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In recent years, vanadium pentoxide (V2O5) nanoparticles (NPs) have attracted considerable interest due to their potential medicinal applications, including cancer therapy, antibiotic resistance and antibacterial activity. Manufacturing V2O5 NPs is a crucial step in developing these applications, and laser ablation in solution has proven to be a particularly successful technique. Following fabrication, colloidal solutions were analyzed using ultraviolet–visible (UV–Vis) absorption spectra, Fourier transform infrared (FTIR) spectrum, transmission electron microscopy (TEM) and X-ray diffraction (XRD). In this work, XRD study revealed that the produced NPs had an orthorhombic phase. Based on the laser energy, nanosized vanadium pentoxide particles were created by laser irradiating a vanadium bulk submerged in a double deionized water (DDW), resulting in spherical particles with average sizes ranging from 15.4 to 33.8 nm, as shown by TEM micrographs. Conforming to the quantum size concept, the bandgap energy of V2O5 NPs is higher than that of bulk V2O5 due to the decrease in particle size. This study examined the effectiveness of V2O5 NPs against pathogenic bacterial strains Staphylococcus aureus as Gram's positive bacteria and Escherichia coli as negative Gram's bacteria. Then, we evaluated anticancer activity of V2O5 NPs against a breast cancer cell line (MCF-7 cells) using MTT assay. The results reveal that the activity of prepared V2O5 NPs against S. aureus is greater than that of E. coli. The findings suggest that prepared NPs can act as an anti-proliferative agent against MCF-7 cells. Subsequently, the produced NPs might be exploited as a future strategy for other biomedical applications. [ABSTRACT FROM AUTHOR]

In this study, we used the pulsed laser ablation (PLA) method to make Au:MgO nanoparticles on porous silicon (PS) substrates. The optical characteristics, crystallinity and surface morphology of generated Au:MgO nanoparticles have been investigated with utilizing XRD, TEM, AFM, UV–Vis, PL and fabrication of gas sensors examined at various laser energies. Au:MgO nanoparticles have been manufactured by pulsed laser ablation method (Q-switched) fundamental 1064-nm Nd:YAG, at different laser energies 600, 800 and 1000 mJ and 100 shots, and then sedimentation on surface of PS (porous silicon) layer prepared by photoelectrochemical etching method. The properties of samples are analyzed by XRD (X-ray diffraction), AFM (atomic force microscope) and TEM (transmission electron microscope). The prepared samples were spherical nanoparticles with an average of roughness and diameter 13.4 and 36.76 nm. The production of approximately spherical core- shell of Au:MgO NPs is indicated by TEM with a mean particle size of 10–55 nm. Also the face cubic-centered shape of Au:MgO NPs is revealed by XRD. Eventually, the diversity of running temperature on the sensor sensitivity, recovery times and the time of response for NO2 and H2S gas sensors fabricated from prepared specimens was studied. The maximal sensitivity of Au:MgO NPs/PS excised by laser energy of 800 mJ of NO2 gas was evaluated as 41.1%, while the maximal sensitivity of Au:MgO NPs/PS excised with a pulsed laser of 1000 mJ of H2S gas is much greater compared to NO2 gas. [ABSTRACT FROM AUTHOR]

In the present work, we used a pulsed laser deposition technique to embed TiO2 nanostructure on porous silicon substrates using a pulsed laser deposition process. Nanocrystalline porous silicon was synthesized using the photo-assisted electrochemical method. The study analyzed the optoelectronic characteristics of double junctions of TiO2/PS/n-Si structures as well as the PS/n-Si structure. We investigated the properties of TiO2/PS/n-Si and PS/n-Si structures, focusing on their structural, optical, and electrical features under ambient conditions. The XRD measurement indicated the formation of the anatase and rutile tetragonal phases with the preferred orientation anatase (101) plane in the prepared sample. The mean sizes of The TiO2 nanostructures deposited onto porous silicon substrates range from 45.97 to 109.23 nm. The degree of pore filling depends upon the laser fluences employed, varying from moderate to close to complete packing. The optical properties of TiO2/PS/n-Si structures showed decreasing reflectance after depositing on porous silicon. The TiO2 nanostructure produced on porous silicon exhibits five different spectra in the UV and visible range, as displayed in the room-temperature photoluminescence analysis. The current density–voltage characteristics of formed samples in dark and photoilluminated conditions are examined at room temperature. The properties of the TiO2/PS/n-Si structure enhance those of the PS/n-Si device. The highest specific detectivity of the TiO2/PS/n-Si devices is 32.45 × 1010 Jones in the visible region, while the ultraviolet region is 30.04 × 1010 Jones. The TiO2/PS/n-Si photodetectors possess an optimal relative quantum efficiency of 80.1% in the near UV region, whereas, in the visible range, the values of relative quantum efficiency are 51.8% at 531 nm and 54.5% at 634 nm. The findings reveal that formed photodetectors exhibit UV and visible light sensitivity after depositing TiO2 layers on porous silicon. However, the photodetectors produced using TiO2 nanostructures placed on porous silicon demonstrate greater sensitivity than those made from as-synthesized porous silicon. [ABSTRACT FROM AUTHOR]

In this study, the properties of the porous silicon (PS) photodetector were improved by depositing Au@In2O3 (core-shell) nanoparticles on the surface of PS. The Au@In2O3 NPs were prepared using the pulsed laser ablation in liquid (PLAL) technique at different laser energies of 500, 700, and 900 mJ, using a Nd:YAG laser with a wavelength of 1064 nm. The PS was prepared using the electrochemical etching (ECE) method, with an etching current density of 20 mA/cm2, an etching time of 15 min, and a hydrofluoric acid concentration of 25%. Structural, morphological, optical, and electrical measurements of the PS, Au@In2O3 NPs, and Au@In2O3 NPs/PS were conducted using the X-ray diffraction (XRD) test, field-emission scanning electron microscopy (FE-SEM) analysis, photoluminescence (PL), and UV-vis spectroscopy showed the highest peak of absorbance at 327–385 nm, and the photoluminescence (PL) peak of Au@In2O3 NPs was in the visible range show broad band and splitting for 399.5 nm for In2O3 NPs and 469 nm for Au NPs, while the PS peak was at about 561.8 nm. As a result, the photodetectors device system exhibited high responsivity (Rλ) and quantum efficiency in the visible area, the higher responsivity of the Au@In2O3 NPs/PS photodetector was measured as 0.1450 A/W for specimens prepared at a laser energy of 500 mJ/pulse. [ABSTRACT FROM AUTHOR]

The purpose of this study is to explore if nanostructured Au–TiO2 particles can replace traditional, bulkier materials in gas sensing applications. Then use a Nd-YAG laser with a wavelength of 1064 nm, number of shot 500 pulse, and 500 mJ, 660 mJ, and 820 mJ laser ablated energy, the pulsed laser deposition technique has been widely used to prepare and characterize Au–TiO2 nanoparticles on Porous Silicon substrate produced on n-type Silicon wafer. By using of drop casting method, the Au–TiO2 NPs have deposited on porous silicon (PS) layer with 15 drops of each specimen. The morphology of PS layer, Au:TiO2 NPs and Au–TiO2 NPs/PS specimens were reviewed using scanning electron microscopy, XRD pattern analysis, and transmission electron microscopy. We found that the Au:TiO2 NPs play important role to develop electrical properties and sensitivity to H2S and NO2. [ABSTRACT FROM AUTHOR]