Nickel Ion Concentration Research Articles

Metabolipidomic changes induced by dermal nickel penetration determined in an ex vivo porcine ear skin model.

Nickel is one of humans' most prevalent triggers of allergic contact dermatitis. However, the underlying mechanisms of this allergy still need to be fully understood. One aspect that has yet to be explored is the direct impact of common metal allergens on the skin's metabolites and lipids composition. Our study employed matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) to analyze spatially resolved metabolic alterations induced by nickel exposure. Cross-sections of ex vivo porcine ear skin exposed to increasing nickel (II) ion concentrations (17-167 μg/cm2) were measured with an AP-SMALDI5 AF ion source coupled to Q Exactive HF Orbitrap mass spectrometer. Additionally, the penetration of nickel ions into the skin was observed through its pink complexation with dimethylglyoxime under light microscopy. For nickel ion concentrations up to 84 μg/cm2, most nickel ions were stopped within the stratum corneum, while only a very small proportion of nickel ions penetrated the viable epidermis and dermis. Stratum corneum locations with high nickel ion concentrations showed a decrease in arginine and ceramides. Furthermore, several phosphatidylcholine and sphingomyelin species were found to be downregulated in the viable epidermis and dermis due to the nickel exposure. Nickel penetrates at a trace level into the viable skin and induces severe metabolomic and lipidomic changes in the stratum corneum, epidermis, and dermis, indicating a change in the skin (barrier) function. These findings contribute to a deeper understanding of nickel-induced skin allergies and provide a solid foundation for further research.

Analysis of NCM concentration and extraction efficiency in the lithium-ion battery extraction process

In recent years, with the increasing popularity of portable electronic devices (PEDs) and electric vehicles (EVs), the demand for lithium-ion batteries (LIBs) has continued to expand; however, the supply of raw materials such as nickel cobalt, and manganese (NCM) is limited, and it is essential to develop efficient recycling technologies. Hydrometallurgical methods, particularly extraction processes, can be used to obtain high-grade recycled LIB products with proper control of the process window. This study focused on the separation of NCM from copper (Cu) and aluminum (Al) by diluting the metal concentrations ([Me]) and adjusting the pH (using NH4OH) during extraction. For metal composition analysis, in addition to using inductively coupled plasma mass spectrometry (ICP-MS), ultraviolet–visible (UV–Vis) spectroscopy and colorimetric analysis were also employed to monitor ion concentrations. The change in solution color is directly related to the nickel (Ni) and cobalt (Co) ion concentrations. Moreover, a continuous shift in the Ni ion absorption spectra at different pH values did not occur for the Co ion absorption spectra. According to the extraction efficiency (EE%) results, the lower [Me] resulted in the higher EE% of NCM. The optimal process window was established within the range of 0.025–0.1 M and pH = 6.5–7.4.

Structural, magnetic and electrical studies on nickel doped copper ferrite synthesized using sol-gel method

Nickel doped copper ferrite nanoparticles NixCu1-xFe2O4(x = 0.1, 0.3, 0.5, 0.7, and 0.9) have been prepared through well known sol-gel technique. Numerous analytical methods, including the Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), and powder X-ray diffractometer (XRD), were used to analyze the synthesized materials. Synthesized sample XRD patterns reveal the single phase development of the spinel crystalline structure in the absence of any contaminant. The concentration of Ni ions rises with a corresponding decrease in crystallite size. Scanning electron microscopy (SEM) was also used to assess the microstructure. By using UV–Visible spectrometer an optical absorbance and through FTIR, two of ferrite's distinctive bands were verified. The M-H loops show that when the concentration of nickel ions increases, saturation magnetization varies. The Cyclic-Voltameter was used to perform the ionic electrochemical analysis. The NixCu1-xFe2O4 nanopowder's enhanced magnetic characteristics suggest that these substances would make good candidates for magnetic catalysts.

Removal of Chromium ions (Cr6+) and Nickel ions (Ni2+) from Simulated Industrial Wastewater Using Flow-by-Porous Electrode

The quality of water is significantly impacted by the presence of Cr6+ and Ni2+ ions. This study investigates the effectiveness of a flow-by porous graphite electrode cell in removing these contaminants from simulated industrial wastewater. We explore the impact of various factors on the removal process, demonstrating the method's potential for efficient removal. The initial concentration of nickel and chromium ions (20 to 80 mg/l and 20 to 100 mg/l, respectively), the feed flow rate (0.28 to 1.11 ml/s), current density (0.2 to 2.25 mA/cm2) and pH all influence the removal rate and efficiency. A higher feed flow rate negatively affects the removal efficiency of both Ni2+ and Cr6+ ions. Nickel removal efficiency decreased by 34.9% at 20 ppm and 26% at 80 ppm, representing the highest and lowest reductions in efficiency, respectively. Chromium removal efficiency decreased by 19% at 100 ppm and 6.5% at 50 ppm, indicating the highest and lowest reductions in efficiency, respectively, under the same flow rate change. Under optimal conditions, the removal efficiency for Ni2+ was 99.47% after 15 min of operation at a current density of 1.96 mA/cm2, a flow rate of 0.28 ml/s, and a pH of 8 and the removal efficiency for Cr6+ was 99.97% after 10 min of operation at a current density of 2.25 mA/cm2, a flow rate of 0.28 ml/s, and a pH of 2. The flow-through porous electrode system achieves efficient heavy metal removal with operating costs of 0.24 USD/m3 for nickel and 0.38 USD/m3 for chromium at optimal conditions.

Structural and optical properties of Ni-doped ZnO thin films as TCO material, fabricated by pulsed laser deposition method

Thin transparent layers of zinc oxide doped with nickel ions were obtained using the pulsed laser deposition method. The content of nickel ions in the initial solid solution was 1–10 %. The crystallographic structure was studied by X-ray diffraction. Measurements show that the fabricated layer crystallizes in the wurtzite phase and has a dominant orientation along the c-axis. The texture coefficient, grain size, and crystal lattice constants were calculated. The absorption coefficient of the layers was calculated from the transmission spectra of ultraviolet–visible light - near infrared. Photocurrent spectra were investigated. The composition of the layers significantly affects the optical constants. Ni-doped ZnO layers can find applications in optoelectronic devices.

Elimination of nickel and chromium(VI) ions from industerial wastewater by electrodialysis/characteristics/impact of parameters

<p>Healthy water is a concern for the world due to rapid population growth and technological advancement. The entry of heavy metals into water as a result of various activities causes water pollution that has persistent effects. In this study, a specially designed electrodialysis cell was used to remove chromium (VI) and nickel ions from wastewater. The chambers were partitioned by Ionac MC 3470 cation exchange and Ionac MA 3475 anion exchange membranes. The cathode and anode were made of carbon fiber and stainless steel, respectively. The effects of voltage, initial pH, time, Na2SO4 concentration, feed flow rate and metal ion concentration on metal removal efficiency, energy consumption, current efficiency, current density and flux were investigated. Optimum values for 98.5% removal of 80 mg/L Cr(VI) ion in 90 min voltage 30 V, pH=3, addition of Na2SO4 0.5 g and feed flow rate 52. 8 ml/min, as observed. At the end of this period, concentration 1 mg/L, energy consumption 40 W/L, flow efficiency 30% and flux 12 x 10.-5 mol/m2s were calculated. Optimum values of 25 V, pH=3, addition of Na2SO4 0.2 g and Qf = 42.6 mL/min were observed for 94.3% removal of 50 mg/L Ni2+ ions in 90 min. At the end of this period, the nickel ion concentration was 4 mg/L, the energy consumption was 34 Wh/L, the flow efficiency was 96.51%, and the flux was calculated as 40×10-5 mol/m2s. This study shows that the electrodialysis method can be effectively used to elimonation chromium (VI) and nickel (II) ions from dilute wastewaters.</p>

A hybrid system for Nickel ions removal from synthesized wastewater using adsorption assisted with electrocoagulation.

The presence of heavy metal ions in water environments has raised significant concerns, necessitating practical solutions for their complete removal. In this study, a combination of adsorption and electrocoagulation (ADS + EC) techniques was introduced as an efficient approach for removing high concentrations of nickel ions (Ni2+) from aqueous solutions, employing low-cost sunflower seed shell biochar (SSSB). The combined techniques demonstrated superior removal efficiency compared to individual methods. The synthesized SSSB was characterized using SEM, FT-IR, XRD, N2-adsorption-desorption isotherms, XPS, and TEM. Batch processes were optimized by investigating pH, adsorbent dosage, initial nickel concentration, electrode effects, and current density. An aluminum (Al) electrode electrocoagulated particles and removed residual Ni2+ after adsorption. Kinetic and isotherm models examined Ni2+ adsorption and electrocoagulation coupling with SSSB-based adsorbent. The results indicated that the kinetic data fit well with a pseudo-second-order model, while the experimental equilibrium adsorption data conformed to a Langmuir isotherm under optimized conditions. The maximum adsorption capacity of the activated sunflower seed shell was determined to be 44.247mg.g-1. The highest nickel ion removal efficiency of 99.98% was observed at initial pH values of 6.0 for ADS and 4.0 for ADS/EC; initial Ni2+ concentrations of 30.0mg/L and 1.5g/L of SSSB; initial current densities of 0.59mA/cm2 and 1.32 kWh/m3 were also found to be optimal. The mechanisms involved in the removal of Ni2+ from wastewater were also examined in this research. These findings suggest that the adsorption-assisted electrocoagulation technique has a remarkable capacity for the cost-effective removal of heavy metals from various wastewater sources.

Correlation between the micro-shot peening coverage and surface microstructural evolution and fluoride-induced corrosion behavior in Monel 400 alloy

This study examines the influence of micro-shot peening (MSP) on Monel 400 alloy, focusing on surface microstructural evolution and fluoride-induced corrosion behavior compared to its solution annealed (SAed) counterpart. MSP treatments were conducted at various surface coverages (100%, 200%, 500%, 1000%, 1500%, and 2000%). Characterization encompassed microhardness, surface roughness, grazing incidence x-ray diffraction (GI-XRD), field emission scanning electron microscopy (FE-SEM) with electron backscatter diffraction (EBSD), and transmission electron microscopy (TEM). With increasing the MSP coverage to 2000%, the surface crystallite size decreased from approximately ∼30 µm in the SAed sample to 60 nm. TEM analysis emphasized dislocation slip and formation of dislocation structures as the primary mechanisms for the grain refinement. However, the 2000% coverage exhibited microcrack formation, compromising its hydrofluoric (HF) corrosion resistance. Electrochemical tests revealed severe localized corrosion in all MSP-treated samples except the 1500% coverage, which exhibited a minimum passive current density of 0.2–1.0 µA/cm2. Inductively coupled plasma optical emission spectroscopy (ICP-OES) of immersion solutions showed lower copper and nickel ion concentrations (<150 ppm) in the 1500% MSP-treated sample, indicating its enhanced corrosion resistance. X-ray photoelectron spectroscopy (XPS) identified NiO, NiF2, CuO, CuF2, and Cu(OH)2 phases in SAed and 1500% MSPed samples, with a higher concentration of copper oxide (CuO) in the corrosion film of the 1500% MSP-treated sample, contributing to its superior corrosion resistance.

Removal of Ni(II) ions from wastewater by ion exchange resin: Process optimization using response surface methodology and ensemble machine learning techniques

This study investigates the removal of nickel ions from aqueous solutions using Amberlite IR120 Na resin. Response surface methodology (RSM) and Ensemble machine learning models were employed to predict and evaluate the adsorption capacity of the resin. The effects of the initial concentration of nickel ions (10–90 mg/L), resin dose (0.1–0.7 g/L), initial pH (3−9), and temperature (10–40 ºC) were analyzed as independent variables. In order to assess the efficiency of Ensemble models, five methods, including random forest, extra tree, AdaBoost, gradient boosting, and XGboost models, were employed. The results demonstrated that the XGboost model predicts the adsorption capacity of the resin for Ni(II) with very high accuracy in the training phase (R2 = 1) and the test phase (R2 =0.96). The maximum adsorption capacity of the resin in the optimization step was achieved for CCD (initial Ni(II) concentration of 45.69 mg/L, resin dose of 0.1 g/L, pH of 6.64, and temperature of 39.68 ºC) and Bayesian optimization (initial Ni(II) concentration of 54.78 mg/L, resin dose of 0.11 g/L, pH of 4.72, and temperature of 39.02 ºC) techniques by 142.67 mg/g and 139.60 mg/g, respectively. Moreover, the Bayesian optimization method resulted in a lower error (0.63 mg/g) than the CCD model (1.53 mg/g). Based on statistical measures, it can be concluded that XGBoost outperforms CCD.

Synthesis of nanocrystalline nickel via pulsed current electrodeposition in additive-free deposition bath and comparison of nanoscale characterization

An experimental investigation on synthesis of nanocrystalline nickels by pulsed current electrodeposition has been carried out in an additive-free Watts bath employing nickel-sulphate solution with similar nickel ion concentrations. Aluminum was used as a substrate. It demonstrated the advantage of easier removal process of electrodeposited nanocrystalline nickel from its substrate. Whereas the use of high-purity nickel anode was intended to replace nickel ions, which decreased during electrodeposition. Different peak current densities of 450, 750 and 1000 mA/cm2 were applied. A pulsed current was set at a similar pulse pattern of on-time and off-time of 1 ms and 9 ms respectively. The shorter on-time demonstrated the ability to limit ion deposition, which was related to the formation of finer grains. The off-time arrangement was targeted to ensure that the ion mobility had completely stopped. Higher current density demonstrated a dominant impact on deposits, generating a higher nucleation rate that is related to depositing nanocrystalline nickel. A peak current density of 1000 mA/cm2 produced grain sizes in the nanoscale regime. Without any additional additive, nanocrystalline nickel was successfully yielded. Investigation of grain size obtained from the 1000 mA/cm2 has been conducted by extracting full width at half maximum peak intensity (FWHM) revealed from X-ray diffraction (XRD) and Transmission Electron Microscopy (TEM) exhibited consistent results of 22 nm and 25.4±3.4 nm, respectively. It is also evidence of the significant role of pulsed current density. In inclusion, nanocrystalline nickel can be synthesized in an electrodeposition bath without any addition of additives

A novel "off-on" fluorescent probe for the detection of nickel ions and its clinical application.

Nickel serves as an essential micronutrient for the human body, playing a vital role in various enzymatic processes. However, excessive nickel entering the environment can cause pollution and pose serious risks to animals, plants, and human health. High concentrations of nickel ions in the human body increase the risk of various diseases, highlighting the need for accurate measurement of nickel ions levels. In this study, we designed a sequence-specific cleavage probe for nickel (II) ion called SSC-Ni. Similar to the TaqMan probe, SSC-Ni is an off-on fluorescent probe with an exceptionally low background fluorescence signal. It exhibits high detection specificity, making it highly selective for nickel ions, and the detection limit of the probe towards Ni2+ is as low as 82nM. The SSC-Ni probe can be utilized for convenient and cost-effective high-throughput quantitative detection of nickel ions in serum. Its user-friendly operation and affordability make it a practical solution. By addressing the lack of simple and effective nickel ion detection methods, this probe has the potential to contribute significantly to environmental monitoring and the protection of human health.

Adsorption of Ni2+ by functionalized hydroxyapatite-chitosan composite

Abstract Chitosan and hydroxyapatite are commonly used materials for adsorption. In this work, chitosan was modified by polyethylene glycol and maleic anhydride. Subsequently, a hydroxyapatite-chitosan composite was synthesised by precipitation. The composite was characterised and analysed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). Adsorption experiments were used to investigate the effects of external factors such as different pH values, adsorbent dosage, adsorption time and initial nickel ion concentration on the adsorption capacity of Ni2+ and to discuss the mechanism of Ni2+ removal by composites. The results show that the hydroxyapatite-chitosan composite has significant adsorption of Ni2+. The adsorption capacity of the hydroxyapatite-chitosan composite for Ni2+ reaches 63.8 mg g−1. The adsorption process is consistent with the pseudo-second-order kinetic model and the Langmuir isothermal model.

ZIF-67 derived lamellar nanoarray spinel as effective catalyst for toluene combustion

Active sites exposed to the surface of solid catalysts play a significant role in heterogeneous catalysis. In order to aggrandize the exposure of active sites by enhancing catalyst specific surface area, a hierarchically structured nanoarray that nickel–cobalt spinel oxide regularly arranged on the hollow polyhedral structure surface in vertical orientation was successfully designed. Moreover, the effect of nickel ions concentration on the surface defects of the catalyst was studied, and Ni-Co-2:1 sample possesses optimal catalytic activity, achieving 90% toluene conversion at 257 °C.

Effect of Nickel Ions Substitution on the Magnetic and Optical Properties of a Nanosized Lithium-Iron Ferrite

This paper reports on the successful synthesis of fine nanoparticles of nickel-substituted lithium-iron ferrites of composition Li0.5-x/2NixFe2.5-x/2O4 (0.2≤ x ≤1.0) by the sol-gel autocombustion method. It has been found that the alternating current (AC) and direct current (DC) conductivity is preferably tuned due to its dependence on temperature and nickel doping. Analysis of the Arrhenius dependences also confirms the appearance of more than one conduction mechanism upon substitution. The predominance of one type of conductivity over another depends on the concentration of the substituting element. Measurement of the magnetic properties has shown that the substitution of Ni2+ can significantly change the saturation and residual magnetization. Samples of composition Li0.4Ni0.2Fe2.4O4 have the highest saturation magnetization (84.08 emu/g), residual magnetization (15.85 emu/g), and the lowest coercive force (0.18 kOe). All the obtained results indicate a significant effect of the substitution of Ni2+ ions on the structure and properties of Li0.5-x/2NixFe2.5-x/2O4 ferrite nanoparticles.Photocatalytic properties have been obtained by the degradation of Methylene Blue dye under illumination with a halogen lamp. It is shown that an increase in the content of nickel ions leads to a change in the type of conductivity: from n-type (unsubstituted lithium pentaferrite) to p-type (with substitution x = 0.8 and higher). These systems are characterized by hopping conduction realized by octa-positions according to the mechanisms Fe3++e-↔Fe2+, and Ni3+↔Ni2++h+. The predominance of one or another mechanism depends on the content of nickel ions. The optical band gap ranges from 1.4 to 2.25 eV. Samples with nickel content x = 0.4 and x = 0.8 have shown the best degradation ability, which is 97% within 160 min for Methylene Blue.

Multi-scale analysis of nickel ion tolerance mechanism for thermophilic Sulfobacillus thermosulfidooxidans in bioleaching.

Bioleaching is intensively investigated for recovering valuable metals such as Li, Co, Ni and Cu. Nickel ion stress threatens the health of microorganisms when Ni2+ starts to accumulate in the leachate during the bioleaching of materials that are rich in Ni, such as spent lithium-ion batteries. The possible mechanisms underlying the response of S. thermosulfidooxidans to nickel ion stress were analyzed using a multi-scale approach. Under the condition of nickel ion stress, high concentrations of nickel ions were immobilized by extracellular polymeric substances, while concentrations of nickel ions inside the cells remained low. The intracellular adenosine triphosphate (ATP) concentration and H+-ATPase activity increased to maintain normal cell growth and metabolic activities. Scavenging abilities of S. thermosulfidooxidans for hydrogen peroxide and superoxide anion were enhanced to reduce oxidative damage induced by nickel ion stress. There were 734 differentially expressed genes identified by RNA-seq under nickel ion stress. Most of them were involved in oxidative phosphorylation, glutathione metabolism and genetic information processing, responsible for intracellular energy utilization, intracellular antioxidant capacity and DNA damage repair, respectively. The results of this study are of major significance for in-depth understanding of the mechanisms of acidophilic microorganisms' resistance to metal ions.

Disposal of used nanosorbents obtained during wastewater purification from Ni2+ ions in powder paint materials

The prospects of increasing the level of environmental safety of industrial enterprises as a result of the implementation of the latest sorption technologies for wastewater treatment are considered. An analysis of the effectiveness of the existing methods of sorption water purification, which contain compounds of heavy metals, was carried out. Highly effective magnetic sorbents were obtained by electroerosion dispersion, which contains polyvalent iron oxides.&#x0D; The effect of the method of introducing the sorbent into wastewater on the degree of its purification was investigated. The most effective results in water purification were achieved with the use of freshly obtained powder of electroerosion dispersion of iron in water in the form of a suspension, which allows to achieve a high degree of water purification from zinc ions - more than 99%. Such water meets the standards for washing parts in galvanic production with regard to the content of nickel ions. The expediency of recycling spent nano-sorbents in the composition of powder paint and varnish materials is shown. When a coating chemically stable in water treatment waste, which has ferromagnetic properties, is included in the composition, in quantity15% by weight high corrosion resistance of the coating is ensured and shielding of electromagnetic radiation increases approximately 3 times compared to the standard sample. The use of research results at enterprises will prevent environmental pollution with toxic substances, change outdated production technologies, ensure efficient and rational use of water, raw materials and energy in the industrial production system.

Treatment of synthetic zinc and nickel wastewater and identification of its crystallization products by fluidized bed homogeneous crystallization technology

Heavy metals such as zinc and nickel can be found in wastewater from steel electroplating trace concentrations. These heavy metals harm the ecosystem and human health, which must be addressed. This study aimed to use fluidized bed homogeneous crystallization process (FBHCP) to recover nickel-zinc crystal from simulated electroplating wastewater. The best-operating conditions include a 10.2 initial pH of the crystallization reagent, variable nickel ion concentrations of 200 – 500 mg·L−1, and variable zinc ion concentrations of 100 – 400 mg·L−1. The nickel-zinc solution has a starting concentration of 300 mg L−1 of both nickel ions and zinc ions and a 1.75 molar ratio (MR) of [CO32-]/[Ni2++Zn2+]. The highest removal rate for zinc was 99.6 %, and for nickel was 88.7 %. According to SEM morphology, the crystals generated have a high-density smooth crystal with pores. According to XRD analysis, the crystals generated were layered hydroxide salts (LHS) of nickel-zinc with the structural formula. FBHCP was employed to successfully recover NiZn – LHS crystals from simulated wastewaters, which can now be utilized for future adsorption applications.

Recovery of nickel from electroless nickel plating wastewater based on the synergy of electrocatalytic oxidation and electrodeposition technology.

Nickel exists primarily as a stable complex in electroless nickel plating wastewater, and the Ni recovery from it cannot be achieved solely through electrodeposition. As the electrocatalytic oxidation has excellent oxidation potential to break down the complex, an efficient and stable electrochemical system using the synergy of electrocatalytic oxidation and electrochemical deposition technology was developed for the recovery of nickel from electroless nickel plating wastewater. In the present study, the effects of initial pH, current density, and initial nickel ion concentration on the treatment performance of the electrochemical system was investigated. The highest Ni recovery (94.84%) and total organic carbon removal (63.94%) were achieved at a current density of 83.3mA/cm2 , initial pH of 3.0, and initial Ni concentration of 0.01 M. At the same time, the recovered nickel product was confirmed by scanning electron microscopy, energy dispersive X-ray, X-ray powder diffraction, and X-ray photoelectron spectroscopy. Furthermore, the electrochemical system displayed good stability and economic benefits, thereby suggesting its excellent application potential for the treatment of electroless nickel plating wastewater. PRACTITIONER POINTS: An efficient and stable electrochemical system was developed for the recovery of nickel from electroless nickel plating wastewater. In an acidic medium, the nickel recovery rate and TOC removal ratio were 94.84% and 63.94%, respectively. The system displayed good stability, thereby suggesting its excellent application potential for the treatment of nickel plating wastewater.

Detailed analysis of structural, optical and photo catalytic properties of spinel nickel doped magnesium zinc ferrites at different substitutions

Spinel nickel doped magnesium zinc ferrite nanoparticles under different substitutions have been prepared using co-precipitation technique. The characterization studies which include crystallite size, crystalline solid structure and optical properties of the prepared nanoparticles were examined using x-ray diffraction (XRD), fourier transmission infrared spectrum (FTIR), scanning electron microscope (SEM) and absorbance that was measured by ultraviolet visible (UV) spectroscopy. As increasing the Ni concentration, the optical band gap increases from 3.32 eV to 4.57 eV. In this research work, the photocatalytic assessment of Ni-added-Mg-Zn nano-ferrites has been investigated by using bulb light degradation (methylene blue dye (60 W) method. Mg0.5Zn0.5-xNixFe2O4 spinel nano-ferrites (x = 0.125, 0.250, 0.375) were produced by co-precipitation method. The photocatalytic study has been reported by analyzing the degradation of methylene blue dye under sunlight irradiation. The better-quality photocatalytic activity with increased Ni content was investigated for the samples under study for a 40-minute exposure of × = 0.125, a maximum degradation efficiency of 61 precent was acquired. The phase-change was appeared due to shifting of peaks to the higher angle in Mg-Zn ferrite samples as a result of increments in Ni contents. According to vegard's law, the lattice parameter (a) of the crystal increases with increasing the concentration of nickel ion. Phase identification of magnesium-zinc ferrite nanoparticle was done by using X-ray diffraction (XRD).

Effect of nickel ion concentration on structural, optical and electrical properties towards Ni–H3BTC-MOF formation for nonlinear saturable absorption phenomenon

Metal-organic frameworks (MOFs) are a class of crystalline hybrid porous materials that have drawn considerable research interest owing to their tunable characteristics and wide range of applications. In this study, we investigated the effect of the nickel ion concentration on the structural, optical, and electrical properties of Ni–H3BTC-MOF for the potential nonlinear saturable absorbance phenomenon. Structural analysis was performed using Fourier transform infrared spectroscopy, X-ray diffraction and Brunauer–Emmett–Teller analysis, whereas diffuse reflectance UV–Vis–NIR spectroscopy was used to characterize the optical properties. The AC transport properties of the as-prepared Ni–H3BTC-MOF were investigated using electrical impedance spectroscopy. It was found that the porosity increased with an increasing concentration of nickel ions. In contrast, the real permittivity and loss tangent decreased. The highest modulation depth obtained was 4.48% for the sample with a nickel ion concentration of 2 mmol. This performance has been attributed to the low loss tangent (0.06–0.26), low real permittivity (11.3–23.9) F/m, median porosity (7.08 nm) and layered flower-shaped morphology of the material, all of which are desirable for the nonlinear saturable absorbance phenomenon.