High purity, micro, and nano size Ag2O nanostructure films were deposited by pulsed laser deposition on the quartz substrates at different pulsed laser Energies. The Ag2O cubic structure is supported by structural and optical features, with the primary diffraction occurring from the (002) plane. The obtained band gap energy was around 2.25eV, and optical features indicate the temporal dependency of the energy gab.

Zinc oxide nanorods zinc oxide nanowire has been deposited on quartz employing a hydrothermal method. The ZnO nanoroad as a seed layer were prepared for the growth process using the drop-casting method. The zincoxide nanomaterials produced were characterized by UV–Visible spectrophotometers, x-ray diffraction, Scanning electron microscopy ,. The crystal structure was calculated from the XRD data and it was confirmed the growth of wurtzite crystalline crystal structures of ZnO NRs. The SEM images revealed high-density nanowires were grown via drop cast coated seed layer. The bandgap in the ZnO NRs film was found to be 3.28 eV. This result was confirmed the formation of ZnO nanostructure. The thermal and electrical properties of ZnO NRs were measured also and analyzed. The conductivity of the ZnO NRs film was modified with the addition of gold nanoparticles using the sputtering technique. These modified films were promising and give an optimized temperature sensor performance.

In the present work, a zinc sulfide (ZnS) nanostructure film is deposited on multi-walled carbon nanotubes (MWCNTs) by means of pulsed laser deposition technique. The structural, morphological, and optical properties of ZnS-decorated MWCNTs are investigated. X-ray diffraction (XRD) studies showed the presence of peaks related to polycrystalline faced-center cubic ZnS and MWCNTs. The best crystallinity is found for ZnS/MWCNTs nanocomposite prepared at 5.3 J/cm2. Scanning electron microscope (SEM) investigation shows that the deposited ZnS films have a smooth structure with some spherical particles attached to the film surface. The SEM image of the ZnS-decorated MWCNTs confirms the formation of a nanocomposite morphology structure. The optical energy gap of ZnS film decreases from 4 to 3.85 eV as laser fluence increases from 5.3 to 6.5 J/cm2, and in addition, the energy gap of ZnS-decorated MWCNTs nanocomposite film is smaller than that of ZnS film. The current-voltage characteristics of ZnS/Si and ZnS-decorated MWCNTs/Si heterojunction photodetectors are measured in dark and illumination conditions. The responsivity of n-ZnS/p-Si and n-ZnS/MWCNTs/p-Si prepared at 6.5 J/cm2 was found to be as high as 0.35 at 710 nm and 0.674 A/W at 610 nm, respectively. The figures of merit of the ZnS/Si photodetectors, including external quantum efficiency and specific detectivity, were improved after being embedded with MWCNTs. The band lineup of n-ZnS-decorated MWCNTs/p-Si under illumination was constructed.

In this study, tellurium oxide (TeO2) nanoparticles were synthesized via PLA of tellurium targets with a 1064 nm laser in distilled water. The morphology and the particle size of the nanoparticles were characterized by scanning electron microscope (SEM) and atomic force microscope (AFM) respectively. The optical properties were studied by UV-Visible Spectrophotometer. Tellurium oxide nanoparticles with diameters of 55 nm were formed in a colloid solution. The UV–vis spectrum of the material shows a strong peak of around 200 nm. In addition, the morphology of gram-negative bacteria and gram-positive attachment of TeO2 nanoparticles was studied by using SEM measurement. The activity of TiO2 nanoparticles toward the inhibition and removal of Escherichia coli, Proteus, Pseudomonas bacteria and Staphylococcus aureus was investigated and discussed.

Zinc oxide nanowires (ZnO NWs) were successfully synthesized by Zn-metal evaporation and deposition of a thin metal film about 20 µm on quartz substrates. Followed by the subsequent oxidation process in the air at 550 oC for 4h. Copper oxide nanoparticles (CuO NPs) were then deposited on ZnO NWs, using the drop-casting technique. The crystal structure and morphology of ZnO nanowires were investigated by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results of XRD confirmed that the ZnO has the Wurtizite polycrystalline structure along [101] direction. The SEM images revealed that the highest density of ZnO nanowires was distributed over a large area of the substrate with many wrinkles. The current response to glucose of the CuO/ZnO/Qz electrode gives a linear dependence range from 50 µM to 500 µM of glucose. The typical sample of CuO/ZnO NWs was used for a glucose biosensor electrode. It was found that CuO NPs layer on ZnO NWs has well improved the performance of the electrode and increased the electrocatalytic ability towards glucose oxidation.

Zinc oxide flower-like nanorods (ZnO NRs) was successfully synthesized via the hydrothermal method. The growth process was conducted with seed layer concentrations of 20mM. The as-synthesized nanostructures were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM), and ultraviolet-visible (UV-VIS) spectrophotometer. The analysis results revealed a pure Wurtzite ZnO hexagonal nanostructures with preferred orientation (002) along the c-direction. The calculated band gap of average crystallite size is 3.2eV and 25 nm respectively. New designed, constructed and successfully calibrated for ethanol gas sensing was found. The ethanol gas sensor was fabricated at room temperature based on the ZnO NRs film. The synthesized materials proved to be a good candidate for the ethanol gas sensor. The optimum results of the gas sensor measurements of the synthesized gas sensor are as follows, the sensitivity, response time, and recovery time at 25 °C are 60%, 80 Seconds and 80 seconds respectively, and at 200 °C are 70%, 60 seconds and 50 seconds respectively.

In this work, atypical zinc oxide nanorods (ZnO NRs) on quartz substrates were successfully synthesized using simple, low-cost, and environmentally friendly hydrothermal method. The ZnO NRs were grown on a pre-seeded seed layer of ZnO nanocrystals using the spin coating process. Gold nanoparticles (Au NPs) were sputtered on the ZnO NRs film. The structure and morphology of the produced nanostructures were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The XRD analysis revealed that the ZnO NRs were single crystalline with hexagonal wurtzite structure grown with preferred orientation of (002). The SEM morphology shows a semi-hierarchical ZnO NRs with an estimated diameter of 200–400 nm and length of 4–5 μm. The optical properties of the ZnO NRs film were investigated using UV-visible spectrophotometers. The obtained bandgap of ZnO film was 3.0 eV. Electrical and thermal properties were also measured. The resistance changes versus temperature variation of ZnO NRs were given a semiconductor behavior. The gas sensor was fabricated based on bare ZnO NRs and Au NPs/ZnO NRs hybrid. The second nanostructure exhibited an enhanced sensor sensitivity toward ethanol gas at an optimized working temperature of 325 °C.

A photo detector was fabricated based on ZnO nanorods (NRs) on silicon substrate. The ZnO nanostructures were synthesized via hydrothermal method. The structure, morphology, and optical properties were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and UV–Visible spectrophotometer. XRD result, shows that the ZnO NRs is a hexagonal Wurtzite structure with preferred orientation (002) along the c-axis and the SEM photographs illustrate the average diameter and length of the ZnO nanorods were around 400 nm and 4 μm, respectively. The detector measurements revealed that the current–voltage characteristics of the ZnO NRs are asymmetrical, showing rectifying, diode-like behavior and the asymmetry factors (Id/Iph) about 13 at 5 V bias voltage was obtained. It was found that the, current under illumination was almost much higher compared with the dark current at − 5 V. The ZnO nanorods seem to be promising materials for high responsivity photo detector about 0.25 A/W and 0.29 A/W at 390 nm by applying a bias voltage of 0.5 V and 1 V respectively, with maximum quantum efficiencies of ZnO NRs 79% and 92% at the same bias voltage, which provides a route to fabricate a good UV photo detector.

In this work Cu7S4 thin films were synthesized successfully on glass substrates by a simple and cost-effective chemical bath deposition method. These films were annealed at various temperatures of 150 °C, 250 °C, and 350 °C. The influence of the annealing temperature on the structural, morphological, optical, and electrical properties was investigated. XRD analysis revealed that the as-prepared and post-annealed films are anilite Cu7S4, AFM measurements proved the films were free of voids and cracks with homogeneous surfaces, optical measurements revealed a blue shift in the band gap of about 0.54 eV as compared to that of bulk Cu7S4, while electrical measurements indicated the films have high conductivity. The optimum result is achieved in the films annealed at 150 °C where highest crystallinity, low crystallite size, and highest conductivity are recorded. This could be used for many applications such as optoelectronics, solar cell, and gas sensors.

In this work, ZnO nanorods (ZnO NRs) were successfully synthesized on FTO-glass via hydrothermal technique. Two steps were followed to grow ZnO NRs. In the first step, the seed layer of ZnO nanocrystals was deposited by using a drop cast method. The second step was represented by the hydrothermal growth of ZnO NRs on a pre-coated FTO- glass with the seed layer. The hydrothermal growth was conducted at 90∘C for 2[Formula: see text]h. The resulted structure, morphology and optical properties of the produced layers were analyzed by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) equipped with energy dispersive X-ray (EDX) and UV-visible spectrophotometer, respectively. The analysis confirmed that the ZnO NRs grown by the hydrothermal method have a hexagonal crystal structure which was grown randomly on the FTO surface. The crystallite size was recorded 50[Formula: see text]nm and a slight microstrain (0.142%) was calculated. The bandgap was found to be in the range of 3.14–3.17[Formula: see text]eV. The ZnO NRs have a high density and large aspect ratio. A pH sensor with high sensitivity was fabricated using a two-electrode cell configuration. The ZnO NRs sensor showed the sensitivity of [Formula: see text]59.03[Formula: see text]mV/pH, which is quite promising and close to the theoretical value ([Formula: see text]59.12[Formula: see text]mV/pH).

Antibacterial activity of CNSs against Staphylococcus aureus and Escherichia coli was estimated. Higher inhibition zone of 18 mm and 20 mm were observed against S. aureus and E.coli, respectively, at a concentration of 2 mg/ml of carbon nanosphere after 24 hrs of incubation at 37 ºC. In vitro cytotoxicity experiment was performed on two parasite strains of Leishmania donovani and Leishmania tropica by using MTT assay. L. donovani revealed more sensitiv to the CNSs than L. tropica. An intermediate level of cytotoxicity of 51.31 % was observed when 2.4 mg/ml of CNSs was incubated with L. donovani, while weak cytotoxicity of 37.20 % was shown when the same concentration of CNSs was used against L. tropica within 24 hr at 37 ºC.

Tin oxide nanowires (SnO2 NWs) were grown on quartz and silicon substrates via a modified chemical vapor deposition (CVD). Film of gold nanoparticle deposited on both types of substrates using the direct current DC-sputtering technique. The structure and morphology of the produced material were characterized by using atomic force microscopy, X-ray diffraction (XRD), scanning electron microscope (SEM) and ultraviolet–visible (UV–Vis) techniques. The XRD and SEM analysis confirmed the formation of tetragonal SnO2 NWs with a wire length of 10–20 μm and a diameter of 40–100 nm. The UV–Vis spectrum shows a strong absorption peak in the UV and others in the visible regions. The bandgap was calculated for SnO2 NWs grown on a quartz substrate within the value of 3.2 eV. It is slightly lower than the bandgap value of bulk. The successfully synthesized SnO2 NWs via CVD with a large aspect ratio in the range of 250–200 was proved to be quite promising nanomaterials to use for sensor fabrication towards ethanol gas at room temperature. The high sensitivity of 2.7 at an ethanol gas concentration of 500 parts per million (ppm) was achieved. The proposed sensing mechanism of SnO2 NWs towards ethanol gas was also discussed.

ABSTRACT In this paper, Indium oxide nanowires (In2O3 NWs) were successfully synthesized on quartz substrate pre-coated with gold nanoparticles (Au NPs) using chemical vapor deposition (CVD). The nanowires were characterized via x-ray diffraction (XRD), scanning electron microscope (SEM), Ultraviolet-Visible (UV-VIS) spectrophotometer. The sputtered of Au NPs on quartz were analyzed by atomic force microscopy (AFM). The structural, morphological, and optical properties were investigated. The XRD structure reviled a single crystal, with cubic crystal, with preferred orientation along (222). The SEM revealed nanowires growth. The obtained band gap value of 3.6 eV confirmed the formation of In2O3 nanostructures. Regarding to the characteristics of In2O3 NWs, it was fabricated as an ethanol gas sensor at 10-1500 ppm and an optimized temperature of 210 oC. The minimum ethanol gas response of Ra/Rg = 1.6 was obtained at a concentration of 10 ppm. The corresponding response and recovery time were achieved at the lowest concentration of 10 ppm is 10 s and 10 s respectively. So, the In2O3 NWs film synthesized via CVD can be considered as a good ethanol gas sensor device at low concentration. In2O3 NWs growth and gas sensing mechanism were also explained.

In the present work, we have synthesized ZnO nanorods (ZnO NRs) by using hydrothermal technique. The morphological, structural and optical properties of ZnO NRs were investigated using x-ray diffraction (XRD), scanning electron microscope (SEM) and UV–Vis absorption. XRD pattern confirms the deposited film was highly oriented crystalline ZnO NRs along [002] direction. SEM shows the formation of submicron and NRs morphology. The optical absorption studies depict that the optical energy gap of the film was 3.5 eV. The fabricated n-ZnO NRs/p-Si heterojunction photodetector exhibits rectification properties with an ideality factor of 2.2. The highest responsivity and quantum efficiency of the photodetector were nearly 0.27 A/W and 89% at 350 nm, respectively, without using buffer layer.

This works successfully synthesized vertically aligned, high density, long, large aspect ratio of CuO nanowires (CuO NWs) via thermal oxidation of copper (Cu) foil with atmospheric air. The oxidation process was conducted under temperature and time variation. The morphology and structure properties of CuO NWs were investigated by scanning electron microscope (SEM) and X-ray diffraction (XRD) respectively. UV-Visible spectrophotometer was also used to estimate the direct band gap (1.75eV) from the transmission spectrum. Furthermore, the film exhibit high absorption in the visible range and near infrared wavelength. The optimized parameters for long, small diameter, high density of CuO NWs at oxidation temperature of 500 degrees C for 6-8h in the atmospheric air were found. The diameter and length of CuO NWs was determined within the range of 50-100 nm and 20-30 mu m respectively. These optimized properties of CuO NWs make it a dependable candidate for visible light/near-infrared (NIR) photodetector fabrication. Therefore, the photodetector measurements were proved to render an acceptable performance.

Zinc Oxide nanorods (ZnO NRs) were successfully synthesized via hydrothermal method. The growth process was conducted with seed layer concentration of 30 mM. The as-synthesized nanostructures were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM), and ultraviolet-visible (UV-VIS) spectrophotometer. The analysis results revealed a pure Wurtzite ZnO hexagonal nanostructures with preferred orientation (002) along c-direction. The calculated band gap and crystallite size are 3.2 eV and 53.18 nm respectively. A methanol gas sensor was fabricated based on the annealed ZnO NRs on the silicon substrate. Optimized sensitivity at 250 ppm methanol vapor with fast response and recovery time was achieved. So, ZnO NRs film can serve as a good candidate for a methanol gas sensing device.

Controllable and predefined absorption are essential in the synthesis of new optoelectronic devices. In this work, an ion coater unit with a modified chamber is used to sputter the gold nano-islands onto glass substrates. Empirical formula and field emission scanning electron microscope (FESEM) is utilized to estimate the nominal thicknesses of the nano-island. Atomic force microscopy (AFM) images showed low values of roughness for the ultrathin films. The FESEM reveals that most of the nano-islands have round shapes. The UV-VIS measurements demonstrated that gold nano-islands revealed two regimes of absorption. Moreover, the peaks of surface plasmon resonance, in particular, are shifted to longer wavelengths and broadened in width with an increased thickness from 12-120 nm. In reverse to this behavior, the peaks are blue shifted for nominal thicknesses lower than 12 nm. The enhanced absorption in the blue spectral region can be utilized to increase absorption in solid-state solar cells and enhanced the stimulated Raman scattering devices using predefined thickness and deposition parameters.

The oblique angle configuration has emerged as an invaluable tool for the deposition of nanostructured thin films. In this article, we use this technique to investigate the optical properties of cadmium oxide nanostructure. Cadmium metal was deposited normally (θ= ̊0) and obliquely at different angles (50o and 70o) by using vacuum evaporation technique on a quartz substrate, then oxidized in air at 773K for the 1:30 hour.The absorbance and transmittance spectrum have been investigated by using UV-Visible spectrophotometer in the range300-1100nm. The optical energy gap (Eg), refractive index (n), extinction coefficient (k), real dielectric constant (εr) and imaginary dielectric constant (εi) have been determined.

Abstract Single phase, adherent films of copper oxide nanowires (CuO NWs) were successfully grown on a glass substrate. Titanium nanofilm was pre-coated on the glass substrate to assist the growth of a layer adherent to the substrate. The copper film of 1.5 μm thickness was deposited via physical vapor deposition technique followed by thermal oxidation in air at various temperatures for 4 h. The product was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet-visible (UV-Vis) and Fourier transformation infrared (FT-IR) spectroscopy to find the crystal structure, morphology, phases, and optical properties of the deposited films. The CuO NWs film with 60% transmittance at wavelengths greater than 800 nm was obtained. It can be used as an infrared thermal imaging filter and in optoelectronic devices. The fabricated temperature sensor exhibited high sensitivity in the temperature range of 20 °C to 180 °C.

Simple, low cost and environmental friendly oxidation methods were used to prepare cupric oxide (CuO) nanostructure films. Thin films of copper metal were deposited on various substrates (glass, silicon, and quartz) using a physical vapor deposition technique. The deposited copper films were thermally oxidized for 1 h at different temperatures (400, 500, and 800 °C) under air in a horizontal quartz tube furnace. The morphology and structure of the materials were characterized by scanning electron microscope and X-ray diffraction spectroscopy respectively. The lattice constant and crystallite size revealed a dependence on oxidation temperatures. CuO nanostructures were found as a promising material for fabrication of visible photodetector and temperature sensors based on different types of nanostructures and substrates.