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In this study, palladium (Pd) nanoparticles were prepared using a laser ablation method and investigated using XRD, transmission electron microscopy (TEM), microscopic atomic force (AFM), UV-vis, PL, and various We investigated the fabrication of gas sensors with laser energy, Pd nanoparticles were generated by laser ablation in liquid applying a magnetic field with a pulse energy of 660 mJ for 200 shots, and Pd NPs were precipitated onto porous silicon (PS) using a drop casting process. The specimen's nanocrystalline had been revealed by the XRD diffraction pattern. AFM demonstrated a growth in the agglomeration of Pd NPs; the TEM results indicated that the average particle size of Pd particles between 52.44 and 16.07 nm is decreased in presence of magnetic field. Photoluminescence detector electronic properties of energy band gap described increases from 3.16 to 3.44 eV. The sensor sensitivity for NO2 and H2S gas sensors constructed from the prepared material were also examined in relation to temperature changes. For Pd NPs/PS/Si, gas sensors have a maximum sensitivity of around 75.6% at 100 ◦C for sample prepare 660 mJ without magnetic field, but the highest sensitivity in the presence of a magnetic field was 28.72% at 25 ◦C for H2S gas. Additionally, it can achieve maximum sensitivity of Pd NPs/PS/Si at gas sensor to 63.09% and 55.66% in both the presence and absence of a magnetic field for NO2 gas, respectively. Effect of temperature change on reaction time and sensor sensitivity [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]

Ag:Au nanoparticles are prepared and studied in the form of pure, stable, highly concentrated, and non-toxic core–shell; the method of preparation was the seed growth method which involves preparation of silver seeds and is done via a chemical reaction between AgNO3, Na3C6H5O7, and NaBH4 to produce them; the next step was done by another chemical reduction of C6H8O6 and HAuC14 in a CTAB solution in different quantities (0.4 ml, 0.6 ml, 0.8 ml, and 1 ml). The morphology study revealed that the Ag:Au (core–shell) NPs deposited on porous silicon (PS) exhibited strong adhesion, leading improved structural stability of the PS substrate. Analysis of the UV–Vis spectra of NPs showed a localized surface plasmon resonance (LSPR) band within the spectral range of (420 to 540) nm wavelength. As the amount of gold Au NPs increased, the LSPR band transitioned from two peaks to almost one. In this work, the Ag:Au (core–shell) NPs are manufactured by seed growth method these nanoparticles are deposited on porous silicon (PS). Photoluminescence spectra, X-ray, TEM, UV–vis, and Raman were found. This research will provide some guidance to the developers of the n-type based Ag:Au (core–shell) NPs/PS sensor. [ABSTRACT FROM AUTHOR]

This study investigates the impact of laser pulse energy (500 mJ/pulse) on silver, gold, and silver@gold NPs and deposited on porous silicon. The objective is to assess their effects on structural, optical, morphological, and electrical properties, aiming to identify optimal conditions. Nanoparticles are produced through the technique of pulsed laser ablation in liquid (PLAL). This involves employing a Q-switched Nd: YAG laser operating at a wavelength of 1064 nm and pulse duration of 10 ns. X-ray diffraction (XRD) analysis validates the crystalline development of (core–shell) NPs, evident from the presence of XRD peaks corresponding to Au and Ag NPs. Morphological analysis reveals excellent adhesion between NPs and the substrate (PS), enhancing structural stability. UV–vis spectra demonstrate a localized surface plasmon resonance (LSPR) band within the 420–540 nm range. This band shifts from two peaks to one with increased gold content. A comparison of the photoluminescence emission spectra of porous silicon and Ag@Au NPS/PS at room temperature. The porous silicon exhibits an extreme PL emission band broadening centered at a visible wavelength of 620 nm (2.033 eV), which reveals the excellent quality of the PS structure. Photodetector measurements highlight maximum responsivity for the Ag@Au/PS photodetector. These Ag@Au NPs show promising attributes for high-performance photodetector applications. [ABSTRACT FROM AUTHOR]

In this study, a simple method for creating palladium nanoparticles (Pd NPs) using laser ablation in a liquid medium at a wavelength of 1064 nm at different laser energies, 360, 660, and 800 mJ by 200 pulses, was investigated. The aim was to determine the differences in the structural and physical characteristics of the samples and examine the resulting changes. The presence of palladium nanoparticles was demonstrated through X-ray diffraction, and the crystal sizes were found to be 49.9, 41.5, and 16.8 nm for laser energies of 360, 660, and 800 mJ, respectively. Morphology was investigated by analyzing TEM, and the average particle sizes, as indicated by the histogram, were 100, 83.6, and 45.3 nm. Optical characteristics were assessed using UV-Vis and photoluminescence. There was an increase in the energy gap values of 2.53, 2.62, and 2.65 eV with increasing laser energy of 330, 600, and 800 mJ, respectively. The photocatalytic activity of Pd NPs in the color reduction of methylene blue (MB) was evaluated using a UV-Vis spectrophotometer to assess the utilization of samples in photocatalysts and the strength of the impact of the nano-solution on the dye. These results showed that Pd NPs exhibit significant catalytic activity in the reduction of methylene blue, especially at an energy of 800 mJ, the percentage of dye analysis reached 85% within 50 min. [ABSTRACT FROM AUTHOR]

In this study deposited zinc oxide (ZnO) nanostructures were prepared by pulsed laser deposition (PLD) technique on porous silicon (PS) substrates that were prepared via photoelectrochemical etching of silicon n-type (100). The study investigated the influence of laser energy on various characteristics of the fabricated devices, including their optical, morphological, structural, electrical, and photodetector features. The X-ray diffraction results indicate a dominant broad diffraction peak at 69.14°, and the ZnO phase aligns with the hexagonal wurtzite structure. The field emission scanning electron microscopy micrograph illustrates that porous silicon has a sponge-like fashion, while ZnO nanostructures have spherical grains distributed randomly and grow larger with laser energy. The optical characteristics of the manufactured samples were examined using techniques that include UV–vis absorption spectroscopy, UV–vis diffuse reflectance spectrometry, and photoluminescence spectroscopy. The findings indicated that decreased laser energy led to a blue shift in the energy gap. The reflectivity of the produced samples decreased after the deposition of a zinc oxide layer over porous silicon. The photoluminescence examination showed the presence of four distinct emission peaks, namely, UV, violet-blue, blue, and green, consequent to coating a ZnO layer onto the porous silicon substrate. Fourier transform infrared spectroscopy confirmed that ZnO thin films deposited on porous silicon cause surface oxidation and produced a new peak at 455.2 cm−1 related to the Zn–O stretching band. The current density–voltage properties of the fabricated devices in the absence and presence of white light were investigated as a function of laser energy. The ZnO NPs/PS/n-Si photoreactors displayed rectifier features and had outstanding spectral responsivity from ultraviolet to near-infrared. Moreover, the fabricated photoreactor showed the most prominent external quantum efficiency (EQE) in the UV region. The results of this study are of great importance to the advancement of photodetectors and optoelectronic devices based on ZnO and porous silicon. [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]

The combination of common semiconductors with porous materials has the potential to augment the splitting of electrons and holes, hence increasing the efficiency of photodetectors. In the current study, we present the efficient fabrication of photodetectors consisting of vanadium pentoxide (V2O5) and macroporous structures via the pulsed laser deposition technique. The structure, surface morphology, and optical properties of V2O5 nanostructures embedded in porous silicon were examined using an X-ray diffractometer, a field emission scanning electron microscope, and a UV–Vis–NIR diffuse reflectance spectrophotometer, photoluminescence emission spectra, and Fourier transformation infrared spectroscopy. The findings indicate that the V2O5 nanostructure exhibits an orthorhombic crystal structure, which tends to align along the (001) plane. These nanostructures were distributed on porous silicon surfaces, mainly within the pores, which range in size from 52.4 nm to 106.5 nm. The level of pore filling varies depending on the laser energy used, ranging from partial to almost complete filling. The room-temperature photoluminescence peaks of V2O5 nanostructure/porous silicon possess four distinct spectra characterized by their maximum emission wavelengths of around 461 nm and 664 nm.However, the electrical and spectral responsivity properties were measured before and after introducing V2O5 nanostructures into porous silicon. The ideality factor of porous silicon has decreased after embedding V2O5 nanostructure in porous silicon. The deposition of V2O5 nanostructures into porous silicon resulted in a significant rise in spectrum responsivity, particularly at a wavelength of 471 nm. Moreover, the spectral responsivity exhibited a rising trend with increasing laser energy, reaching a maximum value of 0.31 A/W. The external quantum efficiency found its highest value at 78.93% when more incredible laser energy was used. The V2O5 nanostructure/porous silicon device fabricated in this work, consisting of a V2O5 nanostructure integrated with porous silicon, has remarkable potential as a high-efficiency photodetector in several photoelectronic technologies. [ABSTRACT FROM AUTHOR]

In this work, the synthesis and characterization of gold nanoparticles (Au NPs) were performed by pulsed laser ablation in liquid (PLAL) technique at different laser energies (500, 700, and 900 mJ) using Nd:YAG laser Q-switching wavelengths (1064 nm) and then deposited on porous silicon (PS). The PS was prepared using the electrochemical etching (ECE) method at an etching current density of 20 mA/cm2, an etching time of 15 min, and a hydrofluoric acid concentration of 25%.The structural, morphological, and optical properties of PS, Au NPs, and Au NPs/PS were determined using X-ray diffraction tests, FE-SEM analysis, UV–Vis spectroscopy, and photoluminescence (PL), respectively. The electrical characteristics of Al/Au NPs/PS/Si/Al heterojunctions have been determined with measurements of current–voltage (I-V) in the dark and under illumination. From the photo-detector measurements, the spectral responsivity curves included three regions; the first peak was due to absorption of the visible light by Au NPs. The second peak corresponds to the absorption of near-infrared light by the PS layer, and the third peak corresponds to the absorption edge of the Si substrate. The higher responsivity of the Au NPs/PS photo-detector was found to be 0.23 A/W for specimens prepared at laser energy of 500 mJ. [ABSTRACT FROM AUTHOR]

In the present paper, preparation and characterization of Palladium (Pd) NPs with laser ablation, from palladium target in die-ionize water at various values of laser pulse energy 360, 660 and 800 mJ with 200 shots via 532 nm laser wave-length. Prepared porous silicon (PS) layers from n-type with orientation (100) through the PECE (i.e. photo-electrochemical etching) approach. Morphological synthesis of Pd NPs with deposited upon PS enlarge perfect cohesion between those nano-structures major to get better structural stabilization of the layer of PS. X-ray diffraction (XRD), Field Emission Electron microscopy (FE-SEM), Transmutation Electron microscopy (TEM), UV–vis spectroscopy, electrical characteristics (J-V) and Photo-detector are deployed to describe the products. The Pd NPs/PS detector measurements have shown higher level of the responsivity 24.6A/W at 660 mJ. [ABSTRACT FROM AUTHOR]

Zinc oxide nanoparticles (ZnO NPs) were formed in the present paper, employing a pulsed laser irradiation approach on a pure zinc target surrounding double deionized water. The structure, morphology, chemical bonding, and optical characteristics of prepared ZnO nanoparticles were investigated using X-ray diffraction, transmission electron microscopy, spectrophotometer, and Fourier-transform infrared spectroscopy. The nanoparticles have a nanocrystalline structure with a hexagonal wurtzite arrangement and are spherical with diameters ranging from 5 to 60 nm depending on the laser energy. The analysis of ultraviolet–visible spectroscopy shows a blue shift with decreasing laser energy, and the optical energy bandgap increases as particle size decreases. The FTIR spectrum of ZnO nanoparticles identified at 512.37 cm−1 and 448.63 cm−1 was ascribed to Zn–O-Zn stretching vibrations. However, using the agar well diffusion technique, ZnO nanoparticles were tested for their antibacterial properties towards two distinct strains of bacteria. Antibacterial inspection demonstrated that ZnO nanoparticles were most effective against Staphylococcus aureus, followed by Escherichia coli. Furthermore, the anticancer potential treated with the ZnO nanoparticles was evaluated against the ovarian tumor cell line (SKOV-3), as well as the results suggest that the nanoparticles can function against an antiproliferative agent towards SKOV-3 cells. The present work illustrates the promise of biomedical applications of ZnO nanoparticles obtained by laser irradiation in water. [ABSTRACT FROM AUTHOR]

In this study, a novel, simple method has been used for fabricated of Au:TiO2 nanoparticles. The manufacture consisted of two steps: first, ablating a gold (Au) target immersed in CTAB solution to produce colloidal Au NPs and then inserting a titanium (Ti) target in the solution to prepare Au:TiO2 NPs via laser ablation in liquid (LAL) at various laser energies. Then, it was placed on porous-Si (PS). PS is made by etching n-type crystalline c-Si wafers by photo-electrochemical etching (PECE). The XRD, TEM, AFM, PL analyses were employed to characterize the samples. Lastly, the impact of varying operation temperature of hydrogen sulfide (H2S) and nitrogen dioxide (NO2) gas sensors fabricated from prepared specimens on the sensors sensitivity, response time, and time to recover was explored. We found the greatest sensitivity of Au:TiO2 NPs/PS when ablated at 1000 mJ. The synthesized Au/TiO2 NPs thin films show high sensitivity 94.12% and 42.69% with fast response and recovery of H2S and NO2 gas at for low concentration 12.6 and 64.5 ppm, respectively. [ABSTRACT FROM AUTHOR]

In this study, we synthesize Pd NPs by laser ablation in liquid with a wavelength of 532 nm and two energies of 360 and 800 mJ, and study the difference between them. In XRD diffraction, the crystal size increases by 21.7 and 24.21 nm, while the morphology of the Pd nanospherical in the TEM and SEM see average particles 19.4 and 27.5 nm, UV–vis spectroscopy showed the highest peak of absorbance 294 and 309 nm with energy band gap decreases 4.04 and 3.75 eV with increase laser energy. The examinations were suitable for photocatalytic. [ABSTRACT FROM AUTHOR]

In the current study, SnO2 nanoparticles were fabricated using laser ablation in water and characterized using ultraviolet-visible (UV-vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The XRD results showed that the fabricated nanoparticles had a tetragonal crystal structure. TEM micrographs revealed that the nanoparticles were spherical, with average sizes ranging from 10 to 50 nm, depending on the laser energy used. The band gap energy of the SnO2 nanoparticles was found to increase with decreasing particle size. The antibacterial activity of the SnO2 nanoparticles was tested against Staphylococcus aureus and Escherichia coli, and the results showed that the nanoparticles were more effective against S. aureus. In addition, the anticancer activity of the SnO2 nanoparticles was tested against the lung cancer cell line A549 cells, and the findings suggest that the nanoparticles can act as an anti-proliferative agent against A549 cells. This study reveals that SnO2 nanoparticles that are synthesized by laser ablation in water could be a future strategy for other biomedical applications such as antifungal, antiviral, and immune modulators. [ABSTRACT FROM AUTHOR]

The aim of this research study is the effect external magnetic field on the structural, morphological, electrical and optical properties of Au@TiO2 films grown under various laser pulse energy 500, 660, and 820 mJ/pulse, as well as its potential for photodetector application. This process was carried by second harmonic 532 nm a Q-switching Nd:YAG laser. X-ray diffraction indicates the formation of a creation crystalline Au@TiO2 core shell through the existence of XRD peaks associated with Au and TiO2 NPs, with no structural changes after applying a magnetic field. In the case of applying a magnetic field, TEM demonstrates the creation of spherical Au@TiO2NPs, with reduced agglomeration and particle size from 27 to 17 nm. The optical properties revealed that the optical energy gap of Au@TiO2NPs was 3.6 eV at the B = 0 T eV, while the energy gap increased under the influence of effect of magnetic field through the process of ablation. The current–voltage characteristics of Au@TiO2/PS photodetectors were measured in the dark conditions. The maximum responsivity of the Au@TiO2/PS photodetector was 0.16 A/W at 450 nm while this responsive decreasing to 0.04 A/W after applying the magnetic field through the ablation process. Au@TiO2NPs appear to be a potential candidate for high-performance photo-detector applications. [ABSTRACT FROM AUTHOR]

Gold-titanium dioxide nanoparticles (Au-TiO2 NPs) were synthesized via pulsed Nd:YAG laser ablation in the CTAB under the influence of an external magnetic field produced. Scanning electron microscopy (SEM), X-ray diffraction (XRD), UV–Vis spectroscopy, and transmission electron microscopy (TEM) have been utilized in order to analyze Au-TiO2 NPs. The XRD pattern related to Au-TiO2 NPs indicated that they have been polycrystalline and the specimens Au-TiO2 were nanocrystalline. In the case when applying a magnetic field, spherical NPs are generated, particle agglomeration is reduced, and particle size declines from 31 to 25 nm, according to SEM. Following ablation with a magnetic field, the optical energy gap of Au-TiO2 NPs increased from 3.5 to 3.7 eV. With current density–voltage (J-V) measurements, the electrical parameters of Al/Au-TiO2/PS/Si/Al heterojunction, including the barrier height (ΦB) and ideal factor (n), were indicated. The efficiency regarding Au-TiO2/PS photodetectors has been enhanced over various wavelengths, quantum efficiency (QE) of Au-TiO2/PS photodetectors has been reduced after adding a magnetic field during the process of ablation. [ABSTRACT FROM AUTHOR]

At room temperature (RT), Tin dioxide (SnO2) nanoparticles (NPs) have been created through pulsed laser ablation (PLA) of tin in various liquid mediums. FTIR, TEM, electrical characteristics and UV–Visible absorption spectrum were used for investigating the particle properties. The prepared material is spherical NP, with size and size dispersion are dependent upon liquid media, as seen by TEM micrographs. The shift of the Sn–O band from 681 cm−1, 663.4 cm−1 to 657 cm−1 in double deionize water, ethanol and methanol, respectively, could be related to the increase of the concentration of SnO2 NPS and change of particles size. Depending on the quantum confinement model, the band gap energy related to SnO2 NPs is larger in various liquid medium compared to that of bulk SnO2 because of a decrease in size of the particle. Poor rectification properties because of charge carriers' recombination of holes and electrons in depletion region, along with the tunneling effect based on the two sides of heterojunction and existence of defect states can be seen in the J–V characteristics of Al/SnO2 NPs/c-Si/Al heterojunction. [ABSTRACT FROM AUTHOR]

This work focuses on photodetector Au:MgO nano-particles (NPs) have been prepared by laser ablation at various laser energies then deposited on porous-Si (PS). PS are produced with the use of the photo-electrochemical etching approach for n-type crystalline Si wafers of (100) orientation. XRD, scanning electron microscope, UV–visible spector-photometer and electrical characteristics that have been utilized for characterizations of products. The photo-detector measurements, the spectral responsivity curves inclusive three regions; the first peak was due to absorption of the ultraviolet light by Au:MgO NPs. The second peak corresponding to the absorption of the visible light with porous silicon layer and the third peak to absorption edge of the Si substrate. The higher responsivity of Au:MgO NPs/PS photo-detector were found to be 3.29 A/W for specimen prepared at laser energy 800 mJ/pulse. [ABSTRACT FROM AUTHOR]

This study outlines the synthesis and analysis of nickel oxide nanoparticles (NiO) that are coated onto porous silicon (PS) to serve in photodetector applications. The synthesis of nickel oxide nanoparticles was achieved by employing pulsed laser ablation in water, while a PS layer was produced through light-assisted electrochemical etching. An investigation is conducted on the optical, structural, and optoelectronics characteristics of NiO-NPs/PS structures, focusing on their dependence on laser energy. The XRD analysis indicates the presence of distinct peaks corresponding to a cubic pattern, signifying the creation of nickel oxide nanoparticles on PS in the produced specimen. The field emission scanning electron microscope investigation verified that the suspension nanoparticles exhibited predominantly a sphere-like shape. The suspension of NiO nanoparticles appeared as an absorption edge at a wavelength of around 275 nm. Furthermore, it was observed that the absorption peaks became stronger with increased laser energy. The optical properties provide that the band gaps of the NiO NPs formed with laser energies between 400 and 800 mJ were identified, ranging from 4.98 to 4.85 eV, respectively. The photodetector measurements indicate that the NiO NPs/PS structures, formed at 700 mJ, exhibited maximum responsivity visible ranges of 0.065 A/W at 400 nm wavelength and 0.137 A/W at 600 nm wavelength. The results indicated that the spectral responsivity, detectivity, and quantum efficiency of the photodetectors comprised of p-NiO NPs/PS/n-Si were significantly associated with the laser energy employed to prepare the NiO NPs. The fabricated detector achieved its highest spectral response when the NiO NPs were prepared at an energy of 700 mJ. The NiO NPs/PS structures fabricated in this research, which integrate NiO NPs with Si nanostructure, suggest significant promise for deployment as highly effective photodetectors. [ABSTRACT FROM AUTHOR]

This research included the production of copper oxide nanoparticles (CuO NPs) using various pulsed laser ablation energy (PLAL) embedded in substrates made of porous silicon (PS). The PS substrates were created using the photoelectrochemical etching (PECE) technique of Si n-type (111). The research examined the impact of pulse laser ablation energy on many attributes of the created samples, involving their structural, electrical, optical, photodetector, and morphological properties. XRD analysis reveals a prominent and broad diffraction peak at an angle of 28.4ο for the porous silicon and other diffraction peaks at different angles, indicating the presence of the CuO NPs phase corresponding to the monoclinic crystal structure. The SEM image demonstrates that PS is sponge-like, while CuO NPs display randomly dispersed spherical grains, and appear to vary in the particle size due to the change in laser pulses energy. The optical properties of the fabricated specimens were analyzed utilizing photoluminescence and UV–vis absorption spectroscopy. The results suggested that a change in laser pulse energy caused a change in the energy gap that ranges from 2.7 to 3.5 eV. The created samples' current density-voltage (J-V) characteristics were analyzed under two conditions: in dark and light while varying the laser pulse energy. The J-V characteristics curves demonstrate that increasing the pulse energies of laser ablation resulted in higher current density flowing through the samples, particularly when the sample was created at 900 mJ. The photocurrent density exhibited a significant association with the increase in input light intensity, so enabling its utilization as a photodetector device. Nevertheless, altering the laser ablation pulse energy resulted in modifying the photocurrent for all CuO NPs/PS specimens. The inclusion of CuO nanoparticles in the PS samples led to a considerable enhancement in the responsivity (Rλ) when compared to the PS-only sample. The reason for this is that CuO nanoparticles have the ability to absorb light throughout a wide range of wavelengths, from ultraviolet-visible to near-infrared. The highest detectivity (D*) value was recorded when the laser energy was set at 700 mJ. The observed phenomena can be ascribed to fluctuations in the size or morphology of CuO NPs caused by variations in laser ablation pulse energy during its preparation. Furthermore, the constructed photodetector exhibited enhanced external quantum efficiency (Q.E), specifically in the ultraviolet (UV) range. The findings of this research are significant in the progress of optoelectronic and photodetector devices that rely on CuO NPs and PS. [ABSTRACT FROM AUTHOR]

A pulsed laser was used to make the Au@Ag@Au core-double shell nanoparticles in a DMF solution. The samples were characterized and inspected to confirm the structure investigated by XRD tests, and the average crystallite size was 51.988, 51.222, and 47.482 nm at laser energy 300, 500, and 700 mJ, respectively. Transmission electron microscopy (TEM) was employed to confirm the nanostructure of the particles. The particles were found to have a spherical form, with mean diameters of 15 nm, 9.5 nm, and 7.5 nm at laser energy of 300, 500, and 700 mJ, respectively. Showing the surface plasmon resonance peak for each gold and silver NPs, we observe a phenomenon a blue shift in absorption peak with increased laser energy, which signifies a reduction in the dimensions of the nanoparticles. The energy gap for samples was determined using Tauc’s relation, which were 1.52, 1.53, and 1.54 eV at laser energy 300, 500, and 700 mJ, respectively. The stability of the nanomaterials was assessed using zeta potential analysis, which measured the stability of every specimen in a DMF solution. The computed zeta potentials for the samples were − 19.6 mV, − 29.3 mV, and − 41.6 mV, at laser energy of 300, 500, and 700 mJ, respectively. After that, Au@Ag@Au core-double shells nanoparticles were tested as novel antimicrobial agents against Streptococcus mutans as well as Klebsiella pneumoniae. The results showed that the Au@Ag@Au core-double shells were great agents for killing both types of bacteria and inhibiting bacterial biofilm formation. The results collectively indicated that Au@Ag@Au NPs had the potential to serve as an alternate antibacterial agent. [ABSTRACT FROM AUTHOR]

This research study specifically examines the CuO@ZnO nanoparticle core–shell colloidal solution that is produced using Nd: YAG laser ablation. The laser used has pulse energies of 900, 700, and 500 mJ, a wavelength of 1064 nm, and repeated pulses of 200. This work demonstrated the characteristics of a colloidal solution containing CuO@ZnO NP core–shell deposited onto Si substrates using the drop-casting process. The TEM, SEM, XRD, and UV–vis spectroscopy techniques were used to investigate the morphological, shape, optical, and structural characteristics of the synthesized CuO@ZnO NP core–shell. The XRD analysis reveals that the CuO@ZnO NP core–shell has sizes ranging from 30 to 93 nm approximately. The nanoparticle core–shell exhibited a combination of spherical and irregular shapes with sizes ranging from 30 to 90 nm. The nanoparticle size appeared to be influenced by the variation in laser pulse energy, as evidenced in SEM pictures. The TEM pictures reveal that the core–shell nanoparticles exhibit a particle size distribution with average sizes of 19, 70, and 30 nm for the nanoparticles produced using laser pulses with energy levels of 900, 700, and 500 mJ, respectively. The TEM pictures also exhibit a dark central region of CuO NPs and a comparatively lighter outside region of the ZnO nanoshell, thereby verifying its core–shell structure. Alteration of the laser energy resulted in a noticeable change in the optical energy band gap in the generated samples. The results of the UV–vis test suggested that a change in the energy of the laser pulse caused a change in the energy gap that ranges from 2.6 to 3 eV. The dye degradation capability of CuO@ZnO NP core–shell has been evaluated using methylene blue (MB), an organic dye. The results indicate that all samples exhibited successful degradation using CuO@ZnO NP core–shell with differentiated activity levels. The blue color of the methylene blue solution vanished within 120 min of exposure to illumination when the CuO@ZnO nanoparticles, generated with a laser energy of 900 mJ, were present. The investigation of CuO@ZnO nanoparticles, synthesized through the use of laser pulse energy, demonstrates its potential as a highly effective substance for water purification. [ABSTRACT FROM AUTHOR]

This study investigated for the first time a simple bio-synthesis approach for the synthesis of copper oxide nanoparticles (CuO NPs) using Annona muricata L (A. muricata) plant extract to test their anti-cancer effects. The presence of CuONPs was confirmed by UV–visible spectroscopy, Scanning electron microscope (SEM), and Transmission electron microscope (TEM). The antiproliferative properties of the synthesized nanoparticles were evaluated against (AMJ-13), (MCF-7) breast cancer cell lines, and the human breast epithelial cell line (HBL-100) as healthy cells. This study indicates that CuONPs reduced cell proliferation for AMJ-13 and MCF-7. HBL-100 cells were not significantly inhibited for several concentration levels or test periods. The outcomes suggest that the prepared copper oxide nanoparticles acted against the growth of specific cell lines observed in breast cancer. It was observed that cancer cells had minor colony creation after 24 h sustained CuONPs exposure using (IC50) concentration for AMJ-13 was (17.04 µg mL−1). While for MCF-7 cells was (18.92 µg mL−1). It indicates the uptake of CuONPs by cancer cells, triggering apoptosis. Moreover, treatment with CuONPs enhanced Lactate dehydrogenase (LDH) production, probably caused by cell membrane damage, creating leaks comprising cellular substances like lactate dehydrogenase. Hence, research results suggested that the synthesized CuONPs precipitated anti-proliferative effects by triggering cell death through apoptosis. [ABSTRACT FROM AUTHOR]

Our research involved the synthesis of a double core-shell structure using gold and silver NPs. The core material used was gold. The initial shell had a silver coating, while the subsequent shell was encased in gold. The wavelength of the laser was 1046 nm and was employed, along with 250 pulses at a frequency of 1 Hz, delivering an energy of 500 mJ into 5 ml of deionized water; the focal length of the lens was 12 cm. A comparison was made between the double core-shell construction consisting of individual silver (Ag) and gold (Au) nanoparticles and the single core-shell structure. Various tests were conducted on the samples, including XRD, TEM, UV-visible, FTIR, and zeta potential, to analyze their characteristics. Additionally, the energy gap was determined for each sample. Next, the study examined the impact of particles with a double core-shell and single particles on S. aureus and E. coli bacteria. The findings revealed that a double coating exhibited exceptional effectiveness in eliminating bacterial cells when compared to single particles and a single core-shell. This was demonstrated through the implementation of a zone of inhibition and antibiofilm activity. They were able to verify the existence of the two metal substances (Au and Ag) in each and every sample by using X-ray diffraction (XRD). TEM images clearly depict the formation of the core-shell system. Also presented were TEM images of colloidal particles made of gold and silver, which were smaller than 10 nm in size. The formation of certain nanoparticles resulted in a shift in the peak wavelength, confirming the occurrence of a superficial overlap. The energy transition was calculated using the Tauc relation, with specific values for the different nanoparticles involved. Based on the zeta potential, it is observed that the stability of Ag NPs is greater than that of Au NPs. Additionally, the core double-shell structure formed is found to be less stable compared to the individual Au NPs and Ag NPs. During the ICP-MS analysis, it was observed that the amount of the double shells reduced in comparison to both the individual shell and the individual gold and silver particles. The particles were linked to each other to produce the shells. The current study suggested the potential role of Au@Ag@Au NPs for antibacterial applications in the future. [ABSTRACT FROM AUTHOR]

In this research, the production of zinc oxide nanoparticles (ZnO NPs) was made using various pulsed laser ablation energy (PLA) embedded in substrates made up of porous silicon (PS). The PS substrates were created using the photoelectrochemical etching (PECE) technique of Si n-type (111). The research examined the impact of pulse laser ablation energy for some features on the prepared samples that involved the structural, electrical, optical, and morphological properties in photodetector application. XRD analysis reveals a broad diffraction peak at an angle of 28.4° for the porous silicon with other diffraction peaks at different angles, indicating the presence of the ZnO NPs phase corresponding to the structure of hexagonal wurtzite. The SEM image demonstrates that PS is sponge-like, while ZnO NPs display randomly dispersed spherical grains. The optical characteristics of the fabricated specimens were analyzed using photoluminescence and UV-vis absorption spectroscopy. It was observed that an increase in laser pulse energy results in a shift of the absorption wavelengths and a change in the energy gap. The J-V characteristics of the created specimens were analyzed under two conditions: in dark and light while varying the laser pulse energy. The photodetectors consisting of ZnO NPs/PS/n-Si exhibited rectifying characteristics and remarkable responsivity to a wide range of wavelengths, from UV to near-infrared. Furthermore, the constructed photodetectors exhibited enhanced quantum efficiency (Q.E), specifically in the ultraviolet (UV) range. The results of this research are significant in the progress of optoelectronic and photodetector devices that rely on ZnO NPs and PS. [ABSTRACT FROM AUTHOR]

In this work, n-type porous silicon (n-PS) was fabricated via photoelectrochemical etching (PECE) method with different etching current densities, including 5, 10, 15, 20, and 25 mA/cm2 at constant concentration of HF about 20%. The suspension mixture of standard copper oxide nanoparticles (CuO-NPs) was prepared by dissolving 0.2 g of CuO powder in 100-ml ethanol. Then, CuO-NPs were deposited on n-PS surface employing the drop-casting method. X-ray diffraction and scanning electron microscope techniques proved the cubic crystal phase with porous morphology. The current–voltage (J-V) measurements were conducted in the dark and under illumination with different intensities for n-PS and CuO/PS samples. To evaluate the photodetector-sensing performance, the responsivity (Rλ), detectivity (D), and the quantum efficiency (Q.E) tests were performed for all samples at room temperature. All results showed that the CuO-NPs on the n-PS surface lead to increase Rλ, D, and Q.E compared with n-PS-only sample. [ABSTRACT FROM AUTHOR]

The synthesis of Au@NiO nanoparticles (NPs) core–shell involves a two-step method via laser ablation in aqueous solutions. Meanwhile, porous silicon is obtained using photoelectrochemically etching (PECE) of n-type silicon. The nanostructured Au@NiO deposited on a porous silicon layer is demonstrated using field-emission scanning electron microscopy images, X-ray diffraction, and UV–vis absorption measurements. The creation of core–shell structure in Au@NiO nanoparticles was confirmed using X-ray diffraction, EDS, and UV–visible spectroscopy techniques. X-ray diffraction investigation indicates that the structures of Au and NiO exhibit a cubic shape oriented in the (111) direction. The optical band gap of Au@NiO nanoparticles decreased as laser energy increased. The Al/Au@NiO NPs/PS/n-Si/Al photodetector prepared at a laser energy of 700 mJ showed a responsivity of 0.105A/W and low reflectivity. Furthermore, the designed photodetector displayed a broad response range covering many effective regions, ranging from ultraviolet to infrared. The findings of this work are highly significant for the progress of photoresponse and optoelectronic devices that depend on core–shell Au-NiO nanoparticles and porous silicon. [ABSTRACT FROM AUTHOR]

In the current study, polyethylene glycol (PEG) was employed to cap super magnetite nanoparticles (Fe3O4 NPs) through hydrothermal preparation. The main goal of this study is to investigate the influence of physical incorporation of polyethylene glycol (PEG) loaded Fe3O4. The anticancer potentials of these particles were studied against breast cancer cell line (AMJ13). Syntheses bare Fe3O4, and Fe3O4-PEG were confirmed by TEM, SEM, and FTIR. The size of Fe3O4 nanoparticles range of 9–20 and 5–12 nm for the Fe3O4–PEG nanoparticles which exerted superparamagnetic properties as well as elevated saturation level of magnetization at ambient conditions. The MTT test was employed to detect the ability of the bare Fe3O4 and Fe3O4-PEG on the proliferative of AMJ13 cells. IC50 values was 37.33 µg mL− 1 for bare Fe3O4 and 18.23 µg mL−1 for Fe3O4-PEG. AMJ13 Cells exposed to bare Fe3O4, and Fe3O4-PEG NPs demonstrated a significant cell death, which increased with PEG, loaded Fe3O4 NPs. The capability of Fe3O4-PEG to induce cellular apoptosis was tested using DAPI, Acridine orange/ Ethedium bromide stains, flow cytometry, with the assays of mitochondrial membrane potential (MMP), and the production of reactive oxygen species (ROS). RT-PCR, and immunofluorescence were performed to measure expression levels of Bax and Bcl-2 proteins. The toxicity of bare Fe3O4 and Fe3O4-PEG nanoparticles using animal model were investigated. Animal's body weight, liver and kidney function enzymes, and histological alterations for liver, kidney, and lungs were addressed. The findings demonstrated that nanoparticles were biocompatible with liver and kidney function enzymes and no significant alterations were recorded in the liver, kidney and the lungs. Both nanoparticles revealed a proliferation inhibitory effect on AMJ13 cells, resulting in apoptosis as a novel pathway that involve the mitochondrial damage and NF-kB. Taken together the present data suggest that bare Fe3O4 and Fe3O4-PEG could be promising therapy protocol for cancer cells. [ABSTRACT FROM AUTHOR]