33 research outputs found
Formulation of Synthesized Zinc Oxide Nanopowder into Hybrid Beads for Dye Separation
The sol-gel prepared zinc oxide nanopowder was immobilized onto alginate-polyvinyl alcohol polymer blend to fabricate novel biocomposite beads. Various physicochemical characterization techniques have been utilized to identify the crystalline, morphological, and chemical structures of both the fabricated zinc oxide hybrid beads and their corresponding zinc oxide nanopowder. The thermal stability investigations demonstrate that ZnO nanopowder stability dramatically decreased with its immobilization into the polymeric alginate and PVA matrix. The formulated beads had very strong mechanical strength and they are difficult to be broken up to 1500 rpm. Moreover, these hybrid beads are chemically stable at the acidic media (pH < 7) especially within the pH range of 2–7. Finally, the applicability of the formulated ZnO hybrid beads for C.I. basic blue 41 (BB41) decolorization from aqueous solution was examined
Utilization of Synthesized Nano-Zinc Oxide in Yellow Basic Dye Decontamination from Industrial Wastewater
ZnO nanorod has been successfully synthesized through the reduction of Zinc chloride salt with ammonia solution in the presence of triethanolamine (TEA) as surfactant agent via hydrothermal technique. The properties of the produced material were determined using different characterization techniques such as X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and Fourier Transform Infrared spectrum (FTIR). The results showed that the asprepared ZnO are rod- like morphologies at pH equal to 10. The synthesized nano rod-zinc oxide was employed asadsorbent agent for basic yellow 28 dye decolorization from polluted industrial wastewater. The synthesized nano-ZnO was achieved 93.26% dye decolorization affinity with in 60minutes. The variation in the different processing parameters on the dye sorption process was elucidated using batch technique. The increment in both the dye solution pH and its temperature was association with decline in the decolourization process. The optimum nano-zinc oxide dosage was recorded to be equal to 10 g/L. The adsorption data at equilibrium were analyzed using Langmuir, Freundlich and Temkin equilibrium isotherms. The experimental results confirmed the applicability of synthesized nano-zinc oxide as adsorbent agent for dye decontamination from polluted wastewater.Keywords: nano-zinc oxide, dye decolourization, sorption parameters
Influence of Reaction Time, Reducing Agent and Zinc Precursors on the Morphological Structures of Zinc Oxide
ZnO either nanoparticles or nanorods were synthesized via sol-gel technique. Many factors were studied and optimized in order to obtain different morphological structures of nano-ZnO. Effect of reaction time (3, 6, 12, 24 and 48 hours) has been studied to optimize the best preparation condition. Reducing agent (NH3, NaOH and KOH) is one of the factors affect on morphological structures, which has been studied in this work. Other effect has been studied in this work is zinc precursors such as Zn(NO3)2, ZnAc2, ZnCl2, and ZnBr2. The morphological structures of prepared ZnO were revealed using scanning electron microscope (SEM) and the aspect ratios were calculated. x-ray diffraction (XRD) patternsexposed a highly crystallized wurtzite structure and used for identifying phase structure and chemical state of ZnO under different preparation conditions.Keywords: sol-gel, morphological structures, reducing agent, SEM, preparation conditions
Basic Violet Decolourization Using Alginate Immobilized Nanozirconium Tungestovanadate Matrix as Cation Exchanger
As an innovative cation exchange material, nanozirconium tungestovanadate prepared using homogeneous precipitation technique was immobilized into alginate matrix and evaluated for cationic dye decolourization. Physicochemical properties of the prepared composite material were examined to determine its crystallinity, morphology, and ion exchange capacity. The SEM and TEM images of the prepared zirconium tungestovanadate identified that it was prepared in homogeneous structure with spherical shape in average diameter 22 nm. However, the optical microscope image of the composite matrix confirms the good distribution of nanozirconium tungestovanadate into the polymeric matrix. Batch technique was utilized to test the cation exchange efficiency of the prepared composite material toward C.I. basic violet 16 dye decolourization. The optimum immobilized dosage from nanozirconium tungestovanadate into the polymeric matrix to achieve 99% dye decolourization from 50 ppm initial dye concentration was recorded as 8 g/L. The dye sorption process onto the prepared material is described as an endothermic process. The dye sorption process at equilibrium was following both Langmuir and Freundlich isotherm models. The kinetic sorption behaviour of dye onto the composite matrix is correlated to pseudo-second-order equation model
Fabrication of ZnO and ZnO:Sb Nanoparticles for Gas Sensor Applications
ZnO and Sb-doped ZnO nanoparticles were successfully prepared using sol-gel technique. Different concentrations of triethanolamine (TEA) were utilized as the preparation procedure to act as complexing agent that enhances the doping probability of the formed Sb-doped ZnO nanopowder. Thick films of the prepared nanopowders were fabricated with spinner coating. Morphological characteristics, phase structure, chemical composition, thermal stability, and optical properties of the prepared nanopowders were measured and analyzed. The average crystallite size of ZnO and ZnO:Sb powders ranged between 19–28 nm according to the XRD calculations and TEM observations. The gas sensitivity of the homemade devices based on Sb-doped ZnO nanoparticles towards O2 and CO2 gases as a function of temperature was measured and compared with undoped ZnO films. The gas sensitivity of the films was greatly improved after doping with Sb and reached its maximum value of ~86% for O2 gas at 93:7 wt% of Zn:Sb
Influence of Reaction Time, Reducing Agent and Zinc Precursors on the Morphological Structures of Zinc Oxide
ZnO either nanoparticles or nanorods were synthesized via sol-gel technique. Many factors were studied and optimized in order to obtain different morphological structures of nano-ZnO. Effect of reaction time (3, 6, 12, 24 and 48 hours) has been studied to optimize the best preparation condition. Reducing agent (NH3, NaOH and KOH) is one of the factors affect on morphological structures, which has been studied in this work. Other effect has been studied in this work is zinc precursors such as Zn (NO3)2, ZnAc2, ZnCl2, and ZnBr2. The morphological structures of prepared ZnO were revealed using scanning electron microscope (SEM) and the aspect ratios were calculated. x-ray diffraction (XRD) patterns exposed a highly crystallized wurtzite structure and used for identifying phase structure and chemical state of ZnO under different preparation conditions
Utilization of Synthesized Nano-Zinc Oxide in Yellow Basic Dye Decontamination from Industrial Wastewater
ZnO nanorod has been successfully synthesized through the reduction of Zinc chloride salt with ammonia solution in the presence of triethanolamine (TEA) as surfactant agent via hydrothermal technique. The properties of the produced material were determined using different characterization techniques such as X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and Fourier Transform Infrared spectrum (FTIR). The results showed that the as prepared ZnO are rod- like morphologies at pH equal to 10. The synthesized nano rod-zinc oxide was employed as adsorbent agent for basic yellow 28 dye decolorization from polluted industrial wastewater. The synthesized nano-ZnO was achieved 93.26% dye decolorization affinity with in 60minutes. The variation in the different processing parameters on the dye sorption process was elucidated using batch technique. The increment in both the dye solution pH and its temperature was association with decline in the decolorization process. The optimum nano-zinc oxide dosage was recorded to be equal to 10 g/L. The adsorption data at equilibrium were analyzed using Langmuir, Freundlich and Temkin equilibrium isotherms. The experimental results confirmed the applicability of synthesized nano-zinc oxide as adsorbent agent for dye decontamination from polluted wastewater
Structural and Optical Properties of Varies Thickness of Znte Nanoparticle
ZnTe thin films of different thicknesses were deposited onto glass substrates for optical devices applications. Xray diffractogram of different thicknesses for ZnTe films are measured and their patterns exhibits polycrystalline nature with a preferential orientation along the (111) plane. X-ray diffraction techniques have been employed to determine themicrostructure parameters, both crystallite size and microstrain. Film thickness and the optical constants of ZnTe films were calculated based on the measured transmittance spectral data using Swanepole’s method in the wavelength range 400–2500 nm. The refractive index n and absorption index k were calculated and the refractive index exhibits a normal dispersion. The refractive index could be extrapolated by Cauchy dispersion relationship over the whole spectra range, which extended from 400 to 2500 nm. The optical band gap can be calculated in strong absorption region and displays an allowed direct transition. Both the refractive index and the band gap increase with the increase film thickness, thus ZnTe/glass substrates are good candidates in optoelectronic devices.Keywords: ZnTe, thin film, cry crystallitze size; microstrain; optical constants
Structural and Optical Properties of Varies Thickness of Znte Nanoparticle
ZnTe thin films of different thicknesses were deposited onto glass substrates for optical devices applications. Xray diffractogram of different thicknesses for ZnTe films are measured and their patterns exhibits polycrystalline nature with a preferential orientation along the (111) plane. X-ray diffraction techniques have been employed to determine the microstructure parameters, both crystallite size and microstrain. Film thickness and the optical constants of ZnTe films were calculated based on the measured transmittance spectral data using Swanepole’s method in the wavelength range 400–2500 nm. The refractive index n and absorption index k were calculated, and the refractive index exhibits a normal dispersion. The refractive index could be extrapolated by Cauchy dispersion relationship over the whole spectra range, which extended from 400 to 2500 nm. The optical band gap can be calculated in strong absorption region and displays an allowed direct transition. Both the refractive index and the band gap increase with the increase film thickness, thus ZnTe/glass substrates are good candidates in optoelectronic devices