Impact of Growth Temperature of Lead-Oxide Nanostructures on the Attenuation of Gamma Radiation.

Chemical bath deposition (CBD) technique is utilized to grow lead-oxide (PbO) nanostructures (NSs) over PbO seed fabricated by physical vapor deposition (PVD) method on glass substrates. The effect of growth temperatures 50 and 70 °C on the surface topography, optical properties, and crystal structure of lead-oxide NSs has been studied. The investigated results suggested that the growth temperature has a huge and very considerable influence on the PbO NS, and the fabricated PbO NS has been indexed as the Pb3O4 polycrystalline tetragonal phase. The crystal size for PbO thin films grown at 50 °C was 85.688 nm and increased to 96.61 nm once the growth temperature reached 70 °C. The fabricated PbO nanofilms show a high rate of transmittance, which are ∼70 and 75% in the visible spectrum for the films deposited at 50 and 70 °C, respectively. The obtained Eg was in the range of 2.099-2.288 eV. Also, the linear attenuation coefficient values of gamma-rays for shielding the Cs-137 radioactive source increased at 50 °C. The transmission factor, mean free path, and half-value layer are reduced at a higher attenuation coefficient of PbO grown at 50 °C. This study evaluates the relationship between synthesized lead-oxide NSs and the radiation energy attenuation of gamma-rays. This study provided a suitable, novel, and flexible protective shield of clothes or an apron made of lead or lead oxide to protect against ionizing radiation that meets safety rules and protects medical workers from ionizing radiation.

Sunlight harvesting for heat generation inside water using biosynthesized magnetite nanoparticles.

A low-cost, simple, inexpensive, and environmentally friendly method has been employed for synthesizing magnetite nanoparticles (Fe3O4 NPs). In this study, weeping willow (Salix babylonica L.) aqueous leaf extract has been utilized as a reducing, capping, and stabilizing agent. The synthesized Fe3O4 NPs were characterized by ultraviolet-visible (UV-Vis) spectroscopy, FT-IR spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), dynamic light scattering (DLS), zeta potential analysis, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The localized surface plasmon resonance (LSPR) performance of the Fe3O4 NPs was examined. It has been shown that the biosynthesized Fe3O4 NPs once dispersed in water can raise the temperature of water significantly when they absorb solar radiation through surface plasmon resonance (SPR). The impact of the pH value on the Fe3O4 NPs was also investigated. It has been shown that the optimum pH value among the examined pH values was pH 6. At this pH, the biosynthesized Fe3O4 NPs were able to increase the temperature of water from 25 °C to ∼36 °C. This dramatic increase in temperature was owing to the Fe3O4 NPs synthesized at pH 6 which acquired high crystallinity, monodispersity, high purity, minimum agglomeration, a small particle size, and high stability. In addition, the mechanism of converting solar energy to thermal energy has been discussed intensively. To the best of our knowledge, this study is unique and the novelty of this investigation is that Fe3O4 NPs acquire plasmonic-like properties under solar radiation. Also, they are anticipated to be an innovative photothermal adaptation material for solar-based water heating and heat absorption.

Fabrication and Characterization of High-Quality UV Photodetectors Based ZnO Nanorods Using Traditional and Modified Chemical Bath Deposition Methods.

Ultraviolet (UV) photodetectors (PDs) based on high-quality well-aligned ZnO nanorods (NRs) were fabricated using both modified and conventional chemical bath deposition (CBD) methods. The modified chemical bath deposition (M-CBD) method was made by adding air bubbles to the growth solution during the CBD process. The viability and effectiveness of M-CBD were examined by developing UV PDs based on ZnO NRs. The ZnO nano-seed layer was coated on a glass substrate utilizing radiofrequency (RF) sputtering. The impact of the different growth-times on morphology, growth rate, crystal structure, and optical and chemical properties were investigated systematically using different characterization techniques, such as field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) analysis, UV-VIS double beam spectrometer, and energy dispersive X-ray analysis (EDX), respectively. The Al/ZnO UV PDs based on ZnO nanorods were fabricated with optimum growth conditions through the two methods of preparation. This study showed that the synthesized ZnO NRs using the M-CBD method for different growth times possess better properties than the conventional method under similar deposition conditions. Despite having the highest aspect ratio and growth rate of ZnO NRs, which were found at 4 h growth duration for both methods, the aspect ratio of ZnO NRs using the M-CBD technique was comparatively higher than the conventional CBD method. Besides, the UV PDs fabricated by the M-CBD method at 5 V bias voltage showed high sensitivity, short response time, quick recovery time, high gain, low dark current, and high photocurrent compared with the UV PD device fabricated by the conventional CBD method.

Biosynthesis, Characterization and Mechanism of Formation of ZnO Nanoparticles Using Petroselinum Crispum Leaf Extract.

AIM: The study aimed at synthesizing ZnO NPs using Petroselinum crispum extract, commonly known as parsley, as a source of biosynthesis without utilizing chemical agents for reducing, capping and stabilizing agent. BACKGROUND: Recently, the biosynthesis of nanoparticles has been widely explored due to the wide range of vital applications in nanotechnology. Biosynthesized zinc oxide nanoparticles, ZnO NPs, have become increasingly important since they have many applications and are environmentally friendly. METHODS: The innovation of this investigation is that the nanosized ZnO NPs can be formed from one-pot reaction without utilizing any external stabilizing and reducing agent which is not plausible via the current procedures. RESULTS: The biosynthesized ZnO NPs were characterized using UV-Vis spectroscopy, FT-IR spectroscopy, X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Energy-dispersive X-ray spectroscopy (EDX) to investigate the optical, chemical, structural, and morphological properties. CONCLUSION: These techniques exhibited that the property of the biosynthesized ZnO NPs is analogous with the standard NPs prepared from dissimilar methods. Investigating the plausible mechanism of formation and stabilization of ZnO NPs by biomolecules of Petroselinum crispum leaf extract was another vital feature of this study.