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Characterization of magnetic biochar amended with silicon dioxide prepared at high temperature calcination

and increase the granules size, which further can be used in pollution control measures. In addition, the effect of calcination on textural, mineralogical, and magnetic properties of magnetic biochar amended with SiO 2 has seldom been studied in literature. In this study, magnetic kans grass biochar was amended with SiO 2 and calcined at 1000 °C under nitrogen environment to investigate the composite material textural, mineralogical, and magnetic variations using different characterization techniques (i.e. XRD, FT-IR, SEM, EDX, TGA, BET and saturation

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Synthesis and characterization of Ag@polycarbazole nanoparticles using different oxidants and their dispersion behavior

desirable to synthesize PCz based Ag nanocomposite to develop synergistic properties. Herein we used a strategy to adsorb Ag +1 and Fe +3 oxidants onto Ag NPs which were prepared by polyol reduction method to polymerize carbazole adhering to the surface of NPs[ 8 ]. The exploitation of Ag +1 and Fe +3 to polymerize carbazole around Ag NPs has been carried out to fabricate the composite materials. The morphology of the nanocomposite and polymer-metal phases was analyzed by TEM. The polymer was further characterized by FT-IR as PCz. Finally, surface plasmon resonance

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Synthesis and characterization of γ-glycine – a nonlinear optical single crystal for optoelectronic and photonic applications

numerous reports on this compound, the extraordinary characteristics of gamma glycine force the researches to perform deeper studies on its properties. The main aim of this work is to explore and shed light into anisotropic nature as well as the phase matching properties. Herein, we report the anisotropic behavior of gamma glycine in mechanical and laser damage threshold properties and the dependence of particle size with respect to second harmonic generation. Apart from these studies, single and powder X-ray diffraction analyses, UV-Vis spectroscopy, FT-IR analysis

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Synthesis and phosphorescent properties of the copolymers of N-vinylcarbazole, methyl methacrylate and iridium complex

Abstract

The copolymers containing carbazole unit and iridium complexes, such as (Ir(bpy)2Cl, Ir(mbpy)2Cl and Ir(Brbpy)2Cl, were synthesized via radical copolymerization of N-vinylcarbazole, methyl methacrylate and iridium complex. The synthesized copolymers were characterized by FT-IR, UV-Vis absorption spectroscopy and photoluminescence (PL) spectroscopy, respectively. According to the results, the copolymers (Ir(Brbpy)2Cl/PVK and Ir(mbpy)2Cl/PVK) exhibit yellow phosphorescence with an emission peak at around 553 nm under UV-visible light in the solid state. The results also reveal almost complete energy transfer from the host carbazole segments to the guest Ir complex in the copolymer film when the Ir content reaches 1.0 wt.%. The synthesized copolymers are good candidates as blue or yellow phosphorescent materials for PLED applications.

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Investigation on room temperature photoluminescence of pure and aluminum doped zinc oxide nanoparticles

Abstract

Pure and aluminum doped zinc oxide nanoparticles were prepared by soft chemical method. The prepared nanoparticles were characterized by XRD, SEM-EDAX, UV-Vis, PL and FT-IR studies. XRD patterns revealed that the nanoparticles were crystallized in hexagonal wurtzite structure with an average particle size of 19 nm to 26 nm. The surface morphology was explored using SEM micrographs. The incorporation of aluminum was confirmed by EDAX and FT-IR studies. The band gaps of the particles were found from 3.48 eV to 3.53 eV through UV-Vis spectral studies. The defect related mechanism was investigated using PL measurements. The chemical functional groups in FT-IR spectra proved the formation of pure and aluminum doped zinc oxide nanoparticles.

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Effect of fabrication technique on the crystalline phase and electrical properties of PVDF films

Abstract

The effect of different fabrication techniques on the formation of electroactive β-phase polyvinylidene fluoride (PVDF) has been investigated. Films with varying concentration of PVDF and solvent - dimethyl formamide (DMF) were synthesized by tape casting and solvent casting techniques. The piezoelectric β-phase as well as non polar β-phase were observed for both the tape cast and solvent cast films from X-ray diffraction (XRD) micrographs and Fourier transform infra-red spectroscopy (FT-IR) spectra. A maximum percentage (80 %) of β-phase was obtained from FT-IR analysis for a solvent cast PVDF film. The surface morphology of the PVDF films was analyzed by FESEM imaging. The dielectric properties as a function of temperature and frequency and the ferroelectric hysteresis loop as a function of voltage were measured. An enhancement in the value of the dielectric constant and polarization was obtained in solvent cast films.

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CdO-Fe3O4 nanocomposite with enhanced magnetic and photocatalytic properties

Abstract

Pure CdO nanopowder and CdO-Fe3O4 nanocomposite were synthesized by a cost effective chemical method, and the samples were characterized by XRD, SEM, TEM, FT-IR, UV-Vis-NIR and PL. Also, magnetic and photocatalytic properties of the synthesized samples were studied. XRD patterns of the composite confirm the presence of diffraction peaks related to both CdO and Fe3O4. EDX spectrum confirms the presence of the elements Cd, O and Fe in the composite. Peaks related to Cd–O and Fe–O bonds were observed respectively at 688 cm−1 and 592 cm−1 in the FT-IR spectrum. The paramagnetic behavior of pure CdO becomes ferromagnetic when coupled with Fe3O4. The composite exhibited a high photodegradation efficiency of 92.85 % against the degradation of methylene blue dye under visible light radiation.

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Evaluation of the acid properties of aluminossilicate MCM-22 material synthesized under static conditions

Abstract

The hydrothermal synthesis of MCM-22 zeolite was carried out using silica, sodium aluminate and hexamethyleneimine, under static conditions at 150 °C for a period of 10 days, followed by washing with deionized water, drying overnight and calcination at 650 °C. The obtained material was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The XRD analysis evidenced that MCM-22 presented a well defined MWW structure. The FT-IR spectrum confirmed the efficiency of the hexamethyleneimine as an organic template used to direct the structure of the MCM-22 zeolite under static conditions. The SEM image indicated that the particles are spherical in shape, with a diameter of ca. 10 μm. The acid properties of the MCM-22 zeolite, as determined by n-buthylamine adsorption, were investigated in the temperature ranges of 105 to 300 °C and 300 to 525 °C, relative to medium and strong acid sites, respectively.

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Synthesis and characterization of indium tin oxide nanoparticles via reflux method

Abstract

Synthesis of indium tin oxide (ITO) nanoparticles by reflux method without chlorine contamination at different pHs, temperatures, solvents and concentrations has been studied. Indium chloride, tin chloride, water, ethanol and Triton X-100 were used as starting materials. Structure, size, surface morphology and transparency of indium tin oxide nanoparticles were studied by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and UV-Vis spectrophotometry. XRD patterns showed that 400 °C is the lowest temperature for synthesis of ITO nanoparticles because metal hydroxide does not transform to metal oxide in lower temperature. FT-IR results showed the transformation of hydroxyl groups to oxide. SEM images showed that pH is the most important factor affecting the nanoparticles size. The smallest nanoparticles (40 nm) were obtained at pH = 8.8. The size of crystallites was decreased by lowering of concentration (0.025 M).

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Synthesis of maghemite (γ-Fe2O3) nanoparticles by thermal-decomposition of magnetite (Fe3O4) nanoparticles

Abstract

In this research work, we prepared γ-Fe2O3 nanoparticles by thermal-decomposition of Fe3O4. The Fe3O4 nanoparticles were synthesized via co-precipitation method at room temperature. This simple, soft and cheap method is suitable for preparation of iron oxide nanoparticles (γ-Fe2O3; Fe3O4). The samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), vibrating sample magnetometer and differential scanning calorimeter (DSC). The XRD and FT-IR results indicated the formation of γ-Fe2O3 and Fe3O4 nanoparticles. The TEM images showed that the γ-Fe2O3 and Fe3O4 were spherical, and their size was 18 and 22 nm respectively. Magnetic properties have been measured by VSM at room temperature. Hysteresis loops showed that the γ-Fe2O3 and Fe3O4 nanoparticles were super-paramagnetic.

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