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2018 Journal of Materials Science: Materials in Electronics
In this work, PAni nanofibers (NFs) are successfully synthesized via hydrothermal method. The structural, surface morphological, optical, electrical and H2S gas sensing properties have been investigated for PAni thin films deposited by spin coating technique. The XRD pattern reveals crystalline nature of PAni NFs with crystallite size of 9.2 nm. The SEM image of Polyaniline clearly indicates that the polymer possesses nanofiber like structure. The optical properties show that the optical energy gap follows allowed direct electronic transition calculated using Tauc’s equation. Intense photoluminescence (PL) peaks at 309, 340 and 605 nm are observed. The electrical properties such as D.C. conductivity and Hall effect have been studied where D.C. conductivity shows reversible insulator-to-metal electrical behavior. Hall measurements for PAni reveal p-type conductivity. The H2S toxic gas sensing properties of PAni NFs thin film are investigated as a function of time and operating temperature. High sensitivity (528%) was achieved at operating temperature of 200 °C with fast response and recovery times.
Effect of Aqueous Solution Molarity on Structural and Optical Properties of Ni0.92Co0.08O Thin Films Prepared by Chemical Spray Pyrolysis Method
2015 International Journal of Thin Films Science and Technology
Abstract: In this study, Ni0.92Co0.08O thin films with different molarities (0.05M, 0.1 M, 0.15M and 0.2 M) have been successfully deposited on glass substrates by chemical spray pyrolysis (CSP) technique at substrate temperature of (400 oC) and thickness of about 300 nm. The structural and optical properties of these films have been studied using XRD, AFM, and UV-Visible spectroscopy. The XRD results showed that all films are polycrystalline in nature with cubic structure and preferred orientation along (111) plane. The crystallite size was calculated using Scherrer formula and it is found that the 0.2M has maximum crystallite size (49.51nm). AFM results showed homogenous and smooth thin films. The absorbance and transmittance spectra have been recorded in the wavelength range of (300-900) nm in order to study the optical properties. The optical energy gap for allowed direct electronic transition was calculated using Tauc equation and First derivative of absorbance with respect to energy of photon. It is found that the band gap decreases when the molarity increases and the band gap values ranges between 3.60 eV and 3.54 eV for the prepared thin films. The Urbach energy increases as the molarity increases and the Urbach energy values range between 439 meV and 680 meV. The optical constants including (absorption coefficient, real and imaginary parts of dielectric constant) were also calculated as a function of photon energy. Refractive index and extinction coefficient for the prepared thin films were estimated as a function of wavelength.
2015 International Letters of Chemistry, Physics and Astronomy
In this work, nickel-cobalt oxide (Ni(1-x)CoxO) thin films, where x = 0, 4, 6 and 8 % have been successfully deposited on glass substrates by chemical spray pyrolysis (CSP) technique at substrate temperature of (400 °C) and thickness of about 300 nm. The structural and optical properties of these films have been studied using XRD, AFM, and UV-Visible spectroscopy. The XRD results showed that all films are polycrystalline in nature with cubic structure and preferred orientation along (111) plane. The crystallite size was calculated using Scherrer formula and it is found that the undoped NiO sample has maximum crystallite size (51.16 nm). AFM results showed homogenous and smooth thin films. The absorbance and transmittance spectra have been recorded in the wavelength range of (300-900) nm in order to study the optical properties. The optical energy gap for allowed direct electronic transition was calculated using Tauc equation. It is found that the band gap decreases as the Co-concentration increases and the band gap values were in the range of 3.58-3.66 eV and 3.58 eV for the prepared Nickel-Cobalt Oxide thin films. The Urbach energy increases as the Co-concentration increases and the Urbach. The optical constants including (absorption coefficient, real and imaginary parts of dielectric constant) were also calculated as a function of photon energy. Refractive index and extinction coefficient for Nickel- Cobalt Oxide thin films were estimated as a function of wavelength.
2014 International Journal of Current Research
In this work,NiO thin films at different molarities (0.05M, 0.1M, 0.15M and 0.2M)have been successfully deposited on glass substrates by chemical spray pyrolysis (CSP) technique at substrate temperature of (400 oC) and thickness of about 300 nm. The structural and optical properties of these films have been investigated using XRD, AFM, and UV-Visible spectroscopy. The XRD results showed that all films are polycrystalline in nature with cubic structure and preferred orientation along (111) plane. The crystallite size was calculated using Scherrer formula and it is found that the molarity 0.1M has maximum crystallite size (51.16nm). AFM images showed homogenous and smooth NiO thin films and the average grain size estimated from the AFM granularity report confirms the XRD results. The absorbance and transmittance spectra have been recorded in the wavelength range of (300-900) nm in order to study the optical properties.The optical energy gap for allowed direct electronic transition was calculated using Tauc equation. It is found that the band gap decreases when the molarity increases and the band gap values range between 3.71 eV and 3.59 eV for the preparedNiO thin films at different molarities. The Urbach energy increases as the molarity increases and the Urbach energy values range between 299 meV and 343 meV.The optical constants including (absorption coefficient, real and imaginary parts of dielectric constant) were also calculated as a function of photon energy. Refractive index and extinction coefficient for NiO thin films were estimated as a function of wavelength.
2019 JOURNAL OF NANO- AND ELECTRONIC PHYSICS
In this work, pure and copper mixed oxide PAni nanofiber thin films are successfully synthesized on silicon substrates by hydrothermal method and spin coating technique at room temperature with thickness of about 325 nm. The structural, surface morphological, optical and photoconductivity properties have been investigated. The XRD results showed that PAni films have crystalline nature, CuO and PAni/CuO nanostructure composites are monoclinic polycrystalline structure. The FESEM images of PAni clearly indicate that it has nanofiber-like structure, whereas the CuO film has sponge- like shape. The surface morphology analysis of PAni/CuO composite shows that nanofiber caped with inorganic material which is CuO is a core-shell structure. Optical characterization shows that the direct electronic transition is allowed in the energy gap. The values of energy gap for PAni nanofibers and CuO are 3.98 eV and 5.29 eV respectively. The spectral response of PAni nanofibers, CuO and PAni/CuO composite was studied. The values of responsivity and quantum efficiency of PAni/CuO composite are larger than those for pure PAni nanofibers. One can conclude that with mixing, the sensitivity is higher than that without mixing and is found to be 220 %. PAni/CuO composite exhibits fast rise time of 0.32 s with full time of 0.41 s, while slow rise time of 0.67 s and 0.38 s was respectively observed for PAni nanofibers and CuO with full time of 3.32 s and 1.19 s.
2020 Journal of Electronic Materials
Polyaniline nanofibers (PAni NFs) were successfully prepared using a hydrothermal technique. The spin-coating method was employed for depositing polyaniline nanofibers in different solvents such as water, 2-methoxyethanol and ethanol. During this process, surface morphological, optical, structural, and hydrogen sulfide (H2S) gas-sensing properties have been investigated for the polyaniline nanofibers. The results of the x-ray diffraction pattern showed a peak around 2θ ∼25°, which is referred to the (200) desirable direction for all samples. A field-emission scanning electron microscopy analysis of PAni showed NFs as a structure for all the films. Fourier-transform Infrared patterns confirmed the creation of the PAni. The preparation process of PAni NFs using water showed that a smaller energy gap value was realized during the optical properties examination. What is more, the solvent absorption studies indicated that the highest energy gap value was realized for 2-methoxyethanol. The H2S gas-sensing properties of PAni NFs films showed high sensitivity (23.67%) being achieved at the operating temperature of 150°C with a very fast recovery time and response time for PAni NFs that were prepared using water.
2020 Chemical Data Collections
In this study, mixed Nickel- Copper oxide (NiO)1-x(CuO)x thin films were deposited on glass substrates using chemical spray pyrolysis technique at substrate temperature of 400 °C and thickness of 200 nm. UV-Visible spectroscopy and X- ray diffraction (XRD) were used to study the optical and structural properties of films. The optical energy gap for the thin films was estimated using Tauc's function. It is observed that the band gap decreases with the increase of the mixing ratio of copper oxide. The constants of optical properties contain absorption coefficient as a function of photon energy. Extinction coefficient for all samples was estimated as a wavelength function and the refractive index increased as (CuO) contents increased. The results of XRD showed that these films were polycrystalline in nature with orientation along (111) plane. The average values of crystallite size was estimated by using Scherrer's method and W-H questions are found to increase as the (CuO) contents increased.
2020 Int. J. Nanoelectron. Mater
In this study, the sol-gel process has been adopted for the synthesis of Cu1-xAlxO nanostructures (0≤ x ≤ 0.90, in steps of 0.10). The system revealed pure CuO phase with monoclinic structure. Al2O3 phase and copper oxide (Cu2O) were developed at higher substituent concentrations till x=0.40. Structural properties were studied by X-ray diffraction (XRD) and morphological properties by Scanning Electron Microscope (SEM). Average crystallite size from the range of 12.65 nm to 22.9 nm was calculated by Scherer formula. The SEM images indicated that the Cu1-xAlxO possessed nanoparticles like structure, i.e. it contained some pores or voids and vacancies caused by a difference in experimental conditions. Results of EDX revealed the presence of Aluminum (Al), oxygen (O) and copper (Cu) elements in Cu1-xAlxO and the data showed that the nanoparticles were nearly stoichiometric.
2024 JOURNAL OF NANO- AND ELECTRONIC PHYSICS
"In this work, we used electrochemical etching of p-type silicon wafers for 10 min at a current density of 10 mA cm – 2 to obtain p-type porous silicon. Zinc oxide nanoparticles were produced using a chemical pre- cipitation method (CPM) and applied to (glass, PSi) substrates using (DCM). XRD and UV-Vis have also been used to study the properties of films (structural and optical). According to the XRD data, the ZnO NPs are wurtzite-structured polycrystalline, with a favored orientation along the (101) plane. The size of the ZnO NP crystals was measured by the Scherrer formula and the crystal size was found to be 22.04 nm. Images and distribution plots obtained using atomic force microscopy (AFM) indicated that the p-PSi had a particle size of approximately 47.22 nm and a porosity of (48 %). An ultraviolet (MS) detector based on porous (Si)/ZnO NPs (metal semiconductor) was fabricated at a temperature of (85 °C). The fabricated device showed a maximum detector photoresponse of 2.08 A/W at a wavelength of 450 nm at a bias voltage (+ 3.35 V). The factory-made UV ZnO detector has a normalized detection (D*) of approximately (2.9  1013) cm. 1/2 Hz/W at ( = 450 nm). This approach provides an economical substrate and a facile synthetic method for optimizing the growth of pPSi/ZnO NPs, This has led to the successful fabrication of nanoscale photodetectors with potential applications for nanoscale photodetectors is displayed. "
2023 AIP Conference Proceeding
In direction to decrease the eyelashes and eyelids effecting on the iris acknowledgment rate, an eyelashes finding algorithm are projected based on the overlapped eyelashes points appear dark pixels(black), and they may locate at the upper and lower side of the image; while the overlapped eyelid points appear bright (white) pixels. Also, it may appear at the upper, and lower, sides of the iris image. Based on the iris normalization, image enhancement with histogram equalization is used to accurately localize eyelashes and eyelids. The investigational effects show that compared with traditional eyelashes and the eyelids finding algorithm, it isn’t essential of algorithm to set up additional parameter, which expresses the simplicity to maximizing the result of the eyelashes and the eyelids segmentation.
2023 AIP Conference Proceedings
In this study, prepared the zirconia-alumina composites powders with weight ratios using aqueous aluminum nitrate and aqueous zirconia nitrate according to the molar fraction method of (A1) sample and using the molar fraction method in finding the weight ratios for each of the raw materials used in the preparation of the composites according to the following formula (ZrO2 (0.3-AI2O3(0.7)) and the ratio (2 from aluminum and 1 from zirconium) is from the raw materials, and the second sample (A2) according to the traditional ceramic method of direct quantities and is in a ratio (1 to 1) from the raw materials and by the method of common chemical precipitation and using dilute ammonia with a concentration of 30-33 The acidic function=10 as a strong base for precipitation to obtain the hydroxides of the materials and the sintered primary sintering at Heat of 600 oC for 4 hours and then a final sintering at 1300 oC for four hours. X-ray diffraction pattern spectroscopy (XRD-patterns) of the compound powders prepared at a temperature of (1300 oC) showed that the first sample was at the weight ratio A1 of the primary alumina-button superimposed and formed with two different phases, phase α-AI2O3 and orthogonal phase of zirconia t-zro2. As for the second sample the predominant phase is the orthogonal phase of zirconia t-zro2 with some phases of alumina. Fourier transformations of the infrared spectrum (FTIR) of the powders prepared at a temperature of (1300 oC) showed that they formed the required phases and were pure due to the high sintering temperature and were within the numbers less than (1000cm−1).
2021 Journal of Physics: Conference Series

In this work, nanostructured Mn3O4 thin films at different of thickness (200, 250, 300, 350) nm were deposited on substrate made from glass by chemical spray pyrolysis technique with substrate temperature at 400 °C. However, during this process, The structural and optical properties of these films have been investigated using XRD, and UV-Visible spectroscopy. The X-ray Diffraction (XRD) results showed that all films are polycrystalline in nature with tetragonal structure and preferred orientation along (211) plane. The crystallite size is determined by Scherer's formula and W-H analyses and it is found that it decreases as the thickness increasing. The optical energy gap for allowed direct electronic transition was calculated using Tauc equation. It was found that the band gap decreases when the thickness increasing. The variables of the optical properties containing (coefficient of absorption, parts of real and imaginary for dielectric constant) and estimated as a function of the photon energy. Coefficient extinction of thin film was valued as a wavelength function.

2021 IOP Conference Series: Earth and Environmental Science

In this work, tin oxide thin films were successfully synthesized by hydrothermal method and depositing on silicon substrates by spin coating technique at room temperature with thickness of about 325±5 nm. The structural, surface morphological, optical and gas sensor properties have been investigated. The XRD results showed that SnO2 films are polycrystalline in nature with tetragonal. The FESEM images of SnO2 clearly indicate that the oxide possesses has like cauliflower like shapes. The optical properties show that the optical energy gap follows allowed direct electronic transition calculated using Tauc's equation. The H2S toxic gas sensing properties of SnO2 thin film are examined as a function of time and operating temperature. High sensitivity (197%) was attained at operating temperature of 200 °C with fast response and recovery times.

A New Neuron Ion Channel Model Under Time Varying Input Currents
2021 Journal of Physics: Conference Series

In recent years, it has been argued and shown experimentally that ion channel noise in neurons can cause fundamental effects on the neuron's dynamical behavior. Most profoundly, ion channel noise was seen to be able to cause spontaneous firing and stochastic resonance. However, Hodgkin-Huxley model affected when inserting some colored noise terms inside the conductance's, where those effects captured by colored noise due to the gate multiplicity. This paper presents a new ion channel model under time varying periodic input currents. It firstly introduced the effect of without, with (colored noise), on the proposed model and the comparison of ion channel based on HH, Fox-Lu, and Linaro models. Additionally, in order to overcome the limitations of other parameter estimation methods, the proposed method fully constraints their models and obtains all models capabilities of reproducing the data. Finally, the …





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