Laser Science and Technology
Hajir M. Fadhil; Hyder A. Salih; Khaleel I. Hassoon
Abstract
In the present work, Laser Induced Breakdown Spectroscopy (LIBS) has been utilized to investigate two forms of aluminum samples, namely Al in the form of the nanoparticles (NPs) and a bulk (pellet). The Al target was irradiated by pulsed Nd-YAG laser with wavelength 1064 nm to produce plasma. The plasm ...
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In the present work, Laser Induced Breakdown Spectroscopy (LIBS) has been utilized to investigate two forms of aluminum samples, namely Al in the form of the nanoparticles (NPs) and a bulk (pellet). The Al target was irradiated by pulsed Nd-YAG laser with wavelength 1064 nm to produce plasma. The plasm spectrum is analyzed in the wavelength range between 250 nm and 700 nm. Some plasma parameters were calculated, including electron temperature (𝑇𝑒), plasma density (ne) and Debye length (𝜆𝐷) for different laser energies. The temperature of electrons was computed employing the Boltzmann plot technique, and the electrons density was computed utilizing the Stark broadening technique. This work aims to investigate the effect of laser energy on the plasma parameters and the influence of using two different forms of targets on these parameters. It was noted that increasing the laser energy from (400 mJ) to (700 mJ) resulted in an increase in electrons temperaturefrom (0.52 eV) to (0.65 eV) and an increase in electron density from (57.38×1016 cm-3) to (67×1016 cm-3) for the nano aluminum plasma, whereas the electrons temperature increased from (0.52 eV) to (0.59 eV) and the electron density increased from (43.88×1016 cm-3) to (55.05×1016 cm-3) for the bulk aluminum plasma.From the obtained results, it's concluded that using identical laser energies, the electron temperature and electron density of the plasma generated from aluminum in the form of nanoparticles are greater than that generated from aluminum in the bulk form. The differences in the calculated parameters for Al NPs and Al bulk belong to their different structures and morphologies as presented via Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD) methods.
Laser Science and Technology
Suha G. Ali; Mohammed S. Mohammed; Fatima I. Sultan
Abstract
The present work is a study of some properties of PbI2 deposited on porous silicon (n-PSi) by using the thermal evaporation technique. X-ray diffraction, scanning electron microscopy, UV–Vis spectrophotometer, and FTIR analysis were used to characterize the structural, optical, and morphological ...
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The present work is a study of some properties of PbI2 deposited on porous silicon (n-PSi) by using the thermal evaporation technique. X-ray diffraction, scanning electron microscopy, UV–Vis spectrophotometer, and FTIR analysis were used to characterize the structural, optical, and morphological properties of n-Psi. X-ray diffraction showed that the PbI2 film has a hexagonal polycrystalline structure, while FE-SEM images showed porous silicone in Photoelectrochemical etching, the pore distribution is irregular and the pore refers to the increased surface area of the silicon. SEM images of pbI2 film showed that particles were scattered and resembled gravel in size. The estimated optical energy value of thin films of PbI2 was 2.6 eV. PbI2 film has lower transmittance values at short wavelengths, but as the wavelength increases, the transmittance values gradually increased. The greatest transmittance value was 0.88. From FTIR analysis, chemical bonds were determined between porous silicon and PbI2.
Nanotechnology
Iman H. Hadi; Muslim F. Jawad; Khaleel I. Hassoon
Abstract
In this work, synthesis of titanium thin films on two different substrates (glass and n-type Si), with thicknesses of 90 and 145 nm at two different times (5 and 10 min) respectively, has been obtained. The thin films have been successfully deposited on glass and silicon substrates using DC diode sputtering ...
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In this work, synthesis of titanium thin films on two different substrates (glass and n-type Si), with thicknesses of 90 and 145 nm at two different times (5 and 10 min) respectively, has been obtained. The thin films have been successfully deposited on glass and silicon substrates using DC diode sputtering technique. The optical properties of the prepared thin films have been checked out using the optical reflectance spectrum. A significant reduction in surface reflectivity was observed at (10 min) sputtering time. The structural properties of the prepared thin films were studied using X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM). XRD results confirmed that titanium thin films had a hexagonal structure with preferred orientation on (002). The images of FESEM showed that all the samples had a uniform distribution of granular surface morphology. The grain sizes of the Ti nanostructure were estimated using Scherrers’ analysis. The thickness of Ti thin film increased as the sputtering time increased for both glass and Si n-type substrates. The repeated experiments revealed that most uniform Ti thin film is on Si substrate (n-type) with particle size 10 nm at deposition time 5 min.
Materials Science
Ghadeer Sadiq Jassim; Mojahid Najim; Wafaa Salih
Abstract
In this paper, a homogenous pure Barium Titanate with formula (BaTiO3) was prepared from pure Barium Carbonate (BaCO3) and titanium dioxide (TiO2) using the solid-state reaction technique, were used as raw materials having micro size by mixing of molar ratio [1:1], the powder was calcined at temperatures ...
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In this paper, a homogenous pure Barium Titanate with formula (BaTiO3) was prepared from pure Barium Carbonate (BaCO3) and titanium dioxide (TiO2) using the solid-state reaction technique, were used as raw materials having micro size by mixing of molar ratio [1:1], the powder was calcined at temperatures (900-1350) °C. The solid-State reaction can consider as an attractive process realistic alternative to the expensive wet-chemical route, according to X-ray diffraction, all of the peaks of Barium Titanate powder were perfectly suited to the positions of the peaks of the standard tetragonal phase in the pattern for this process. And with preferred crystalline size for the powder calcined at 1350 °C manifested the best results, where all the peaks indicate the formation of Barium Titanate completely. In addition, each BaTiO3 Nanopowder was compared to a micro powder that had been manufactured, by conducting x-ray diffraction, diffraction peaks undergo shifting toward higher angle to the high value of 2Ө, and Nano powder particles are smaller than micro powder particles. And this refers to a decrease in lattice parameters, in terms of the peaks of the Nano powder preceding the peaks of the micro powder of BaTiO3 and that match the result that is obtained by scanning electron microscopy (SEM).
