensile stress, requiring the system to spend some of its energy to overcome the compressive stress, with the remaining energy reflected in the form of tensile stress. Furthermore, Fourier transform infrared (FTIR) spectra were obtained for all of the samples, confirming the XRD analyses.

Degradation of methylene blue and rhodamine B by hollow ZnO microspheres formed of radially oriented nanorods

It is crucial to find effective solutions to environmental contamination that are also ecologically friendly. Zinc oxide (ZnO) is well-known as a good photocatalyst. In this work, ZnO microspheres were synthesized using the solvothermal technique. X-ray diffraction (XRD), UV-Vis, and scanning electron microscopy(SEM) were used to evaluate the structural, optical, and morphological features of ZnO microspheres . The hexagonal structure of ZnO was determined using XRD analysis. The crystal size of ZnO was calculated using XRD patterns and was found to be 44.27 nm by the Debye-Scherrer equation, 32.39 nm using the Williamson Hall model, and 9.92 nm by the Modified Scherrer formula. The SEM pictures of the manufactured ZnO revealed that it has a shape in the form of microspheres formed by the conjunction of hexagonal nanorods. The average diameter of these microspheres is 5.16 μm. ZnO has a band gap energy of 3.1 eV. The photocatalytic activities of ZnO microspheres against methylene blue and Rhodamine B dyes were examined. Under sunlight, photocatalytic removal rates for methylene blue after 90 minutes and Rhodamine B after 120 minutes were 98.95% and 98.62%, respectively.

Crystallographic characterization of naturally occurring aragonite and calcite phase: Rietveld refinement

This research has comprehended the crystallographic characterization of two naturally occurring calcium carbonates phases e.g. aragonite and calcite in Pila globosa (P. globosa) and eggshells respectively. The tools employed to confirm the phases of aragonite and calcite were X-ray diffractoion (XRD) and Fourier Transform Infrared (FT-IR) spectroscopy. Several important crystallographic parameters like crystallite size, lattice parameters, dislocation density, crystallinity index, microstrain, volume of the unit cell, relative intensity of a certain plane, preference growth, and specific surface area were taken into account while assessing the desired aragonite and calcite phases. A number of well-known models e.g. Straight-line model of the Scherrer model, the Monshi-Scherrer model, the Williamson-Hall model, the Sahadat-Scherrer model, and the three-peak model aided the estimation of crystallite size. In all the cases, the observed crystallite size of calcite was larger than that of aragonite. The percentage of calcite and aragonite in eggshell and P. globosa were assessed by Rietveld refinement method. Observed results revealed that 97.4% calcite and 2.6% aragonite phases are present in eggshell while in P. globosa these percentages exist inversely, i.e. 93.2% aragonite and 6.8% calcite phases.

Characterization and optimization of ZnS thin film properties synthesis via chemical bath deposition method for solar cell buffer layer

Zinc Sulphide is one of most studied semiconductor with wide band gap (3.5–3.9 eV) versatile material due to its physical and chemical properties. ZnS is a non-toxic material and a suitable candidate to be a buffer layer for heterojunction solar cells. In this study, Zinc Sulphide (ZnS) thin films were deposited by chemical bath deposition technique using Zinc Acetate Dihydrate [Zn (CH3COO)2. 2H2O] and Thiourea [CH4N2S]. The ZnS thin films samples were characterized by UV-Vis NIR Spectroscopy, X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDX), Fourier-Transform Infrared Spectroscopy (FTIR) and Thin-Film Measurement Instrument. FTIR spectra confirmed the presence of ZnS bond in the crystalline thin film. XRD data confirmed the cubic structure of the deposited thin film only when the amount of Thiourea was increased and the complexing agent Hydrazine Hydrate was replaced with Tri-Sodium Citrate. Crystallite size and strain were estimated using Debye-Scherrer model and Williamson-Hall model and lattice constant was estimated using Nelson-Riley plot. Otherwise, XRD showed the amorphous phase. UV-Vis data confirmed ZnS thin films as enough transmittive and it showed higher bandgap. Thin-Film Measurement Instrument was used to measure the thickness of the ZnS thin films. Synthesized ZnS thin films exhibited promising characteristics for using as the buffer layer of the heterojunction solar cells. Highlights • ZnS thin films were prepared successfully by simple, low cost and environment friendly chemical bath deposition method. • XRD measurement confirmed both Amorphous and Crystalline phase of ZnS thin films. • By changing the precursor only can be achieved crystalline phase from amorphous phase of ZnS thin film. • The amount of precursor and deposition conditions can be optimized to produce crystalline ZnS thin film.

Structural and magnetic quantification of rhombohedral – Orthorhombic phase transition in gadolinium substituted bismuth ferrite

Room-temperature X-ray diffraction (XRD), and High-resolution transmission microscopy (HR-TEM) were used to investigate the structural properties of multiferroic Bi1-xGdxFeO3 perovskites, (x = 0.00, 0.05, 0.10, 0.15, 0.20, 0.25 and 0.30). The system under investigation was synthesized through a citric acid-based auto-combustion technique. XRD analysis revealed that the pure bismuth ferrite and the gadolinium substituted bismuth ferrite up to x = 0.10 samples composed of a polycrystalline rhombohedral structure (space group R3c (161)), the samples with Gd concentration between x = 0.15 and x = 0.25 show coexistence of rhombohedral and orthorhombic phases. At the same time, Bi0.7Gd0.3FeO3 crystallizes in a pure orthorhombic structure (space group Pbnm (62)). The crystallographic parameters and the ratio of the two competed phases were estimated using Rietveld refinement of XRD data. Williamson-Hall model based on the refined XRD data was used to estimate the average crystallite length and the induced lattice strain. Furthermore, TEM and HR-TEM images coincident with the XRD results. Bi1-xGdxFeO3 nanoparticles display coupling interactions between weak ferromagnetism and canted antiferromagnets at room temperature. The magnetic properties were estimated by analyzing the M(H) hysteresis loops collected using a vibrating sample magnetometer (VSM). This study can sustain new strategies for tailoring new smart materials with different fascinating properties.

Synthesis of Bi2O3 NPs with polyethylene glycol and investigation of photodegradation of phenazopyridine in aqueous solution

The synthesis of Bi2O3 by a simple chemical route in the presence of polyvinylpyrrolidone (PP) as surfactant was studied. The sample was characterized by XRD, FTIR, and DRS techniques. Its pHpzc was estimated about 9.5. Crystallite size of the as-synthesized sample was estimated about 45 and 14 nm by the Scherrer and Williamson-Hall models, respectively. Band gap energy was estimated about 2.98 eV using the adsorption edge wavelength, while by using the Kubelka-Munk theory Eg-values of 3.21, 3.13, 3.27, and 3.24 eV were obtained for n-values of 2, 1/2, 3/2, and 3, respectively. The photocatalytic performance of the Bi2O3 NPs was evaluated against phenazopyridine as a model pollutant. Experimental optimized parameters were as adsorbent dosage = 0.7 g/L, contact time = 60 min, pH 7, illumination time: 60 min, CPP: 20 ppm. The photocatalytic kinetics model obeyed the pseudo-first order kinetic model.