Papers by Keyword: Laser Ablation

Abstract: Pulsed laser ablation in liquid (PLAL) is considered a relatively fast, simple to manipulate, cost-effective abraoch, and enables the fabrecation of multiscale micro-nanostructures in one step, facilitating the fabrication process. Copper nanoparticles solution was prepared by PLAL technique using Nd:YAG laser in deionized water at (532 nm), (1000 pulse), and the energies (700 mJ, 800 mJ, 900 mJ, and 1000 mJ) with a fixed distance between the laser source and the sample, fixed amount of liquid, and the liquid rise above the copper was (5 mm). The effect of the excess of the laser energy in the preparation process was tested by analyzing the optical properties of the fabrecated samples by UV-Visible spectrophotometer, SEM, XRD, and EDX measurements.

Abstract: Nanoparticles fabrication using pulsed laser synthesis is considered a straightforward, reliable, and green approach for the fabrication of nanomaterials. In this study, cobalt oxide (CoO) nanoparticles were synthesized from cobalt targets using pulsed laser ablation inside a 10% v/v ethanol solution. This study examined the effect of the laser energies on the size and morphology of CoO nanoparticles. The size, morphology of the fabricated nanomaterials were studied using transmission electron microscopy (TEM), and their optical properties were obtained using ultraviolet-visible (UV-Vis) spectroscopy. Uniform size distribution of nanoparticles with diameters less than 60 nm was observed at 30, 45, and 60 mJ. The optimum condition at which the CoO nanoparticles are fabricated with a narrower size distribution was reported, which would be helpful in several applications such as electronic thin film, pigments and dyes, capacitors, gas sensors, and lithium-ion batteries.

Abstract: The article is devoted to the method of obtaining a diamond-like coating on a silicon substrate by laser ablation of a glassy carbon target in a vacuum. The presented technology makes it possible to achieve the synthesis of wear-resistant thin-film coatings with a thickness of about 200 nm. The diagnostics of the obtained coating was carried out using probe microscopy, the chemical and phase composition was estimated by the Raman spectra.

Abstract: Zinc, nickel and silver oxide were prepared by the method of pulsed ablation laser in liquid, with different preparation conditions, where the number of pulses was changed (25, 50 and 75) and the frequency was 1 Hz and the energy was 600 mJ and at room temperature. We have used UV-visible spectroscopy, field emission scanning electron microscopy (FSEM), the EDX system, then these materials were added to the local dye and the photo-catalytic activity was applied to them using a UV-500 lamp for different periods of time (0, 30, 60 and 120 mint) and they acted as photo-catalysts.

Abstract: Abstrac. In the present work, gold nanoparticle (Au NPs) was synthesis by pulsed laser ablation (PLA) by using Q-switched, (Nd: YAG) (E=80mJ) (λ=532,1064nm) and Number of pulses (500)pulse of the gold metal target in deionized water. The optical properties were studied with a UV-vis spectrophotometer which tests the absorbance spectra and comparison of the generated nanoparticles solution. atomic force microscope (AFM) results show that the grain size increase by decreasing wavelength. The optical limiter of the resulting colloidal solution was studied.

Abstract: In this study, one hundred ten male white rabbits of the New Zealand type, weight (1-2) Kgm, age (12-18) month, obtained from local markets, rabbits was putted in specific cages specially made for this purpose one week before dosing, and under appropriate conditions of temperature (25-28) °C, a light period (14) hour per day. With good ventilation, the standard bush and water were provided to rabbits using aluminum containers in equal quantities. Rabbits were orally administered for two weeks with CdS nanoparticles (dose= 1ml/kg and concentration=20 μg/mL orally), after which blood was drawn from the rabbit's heart to make blood measurements and liver enzymes. Rabbits were dissected and liver was preserved with formalin for histological examination. Keywords: CdS Nanoparticles; Laser Ablation; Neuronal toxicity; Liver; Beta vulgaris L..

Abstract: Abstract. Laser ablation of a silver target immersed in distilled water utilizing Nd: YAG laser with wavelengths of 532nm,1064nm, and 1320nm was carried out to fabricate silver nanoparticles. The synthesis of Ag NPs was carried out using various laser energy (200-1000 mJ) and different pulses (200-1000 pulse). Optical properties for the Ag nanoparticles solution were tested using UV-Visible spectrum, while the morphological properties for the Ag-nanoparticles solution after deposited on glass were tested using the atomic force microscope (AFM). The results showed that the synthesis of the Ag-nanoparticles using pulsed laser ablation in liquid (PLAL) (water) gives nanoparticles with homogeneous grain distribution and uniform surface roughness. It was found that the absorption peaks of Ag NPs increase by increasing the number of pulses shoot for the same laser wavelength and laser energy, and the reported maximum value of absorption peak is 0.363 when using 1000 pulses shoot. AFM results showed that the average diameter of the Ag NPs prepared by PLAL increases with increasing the laser wavelength. However, when using laser wavelengths of 1320nm,1064nm, and 532nm, the resulted average diameter of silver nanoparticles will be 55.38nm, 34.18nm, and 30.3nm, respectively. Finally, the average surface roughness of the Ag NPs prepared by PLAL increased with increasing the laser wavelength. The obtained average surface roughness of silver nanoparticles when using wavelengths of 1320nm,1064nm, and 532nm were 2.75nm, 1.19nm, and1.06nm, respectively.

Abstract: The article discusses the possibility of using pulsed laser ablation of nanosecond duration to modify the surface of a cutting tool after regrinding and restoration. Experimental studies of the resistance characteristics of cutting tools with modified surfaces via laser ablation in air and in liquid have been carried out. It was found that after modifying the surface of cutting plates via laser ablation in air, the wear on the trailing surface of the cutting tool at a processing speed of V = 50 m/min is 8 times less than that of the untreated one, the build-up is 20 times less. The wear of the trailing surface of the plates at V = 70 m/min is 2 times less than that of the untreated sample. The resistance studies show surface modification of the cutting tool increases the tool life of the remanufactured tool, overall tool life and savings in tool costs.

Abstract: In this research optical properties of synthesized gold-graphene/polyvinyl alcohol (AuG/PVA) nanocomposite have been investigated. Gold and graphene nano colloidal solution (NCS) synthesized by laser ablation method individually. The resulting NCS were characterized by UV-Vis absorption spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). PVA/Au and PVA/AuG with different concentration of AuG were mixed to form polymeric films via solution casting. Doped polymeric films were analyzed by FTIR and spectrophotometer analyses. The results show that by increasing of AuG concentration, the band gap energy of the PVA films significantly enhanced and other optical parameters such as refraction and extinction coefficients remarkably changed.

Abstract: We prepared Zinc oxide nanomaterial employing PLA (pulsed laser ablation) technique. A pure Zn target was immersed in ultra-pure water (UPW) and it was subjected to several pulses (1st. and 2nd. harmonic) of the pumping Nd: YAG laser. The influence of changing laser’s wavelength (1064, 532) nm on the characterization of the produced nanoparticles was studied. The results obtained from studying the structure, topography, and morphology of the product showed that the particles have a hexagonal shape. Also, changing the wavelength of the laser from 532nm to 1064nm leads to size reduction and density increasing of the nanoparticles.