Energy Dispersive X-ray Spectra Research Articles

Corrosion behavior and scratch performance of Al-WC nanocomposites

Corrosion behavior and scratch performance of Al-WC nanocomposites with varying wt% of WC are evaluated in this study. Liquid metallurgy-based stir-casting route is used for fabrication of the nanocomposites. Particles are distributed in the matrix as confirmed by EDAX (energy-dispersive X-ray) spectrum and XRD ( X-ray diffraction) analysis. The micro-hardness of nanocomposites increases with the increase of wt% of WC particles. Corrosion behavior is studied under different corrosive environments, viz., neutral, alkaline and acidic solution. Tafel plots and Nyquist plots are obtained under the neutral medium (3.5wt% NaCl aqueous solution), while only Tafel plots are obtained under 0.5M NaOH solution and 0.5M HCl solution. Among all three operating mediums, NaCl solution is the least corrosive for the composite. Corrosion rates under NaOH and HCl medium are high and values are very close to each other. The least amount of reinforcement, 0.5wt% of WC, yields the best corrosion resistance under the neutral solution. The corrosion resistance increases with the amount of reinforcement under alkaline and acidic mediums. From SEM (scanning electron microscope) images of the corroded surfaces, pitting corrosion is observed for Al-0.5%WC composite while exfoliation with deeper cracks is observed for composites with a higher amount of WC. Scratch performance is also evaluated for a load range of 5N to 20N. Scratch resistance increases with increase in wt% of nano-particles. Surfaces after scratching are characterized using optical microscope, SEM, and EDAX spectrum.

ESR and optical investigation of tetragonal PbTiO3 nanoparticles embedded in lithium tetraborate glass matrix

Glass-nanocomposites (GNCs) samples of composition [(100−x) Li2B4O7–xPbTiO3] with x = 5, 10, 15 and 20 mol% were prepared by melt quenching method. The two phases of the GNCs samples, a glassy phase and PbTiO3 nanoparticles/clusters phase, can be seen in the energy dispersive X-ray spectra and scanning electron microscopic micrographs. Fourier transformation infrared spectra of the GNCs samples exhibited bands due to triangular with NBO’s and tetrahedral borate groups. Additionally, the Ti4+ ions exist in both TiO4 and TiO6 structural units while the Ti3+ ions exist in TiO6 structural units. The electron spin resonance (ESR) spectra of the GNCs samples exhibit two ESR signals, broad and narrow, corresponding to the Ti3+ (3d1) ions in both tetragonal deformed octahedral and in the other structural configuration, respectively. The optical transmission spectra of the GNCs samples exhibited three transmission bands, 3Γ5 → 2Γ3, 2B2g → 2B1g and 2B2g → 2A1g transitions, in the visible region. The variation in optical band gap (Eopt) with increasing PbTiO3 content were due to the conversion between BO3 with NBOs and BO4 units as well as the reduction of Ti4+ to Ti3+ ions in the GNCs matrix. These results demonstrate that the present GNCs may be used for practical applications such as optical devices.

Studies on silver-doped magnesium ferrite utilizing the sol–gel process in terms of structure, magnetism, electricity, and electrochemistry

Silver added magnesium ferrite (Mg1-xAgxFe2O4) nanofine grains were prepared by the sol–gel technique from magnesium, silver, and ferrous precursor materials, maintaining the pH value that was subsequently investigated for sensing applications. X-ray diffraction (XRD) analysis of the ferrite samples showed (Mg1-xAgxFe2O4) cubic spinel structure, larger crystallite size, and other characteristics. Using Fourier transform infrared spectroscopy, the active and functional groups with potential stretching analysis were extracted (FTIR). Using an energy dispersive X-ray (EDAX) spectrum and a scanning electron microscope (SEM), the surface characteristics, features, and the samples purity were examined. The magnetic behavior was examined using the vibrating sample magnetometer (VSM) in relation to pertinent parameters like saturation magnetization (Ms), coercivity (Hc), and retentivity (Mr). It was found that the greater Ms in 1.0 is ferromagnetic. The LCR meter was used to estimate the dielectric constants (ε'&ε''), loss (tanδ) with AC conductivity (σAC), and cyclic-voltammetry was used to assess the electrochemical behavior of the samples. A study is conducted on potential polarizations at both ranges of frequencies. The acquired facts are thoroughly analyzed and comprehended.

Fabrication of CuO/Au Nanowires on a Copper Substrate for Ultra-Sensitive SERS Sensors

 To optimize the surface-enhanced Raman (SERS) phenomenon on the surface of noble metals, gold nanoparticles were synthesized on the surface of nano-sized copper wires to enhance the dispersion of gold particles on the research surface. A simple experimental procedure was carried out in two stages. First, the thin copper substrate was lightly oxidized with ammonium persulfate in an alkaline environment, then incubated at 200oC for 3 hours to form copper nanowires that exist stably on the substrate surface. Immediately afterward, highly uniform CuO/Au nanowires were formed by the chemical reduction of HAuCl4 on the surface of the oxidized copper plate. The results show that gold nanoparticles of about 5 nm were attached to CuO nanowires with a length of up to 10 µm and a diameter between 100 and 300 nm. The X-ray energy dispersive spectrum demonstrated a uniform distribution of gold particles. The CuO/Au structure was used as a SERS substrate to detect methylene blue at a low concentration of 10 pM corresponding to 2 signals at the peaks 1395 cm−1 and 1625 cm−1 as the C-H and C-C deformation vibrations of the aromatic ring. The logarithms of the methylene blue concentrations were linearly proportional to their SERS signal intensity of methylene blue at the peak of 1625 cm-1  with a value R2 = 0.96. The signals of SERS for methylene blue at twelve different points on the material sample showed no significant differences in both intensity and shape of the spectrum, with an RSD value of 5.9%.
  

Correlation between structural – Optical – Magnetic properties of cobalt based double perovskite, Sr2TiCo1-yO6-δ

The influence of charge disorders, non-stoichiometry and oxygen vacancy on the physical properties such as optical properties and magnetic properties of Sr2TiCo1-yO6-δ exhibiting simple cubic (space group Pm-3m) structure has been investigated in the article. An analysis of energy dispersive X-ray spectrum reveals a deficiency of cobalt ions. Variable range hopping conduction mechanism is observed below 100 K. X-ray photoelectron spectroscopy results indicated the presence of oxygen deficiency accompanied by multiple valent cobalt ions (Co4+ and Co3+) in the material. The optical features of the material are noteworthy, with a wide range of significant optical absorption occurring in the UV range, characterized by a band gap of ∼3.03 eV. In addition, huge photoluminescence emission in the visible range and at room temperature was observed. In this context, Sr2TiCo1-yO6-δ is a potential material for optical applications due to its high thermal stability with respect to temperature in air environment. Magnetic studies indicate the presence of mixed exchange magnetic interactions among the cobalt ions with different valence states generated during the synthesis. The weak ferromagnetic exchange interactions involved Co3+-O-Co4+ ions.

Improved humidity sensing performances of boron doped ZnO nanostructured thin films depending on boron concentration

Abstract This study details the production and analysis of undoped zinc oxide (uZnO) and boron (B) doped zinc oxide nanostructured thin films, with a specific focus on assessing the influence of varying B doping concentrations on humidity sensing performance. The synthesis of undoped ZnO and B doped ZnO nanoparticles was carried out using sol–gel method. B doping concentrations within the ZnO lattice were adjusted to 1, 3, 4, 5, and 10 mol%. Subsequently, nanostructured thin films were obtained through the spin coating technique on glass substrates. X-ray diffraction analysis revealed a hexagonal wurtzite structure for all nanostructured thin films. Notably, a change in preferential orientation from the (002) plane to the (100) plane occurred when B doping concentration exceeded 5 mol%. Scanning electron microscopy showcased nano-sized grains and capillary nanopores on the surface of each thin film. Energy dispersive X-ray spectra confirmed the presence of zinc, oxygen, and boron elements in the nanostructured thin films. Humidity sensing performance was assessed through electrical resistance measurements in the range of 45%–90% relative humidity at room temperature. All fabricated sensors exhibited sensitivity to humidity. Remarkably, the sensor with a 5 mol% B doping concentration demonstrated the highest humidity sensitivity (438.44 times) and the fastest response (2.0 s) and recovery times (14.2 s). The study concluded that the optimal B doping concentration for designing a highly efficient humidity sensor was determined to be 5 mol%. Overall, the study underscores the potential of B doped ZnO nanostructures for humidity sensor applications, given their exceptional sensor performance.

Investigation on structural, optical, thermal, and dielectric properties of cellulose propionate/styrene-maleic anhydride copolymer/molybdenum nanocomposite prepared by pulsed laser ablation

Polymer nanocomposite films of cellulose propionate/styrene-maleic anhydride copolymer/molybdenum (CP/SMAC/Mo) were fabricated by pulsed laser ablation of Mo in the polymer solution for 10, 20, and 30 min. The films were then characterized by various analytical methods. X-ray diffraction (XRD) revealed that the addition of Mo to CP/SMAC removed the crystalline peaks of Mo without changing the amorphous nature of the copolymer. According to the scanning electron microscopy (SEM) and atomic force microscopy (AFM) patterns, Mo atoms were trapped in the amorphous polymer stacks. The energy-dispersive X-ray (EDX) spectrum features C, O, and Mo. FTIR confirmed the embedding of Mo in the polymers. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) were carried out on the samples. The pristine polymer film exhibited a band gap energy of 2.9 eV, which decreased to 2.05 eV because of the loading of the Mo nanoparticles. The intensity of the photoluminescence (PL) peak of the films increases with ablation time such that the absorption intensity of the film at a λmax of 426 nm increases by trifold during the 30 minutes of irradiation, which is consequently due to the increased amount of Mo in the nanostructure. The incorporation of Mo in the polymer matrix enhances the dielectric constant (ε') (6.28-18.13) and ac conductivity (σac) (3.19 × 10−5-1.12 × 10−4 S/cm) of the polymer with negligible dielectric loss. The results suggest possible technological utilization of these materials in such applications as supercapacitors, light-emitting diodes, and organic optoelectronic devices, among others.

Green synthesis of CoFe2O4 nanoparticles assisted with bio-waste (Gomutram): Sintering effect on the properties of structural, microstructural and vibrational bands

Synthesis of CoFe2O4 nanoparticles has been effectively accomplished by the cow-urine (Gomutram) as a chelating agent. The liberation of hazardous gases during the sol-gel synthesis process are minimized using cow-urine (Gomutram) as a chelating agent. The Energy Dispersive X-ray Spectrum offers insights on the current composition of ferrite by providing information on the stoichiometric ratio of its constituent elements. The X-ray diffraction patterns provide substantiation for the formation of the spinel phase of present ferrite system. The ferrite systems that underwent sintering at lower temperatures exhibited a more conspicuous amorphous morphology. The experimental lattice parameter (a) and average crystallite size (D) were found to be within the range of 8.0688–8.3779 Å and 3.7–9.4 nm respectively. Both a and D demonstrate an augmentation in magnitude due to the heat treatment procedure. The function of activation energy in the ripening of crystalline size during the sintering process is significant particularly in relation to grain boundary energy. The aggregation of nanoparticles into large clusters can be attributed to the strong magnetic interactions present among them. The inherent characteristics of scanning electron micrographs unambiguously demonstrate. The vibrational frequencies (υ1 and υ2) observed from Fourier Transform Infrared spectra confirm the spinel phase of the present ferrite system. The changes seen in vibrational frequencies do not offer empirical support for the association between annealing and the expansion of the lattice constant. But, offers an empirical support for the hypothetical redistribution of cations in the spinel structure.

The influence of the physicochemical processes on the electrical response of Al/p-Si structure with etched surface

In this paper, the electrochemical etching process is used for surface modification of the p-Si wafer, named as porous silicon (PS), in the metal–semiconductor (MS) type Schottky diode (SD) with a structure of Al/p-Si. Five regions of PS wafer with different etching rates are selected for comparison of them which are called P2, P3, P4, and P5 (P1 is the reference area without porosity). The morphological, structural, and electrical properties of the PS used in the MS-type SD are investigated using field-emission scanning electron microscope (FE-SEM) images, energy dispersive X-ray (EDX) analysis, and current–voltage (I–V) characteristics, respectively. The FE-SEM images show a meaningful effect on the porosity. The EDX spectrum demonstrates the importance of the chemical effects in addition to the physical changes in the porosity process of the p-Si wafer. The reverse-saturation current (I0), ideality factor (n), barrier height at zero-bias (ΦB0), and series/shunt electrical resistances are also computed and compared. Some of these parameters (n, Rs, BH) are determined using different methods, namely Thermionic emission (TE), Cheung functions, and modified Norde, and they exhibit strong agreement with each other. The energy-dependent profiles of surface states (Nss) are estimated from the I–V data by considering the voltage dependence of ΦB (V) and n(V). All the experimental findings indicate that the etching process of the p-Si wafer significantly influences the electrical performance of the Al/p-Si Schottky diode by increasing the extent of etching.

Electrochemical behaviour of sputter-coated titanium films on AZ31 magnesium alloy

Lightweight magnesium-based structural alloy AZ31 is normally prone to high corrosion in an aqueous environment. A detailed study is reported in this work on AZ31 Mg alloy coated with Ti thin films of different thicknesses by DC sputtering to investigate the capability of Ti coating to prevent corrosion of AZ31 under an aqueous environment similar to seawater. Ti films have been fabricated to 50, 100 and 150 nm thicknesses. Utilising grazing incidence-XRD and SEM, the films’ structure and microstructure were studied. The films were amorphous. Due to corrosion, interesting micro-structures evolved. Corrosion inhibition characteristics of the Ti films were characterised by electrochemical techniques such as potentiodynamic polarisation and impedance spectroscopy. Ti films with 100 nm and 150 nm thickness show a good inhibition capability. The corrosion mechanism was investigated using XPS and X-ray energy dispersive spectra.

In-situ deposition of gold nanoparticles on screen-printed carbon electrode for rapid determination of Hg2+ in water samples

Herein, an electrochemical sensor for Hg2+ detection using in-situ deposited gold nanoparticles modified screen-printed carbon electrode (SPCE) was developed. The gold nanoparticles and Hg were co-deposited on the electrode during the enrichment process. Scanning electron microscope (SEM) and Energy dispersive X-ray (EDX) spectrum prove the successful modification of gold nanoparticles. After modification, the active surface area of the electrode enlarged, the electron transfer ability enhanced, and the detection of Hg2+ became possible. After comprehensive optimization of experimental parameters, the proposed sensor can achieve rapid detection of trace Hg2+ in drinking water through differential pulse stripping voltammetry (DPSV). The limit of detection reaches 0.33 μg/L, the linear range is 0.5–80 μg/L. The test can be completed within 5 min. This sensor does not require extra electrode modification before detection, which can simplify experimental steps and improve detection efficiency, holding great promise for the on-site detection of Hg2+ in environmental and food samples.

Development of Illite modified/Rh2O3 for electrochemical, sensor, photocatalysis and antioxidant studies

The present work revealed the development of illite modified/Rh2O3 nanocomposite through the reflux method. The modification of illite was achieved using CTAB (Cetyltrimethylammonium bromide) as a surfactant. The prepared nanocomposite was subjected to characterize X-ray diffractometer (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrum (EDAX), thermogravimetric analysis (TGA) and UV–visible spectroscopy techniques. The results exhibit that illite modified/Rh2O3 can successfully facilitate the photocatalytic degradation of orange G (96%) with excellent performance. Cyclic voltammetry analysis of the synthesized material was conducted using a carbon paste electrode in 0.1 M KOH electrolyte, revealing its significant redox potential output as determined by the CV technique. The composite material was used to detect the green sensors like bee pollen and cow urine confirming better sensing performance. Illite modified/Rh2O3 nanocomposite is used for free radical scavenging of DPPH (2,2-diphenyl-1-picrylhydrazyl) showed high antioxidant activity and IC50 value compared with illite and illite modified.

Development of a Biodegradable, Cytocompatible, Antibacterial, and Biofilm-Controlling Chitosan Sulfobetaine Derivative Film as a Biological Material

The purpose of this research was to develop a chitosan sulfobetaine (CS-SNCC) film via the solution-casting method as a biodegradable antibacterial material for biomedical applications. Chitosan and monochloro-triazine sulfobetaine were used as the raw materials for CS-SNCC preparation, and Fourier-transform infrared (FTIR), ultraviolet–visible (UV-Vis), energy-dispersive X-ray (EDX), and X-ray photoelectron spectroscopy (XPS) spectra were used to characterize and analyze the structure of the synthesized CS-SNCC. Furthermore, the swelling property, thermal stability, biodegradability, cytocompatibility, and antibacterial properties of the CS-SNCC film were comprehensively investigated and compared with those of the chitosan film. The results for the film’s enzymatic biodegradation behavior show that the CS-SNCC film undergoes a weight loss of 45.54% after 21 days of incubation. In addition, the CS-SNCC film effectively resists bacterial adhesion, prevents the formation of bacteria biofilms, and exhibits high antibacterial activity, with inactivation rates of 93.43% for Escherichia coli and 91.00% for Staphylococcus aureus. Moreover, the CS-SNCC film shows good cellular activity and cytocompatibility according to the cytotoxicity results. Therefore, the prepared biodegradable, cytocompatible, antibacterial, and biofilm-controlling CS-SNCC film has potential for biomedical applications.

The impact of methylene blue photosensitizer, aPDT and a calcium hydroxide-based paste on the physicochemical and mechanical characteristics of root canal dentin and the bonding interface of fiberglass posts

PurposeTo investigate the influence of methylene blue (MB)-mediated antimicrobial photodynamic therapy (aPDT) and calcium hydroxide (CH) medication on the mechanical characteristics, degree of conversion (DC), quantification, and volume of gaps at the adhesive interface of glass fiber posts (GFPs) luted to distinct thirds of root canal dentin. Additionally, the microhardness (MH), elastic modulus (Eit), morphology, and chemical structure of the intraradicular dentin were assessed. Materials and methods6 experimental groups were formed by sorting 102 bovine incisors. Canals receiving deionized water irrigation as a negative control; canals receiving deionized water irrigation and filled with CH as a positive control; groups treated with CH + MB at 50 and 100 mg/L without irradiation; and groups treated with CH + MB at 50 and 100 mg/L irradiated by red laser for 60 s (660 nm; 100 mW; 6.5 J; 72 J/cm2). MH, Eit, and DC properties were evaluated for both the resin cement layer and root dentin substrate (n = 8). Volume and quantification of gaps at the bonding interface (n = 6), and dentin morphology and chemical content were investigated (n = 3). Data were analyzed using a repeated-measures 2-way ANOVA followed by Tukey post hoc analysis (α = 0.05). ResultsThe distinct intraradicular thirds and treatment with MB-mediated aPDT, whether activated or not, in combination with CH, had a significant impact on the mechanical characteristics of the root dentin. This effect was also observed in the MH, Eit, DC, quantification, and volume of gaps at the luting interface (P < .05). In general, a higher concentration of MB, whether activated by a red laser or not, led to lower values in the mechanical properties of the root dentin, as well as in MH, Eit, and DC at the adhesive interface (P < .05). Additionally, these groups exhibited higher values for quantification and volume of gaps at the luting substrate (P < .05). Scanning electron micrographs and energy dispersive X-ray spectra showed qualitative similarity among all groups, except for the negative experimental control group. ConclusionsMB-mediated aPDT at 50 mg/L, in combination with CH, demonstrated favorable physico-chemical and mechanical characteristics in intraradicular dentin, along with satisfactory mechanical features and the adhesive interface integrity for GFPs at all intraradicular depths. Clinical significanceMB-mediated aPDT at a concentration of 50 mg/L combined to CH medication represents a suitable choice for photosensitization in the context of intracanal disinfection following the biomechanical procedure and prior to luting of intraradicular restorations.

Corrosion Evaluation and Inhibiting Effect of Chlorpheniramine Drug on Mild Steel in HCl Acid

The importance of non harmful inhibitors has informed the application of drugs as an agent to mitigate corrosion of metal materials. This research reveals the inhibitive reaction and adsorption mechanism of Chlorpheniramine drug (CD), on mild steel in an HCl solution using Potentiodynamic polarization, open circuit potential and weight loss method. The CD inhibitor was proportioned into 2.5, 5, 7.5, and 10ml while molarity of HCl was varied in the proportion of 0.1, 0.5, 1.0 and 1.5M at a temperature of 298 K. The reaction showed that as the CD concentration moves to higher concentration, the efficiency of the inhibitor increases, also the higher the concentration of the acid, the higher the corrosion rate. Observation from the result revealed that CD inhibitor protected the steel from corrosion destruction. The optimum efficiency occurred as 85.80% at 10ml CD concentration. CD inhibitor obeyed Freundlich law of isotherm with the average regression value of R2 = 0.9733, as R2 value gets close to unity. Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray spectra (EDX) results also confirm strong adsorption mechanisms of CD inhibitor on the mild steel samples. Keywords: Chlorpheniramine Drug; Green Inhibitor; Open circuit potential; Potentiodynamic Polarization; Mild steel

Green synthesis and anti-tumor activity of curcumin @ ZnO/CuO nanoparticles

Both zinc oxide and copper oxide nanoparticles are promising biologically active materials. Green synthesis approach was used to prepare mixed ZnO/CuO nanoparticles loaded with curcumin extract. The isolated mixed oxides loaded with curcumin (curcumin @ ZnO/CuO) was characterized by UV–visible spectra, FTIR spectra, X-ray powder diffractions (XRD),Transmittance electron microscope (TEM), Energy dispersive x-ray (EDX) and x-ray photoelectron spectroscopy (XPS) spectra. X-ray powder diffractions indicated that ZnO has wurtzite structure and CuO crystallizes in a monoclinic system. XPS confirmed the existence of both CuO and ZnO nanoparticles. TEM results indicated the formation of quantum dots of curcumin @ ZnO/CuO with size in the range 6–10 nm. The optical band gaps of curcumin @ ZnO/CuO were determined and found to be 3.4 and 4.05 eV, which are higher than the bulk. The effects of curcumin @ ZnO/CuO on hepatocellular (HEPG-2) and colorectal (HCT-116) carcinoma were estimated by cell viability, cell cycle and anti-apoptotic factors (caspase-3/7, topoisomerase 2beta and annexin). Strong cytotoxicity activity and apoptosis of tumor cells were observed for curcumin @ ZnO/CuO. The cytotoxicity of the current compounds showed higher activity in comparison with other compounds that were previously studied.

Thermal and mechanical properties of a sustainable bio-flax fibre-based lightweight aggregate concrete

A novel lightweight aggregate concrete (LWAC) or lightweight concrete (LWC) is developed using expanded perlite powder and lightweight expanded clay aggregate as a replacement for conventional fine and coarse aggregates, respectively. Furthermore, the natural plant-based flax fibre in treated form was added to the LWC mix at three different volume fractions. The mechanical and thermal characterisation of LWC was carried out using the compressive strength test, split tensile test, modulus of rupture, thermal conductivity and thermal resistance test. Moreover, the microstructural and durability properties were obtained using scanning electron microscopy/energy dispersive X-ray spectrum analysis, rapid chloride penetration test, sorptivity test and water absorption test. Test results reveal that the addition of 2.0% flax fibre resulted in improved mechanical, thermal and durability properties when compared to LWC with no fibres. Moreover, the microstructural analysis using SEM revealed the formation of ettringite which is responsible for the strength development in the LWAC mix.

Study of structural, dielectric, transport and optical properties of the CaMn0.94Ce0.06 O3 Ceramic

We report the structure, microstructure, dielectric, transport, and optical properties of the CaMn0.94Ce0.06O3 ceramic synthesized by the solid-state reaction method. Analysis of the X-ray diffraction (XRD) pattern of the sample adopts an orthorhombic crystal symmetry. A study of scanning electron microscope (SEM) micrograph shows the homogeneous distribution of the well-grown grains over the entire surface of the sample. The well-defined and distinct grain boundaries surrounding the compact grains may be a possible reason for a better conductivity mechanism in the sample. The study of the energy dispersive x-ray (EDX) spectrum provides information about the formation of high-purity samples and also confirms the presence of Ca, Mn, Ce and O in both weight and atomic percentages. The agglomeration rate during the sintering process may be a possible reason for a better dielectric and conductivity mechanism. Fourier-transform infrared spectroscopy (FTIR) study strongly supports the presence of all constituent element’s atomic vibration bands. The study of the UV visible spectra provides the idea of semiconducting nature and bandgap energy of 4.89 eV. At a low range of frequency, the presence of the Maxwell-Winger type of dielectric dispersion is confirmed. Dielectric properties were investigated, including conductivity, dielectric constant, dielectric loss, and complex modulus. According to impedance analysis, primarily the charge carriers’ long-range movement controls the conduction process. The semiconducting nature of the sample is confirmed by analysis of the Cole-Cole plots.

Photocatalytic degradation of acid blue 74 by Co: WO3 nanoparticles: Kinetics and response surface methodology studies

Energy-efficient sol-gel synthesis was achieved through the microwave assisted self-combustion route to produce hexagonal Tungsten oxide semiconductor (WO3). The photocatalytic activity was enhanced by doping Cobalt (Co) into the crystalline structure of the nanoparticle, which were subsequently sintered at 400 °C for an hour. The structural and morphological properties of the Co-doped WO3 were revealed using X-ray diffraction (XRD) characterization. The nanoparticles exhibited an amorphous structure before annealing, due to the short heating time during combustion synthesis. Sintering the nanoparticle transformed the nanoparticle from a monoclinic phase to orthorhombic phase structure. Additional analysis techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive X-ray spectrum analysis (EDS).To assess the photocatalytic performance of these particles, Acid Blue 74 (AB 74) was employed in photodegradation experiments under UV light irradiation within a semi-continuous reactor.The photodegradation of dye molecules was evaluated utilizing a UV–Vis spectrophotometer, and the mineralization efficiency of the dye was determined through total organic carbon analysis (TOC). The results indicated that the dimension of the synthesized nano catalyst fell within the range of 70–120 nm, and it exhibited the ability to completely degrade a solution with an initial dye concentration of 20 ppm within 60 min. Various parameters affecting the photocatalytic reaction, including the photocatalyst dosage, initial dye concentration, pH and temperature of the dye solution were also investigated. The experiments were designed using Response surface methodology (RSM), through which a mathematical model for the dye removal process was developed.

Enhancement in the Electrocatalytic and Optoelectronic Performance of Cost-Effective Counter Electrode VO2 for Dye-Sensitized Solar Cell (DSSC)

Dye-sensitized solar cells (DSSCs) have garnered significant attention in the scientific community for more than two decades due to their cost-effectiveness, convenient manufacturability, little toxicity, and straightforward preparation methodology. In this study, we present a cost-effective alternative to the platinum electrode for DSSCs, which serves as the counter electrode. The utilization of vanadium oxide nanoparticles as counter electrodes (CEs) in DSSCs has been the subject of research due to its enhanced stability, cost-effectiveness, and favorable photovoltaic characteristics. The device has been fabricated in configuration of fluorine-doped tin oxide (FTO)||TiO2||ruthenium (II) dye (N719)||iodide—triiodide electrolyte||VO2 (counter electrode)||FTO and investigate their photovoltaic performance. The utilization of X-ray diffraction (XRD) analysis has provided insights into the crystalline properties of VO2, indicating that it exists in a crystalline phase with a crystalline size measuring 43.19 nm and a lattice strain of 1.68 × 10−3. The utilization of a field emission scanning electron microscope (FESEM) that is equipped with an energy dispersive X-ray spectrum reveals a dense microstructure characterized by a uniform distribution of vanadium (V) and oxygen (O) across the whole surface. The Raman spectroscopic examination of VO2 reveals the existence of many Raman bands, thereby confirming the presence of the monoclinic phase. Cyclic voltammetry measurements were employed to investigate the catalytic activity of the CE toward the electrolyte. The photovoltaic performance of the manufactured device was examined by I–V measurement, revealing a notable open circuit voltage (Voc) and efficient power conversion efficiency when compared to the other materials that were evaluated.