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Published Journal Articles

2021

Synthesis and characterization of lead oxide nanostructures for radiation attenuation application

2021-04
Materials Science in Semiconductor Processing (Issue : 1) (Volume : 130)
In this study, lead oxide nanostructures (PbO NSs) were synthesized using chemical bath deposition method (CBD). The physical vapor deposition (PVD) technique used to deposit lead oxide seed-layer on the glass substrates. The effects of different deposition time on the morphology, structural and optical properties of lead oxide NSs were studied. Also, the radiation attention coefficient was measured based on synthesized lead oxide NSs with different deposition times. It was observed the alteration of growth time from 5 min to 20 min leads to significant change in morphology from nanofiber like lead oxide structure to the nanoflower like PbO structure. The XRD results, displayed the lead oxide NSs were indexed as Pb3O4 polycrystalline tetragonal phase. Also, the crystal size was in the range of (15.37–85.68) nm, and the growth rate was gradually decreased from 1.9 nm/min to 0.4 nm/min with deposition time from 5 min to 20 min. The synthesized PbO NSs have high transmittance (~80%) in the visible spectrum and low transmittance in the UV region. The energy band gap (Eg) values of the PbO NSs were changed from (2.20–2.36) eV with increasing growth time up to 20 min. The fabricated PbO NSs exhibited a significant performance in radiation shielding. The average radiation attenuation was changed from (14.592–48.642) count/sec as the deposition time increased from 5 min to 20 min. The higher rate of radiation attenuation for PbO NSs was observed at 10 min of deposition time and it was about 14.592 count/sec. The linear attenuation coefficient and half value layer were altered in the range of (226.132 m-1 -1142 m-1) × 104 and (6.0671–30.646) × 10−8, respectively. Also, the minimum and maximum transmission factor was observed for lead oxide NSs fabricated with 10 min and 20 min respectively. In addition, the maximum radiation protection efficiency was estimated for lead oxide NSs at 10 min and it was about 70%.

Effect of different pH values on growth solutions for the ZnO nanostructures

2021-03
Chinese Journal of Physics (Volume : 71)
In this study, high quality zinc oxide (ZnO) nanostructures were synthesized on glass slide substrates using modified chemical bath deposition (M-CBD) method at low temperature. Through the M-CBD technique the air bubbles will be injected into aqueous growth solution. The RF magnetron sputtering method was utlized to grow ZnO seed layer on the glass substrates. The effect of different pH values of aqueous growth solution on the morphology, elemental chemical composition, crystal structural and the optical properties of ZnO nanostructures have been investigated using field emission-scanning electron microscopy (FE-SEM), Energy dispersive analysis (EDX), X-ray diffraction (XRD), and UV-Visible Spectrometer, respectively. It was observed that altering pH values from acidic to alkaline (basic) by using ammonia solution (NH3) induced the significant change in morphology from nanorods like ZnO to nano-amber flush rose like ZnO structures. Furthermore, increased pH values had an effect on the influence intensity of the preferred orientation plane (002) and average transmittance spectrum. Whilst the absorption band edge has been shifted to a lower energy region due to the quantum size effect. It was also found that the crystal size fluctuated between 36.30 nm and 84.33 nm with a different values of pH from 6.7 to 12. The ZnO synthesized at 6.7 of pH provided the best results regarding the high aspect ratio,structural and optical properties. At this pH value, ZnO growth revealed the nanorod structure with small diameters, size and a higher energy band gap value.

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

2021-03
Nanomaterials (Issue : 3) (Volume : 11)
Ultraviolet (UV) photodetectors (PDs) based on high-quality well-aligned ZnO nanorods (NRs) were fabricated using both modified and conventional chemical bath deposition (CBD) methods. The modified chemical bath deposition (M-CBD) method was made by adding air bubbles to the growth solution during the CBD process. The viability and effectiveness of M-CBD were examined by developing UV PDs based on ZnO NRs. The ZnO nano-seed layer was coated on a glass substrate utilizing radiofrequency (RF) sputtering. The impact of the different growth-times on morphology, growth rate, crystal structure, and optical and chemical properties were investigated systematically using different characterization techniques, such as field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) analysis, UV–VIS double beam spectrometer, and energy dispersive X-ray analysis (EDX), respectively. The Al/ZnO UV PDs based on ZnO nanorods were fabricated with optimum growth conditions through the two methods of preparation. This study showed that the synthesized ZnO NRs using the M-CBD method for different growth times possess better properties than the conventional method under similar deposition conditions. Despite having the highest aspect ratio and growth rate of ZnO NRs, which were found at 4 h growth duration for both methods, the aspect ratio of ZnO NRs using the M-CBD technique was comparatively higher than the conventional CBD method. Besides, the UV PDs fabricated by the M-CBD method at 5 V bias voltage showed high sensitivity, short response time, quick recovery time, high gain, low dark current, and high photocurrent compared with the UV PD device fabricated by the conventional CBD method.

Optimization and characterization of SILAR synthesized ZnO nanorods for UV photodetector sensor

2021-02
Sensors and Actuators A: Physical (Issue : 1) (Volume : 323)
In the current research, zinc oxide (ZnO) nanorods (NRs) have been grown upon glass-slide substrates by employing the effective chemical bath deposition (CBD) method at low-temperature. ZnO seed-layer has been coated over the whole substrates by using very simplicity successive ionic-layer adsorption and reaction (SILAR) approach. The impact of the four different SILAR process cycle for ZnO seed-layer deposition on the characteristic of ZnO NRs have been investigated. The surface morphological, structural, optical properties of the produced ZnO NRs have been studied using several techniques for different SILAR process cycles. Also, the high-quality UV photodetector (PDs) based on ZnO NRs at different SILAR process cycles have been successfully fabricated by applying bias voltage in range of (-5 V to 5 V). The results indicated that the variation of SILAR process cycles have the large and significant impact on the morphological, structural, and optical properties of ZnO NRs. The average size and length of fabricated ZnO NRs were increased with increases the SILAR cycles in the range of 32−98 nm and 291−1210 nm, respectively. The large aspect ratio was noted for ZnO NRs formed at 15 SILAR cycles about 14.93. The growth rate and crystal size of ZnO NRs were increases with increases the SILAR cycles in the range of 1.161–6.722 nm/min and 28.9–94.24 nm/min, respectively. All the samples display a dominant peak at wavenumber of 436.5 cm−1 which is attributed to the E2 active mode and characteristic of the hexagonal phase of ZnO NRs. The energy gap of ZnO NRs was decreased from 3.25 eV to 3.23 eV as the SILAR cycles increases from 5 cycles to 20 cycles. The overall ultraviolet (UV) emission peak centered at 380 nm is found to correlate to near-band emissions (NBE). The ZnO NRs based UV-detector displays repeatable characteristics with a peak photoresponse of 116.6 μA. The UV-sensor based ZnO NRs grown at 15 SILAR process cycles at 5 V bias voltage shows optimal performance responsivity, high photosensitivity, low dark current, quick rise and recovery times were 0.5477 A/W, 3573.57 %, 3.1743 μA, 1.04259 s, and 0.3046 s, respectively.

Synthesis of lead oxide thin films by using physical vapor deposition technique

2021-02
Materials Today: Proceedings
In this study, the lead oxide thin films were synthesized upon the glass slide substrate by using the physical vapor deposition (PVD) technique. The molybdenum boat was used to heat the high purity lead (Pb) powder with 5 × 10−5 mbar vacuum pressure of the PVD chamber. The morphological, structural, and optical properties have been examined and characterized by employing different characterizations techniques. The results found that the crystal size and interplanar distance of lead oxide thin film were about 1.695 nm and 3.55 Å, respectively. The lead oxide thin film has high average transmittance in the visible region which was about (∼80%) and low average transmittance in the UV region. Also, the energy band gap (Eg) of the deposited lead oxide thin film was 2.35 eV.

Effect of Growth Temperature on Morphological, Structural, and Optical Properties of ZnO Nanorods Using Modified Chemical Bath Deposition Method

2021-01
Journal of Electronic Materials
Zinc oxide (ZnO) nanorods (NRs) have been investigated as a function of different growth temperature using modified chemical bath deposition (M-CBD) method. In this study, air bubbles were utilized inside the growth solution as an original modified process. The synthesis of ZnO NRs was carried out through two steps. The first step was deposition of the ZnO seed layer on the glass substrate, while the second step was growing the ZnO NRs on the seeded substrate. The impacts of the growth temperature on the morphology and crystal structure of the ZnO samples were investigated using field emission scanning electron microscopy and x-ray diffraction. UV–Vis spectroscopy was also utilized to characterize the optical properties of the ZnO NRs. The results showed that the growth of the ZnO samples is a NRs-like shape. The ZnO samples possess the hexagonal wurtzite structure with high crystal quality, and no other phases from the impurity were observed. Additionally,the ZnO NRs were found to be well oriented along te (002) planes with diameters ranging from 71 nm to 328 nm and length from 294 nm to 2475 nm, while the aspect ratio was up to 25 with different growth temperatures. However, the UV–Vis spectrum showed that the optical transmittance of the ZnO NRs dropped from ~ 66% to ~ 3.3%, and the absorption band edge had been shifted to a lower-energy region as the growth temperature increased from 65°C to 95°C. This is possibly due to the scattering increase and absorption light from voids, grain size, and thickness of the ZnO NRs. Therefore, it has been demonstrated that the ZnO NRs grown by the M-CBD method at a growth temperature of 95°C gives the most favorable result, since the NRs possess the optimum, homogenous, and uniform distribution with a higher aspect ratio, crystal quality, crystal size, and band gap energy.
2020

Synthesis and Characterizations of ZnO Thin Films Grown by Physical Vapor Deposition Technique

2020-12
JOURNAL OF APPLIED SCIENCE AND TECHNOLOGY TRENDS (Issue : 04) (Volume : 01)
In the current study, Zinc oxide (ZnO) thin films have been synthesized over the whole the glass-slide substrate by utilizing the physical vapor deposition (PVD) technique. The Zinc (Zn) seed layer was deposited by heating the high purity Zn powder by using a molybdenum (Mo) boat at 37.503×10-3 Torr vacuum pressure of the PVD chamber. The ZnO thin films were fabricated by oxidation of the Zn seed layer coated glass-slide substrate at 400 οC. The morphological, chemical compositions, crystal quality, structural and optical properties of fabricated ZnO thin film were characterized and studied utilizing several characterization techniques. The results found that the high distribution density, homogenous, uniform, and high-quality ZnO thin film was grown over the entire substrate. The synthesized ZnO thin film with a thickness of 130 nm was grown with high purity and polycrystalline hexagonal-Wurtzite phase of ZnO. The sharp, and dominant diffraction peak was observed at peak position 34.3375 along (002) plane and c-axis. The investigated crystal size, dislocation density, and interplanar spacing were about 13.33 nm, 5.63×10-5 Å, and 2.609 Å, respectively. Also, UV-visible spectroscopy results show the high transmittance and low absorbance in the visible (Vis.) region and were about 90%, and the transmittance decreases sharply near the UV region at a wavelength around 383 nm. Besides, obtained the energy band-gap (Eg) was about 3.24 eV.

The Influence of Various Reactants in the Growth Solution on the Morphological and Structural Properties of ZnO Nanorods

2020-10
Passer Journal (Issue : 2) (Volume : 2)
In the current work, the effect of three different Zinc (Zn) salts as reactants precursors in the growth solution on the characteristic properties of the Zinc oxide (ZnO) nanorods (NRs) was investigated and reported. High quality hexagonal ZnO NRs have been grown on the glass-slide substrates via the chemical-bath deposition (CBD) approach at 90 ºC. The radio-frequency sputtering (RF) technique has been used to coat the 150 nm of ZnO nano-seed layer over the whole glass-slide substrates. The Field-emission scanning electron microscopy (FESEM), the Energy-dispersive characterization (EDX), and the X-ray diffraction (XRD) characterizations have been used to characterize and examination of the morphological, chemical compositional, and structural characteristics with ZnO hexagonal-wurtzite structure of the NRs. The used zinc salts were Zinc-nitrate Hexahydrate (ZNH), Zinc-acetate (ZA), and Zinc-chloride (ZC). The FESEM and XRD results indicated that the change in types of Zinc salts with Methenamine as reactants precursors in the growth (deposition) solution have a remarkable and significant impact on the surface topography (morphology) characteristics and structural characteristics of synthesized ZnO NRs. The average size and average length of the grown ZnO NRs were in the range of (91-529) nm and (1008-3189) nm, respectively. The high aspect ratio was obtained of ZnO NRs synthesized from Zinc-nitrate Hexahydrate salt and was about 11. The highest growth rate was investigated ZnO NRs synthesized from Zinc-chloride salt and was about 17.716 nm/min. The average crystalline size of synthesized ZnO nanorods was in the range (48.35-56.06) nm

The effect of different substrate-inclined angles on the characteristic properties of ZnO nanorods for UV photodetectors applications

2020-07
Journal of Materials Science: Materials in Electronics
The effect of six different substrate-inclined angle with the vessel on the characteristics properties of the Zinc Oxide (ZnO) nanorods was explored and reported. The vertically well-aligned ZnO Nanorods (NRs) were synthesized on glass substrates by using the low-cost chemical bath deposition (CBD) method at 90 °C. The RF magnetron sputtering has been employed to deposit the ZnO nanoseed layer on glass substrates and electrodes for UV photodetectors (PDs) devices. The morphological, structural, and optical properties of the synthesized ZnO NRs have been investigated using various characterization techniques for different substrate- inclined angles. Also, the high-quality UV photodetector-based ZnO NRs have been fabricated for the optimum substrate-inclined angle of 70° with the vessel by applying a different bias voltage. The results found that variation of substrate-inclined angles have the remarkable and significant effect on the shape, size, length, alignment, density distribution, structure, lattice parameters, crystalline size, energy band gap (Eg), and optical properties of ZnO NRs. The average diameters and length of grown ZnO NRs were in the range of (58–249) nm and (303–2518) nm, respectively. The high aspect ratio, length, and growth rate were observed for ZnO nanorods grown at 70° substrate-inclined angle. The preferred orientation of ZnO NRs was along (002) hexagonal wurtzite plane and the intensity of (002) diffraction peak for ZnO NRs was increased with increasing substrate-inclined angles. The average crystalline size was in range of (46.7–58.8) nm. The average transmittance of ZnO NRs showed a reduction in the range of (44.5–3.3)% as the substrate angle increased. The optical studies show that the synthesized ZnO NRs have the direct Eg in the range of (3.16–3.254) eV. The fabricated UV PD-based ZnO NRs showed high performance and quality. The different bias voltage study shows that the ZnO nanorod UV PD has higher stability and repeatability at 5 V bias voltage. The PDs device exhibited the responsivity value of 3.49903 A/W to 390 nm light wavelength at 5 V, which is higher than those reported for UV PDs-based ZnO NRs. At 5 V bias voltages, the fabricated UV PDs showed a faster response and recovery times of 0.3402 S and 0.1639 S, respectively.

Investigation the Effect of Chemical Composition of Perovskite Layer on Performance of Perovskite Solar Cells

2020-07
Journal of Emerging Technologies and Innovative Research (JETIR) (Issue : 7) (Volume : 7)
In this work, a modest method for creating Perovskite solar cells (PSCs) by recycling car batteries is used. Trying to get rid of some structures or materials which are harm to the environment. However, by reusing car batteries we will avoid the disposal of toxic battery materials and provide an alternative technique, readily-available Pb source for fabricating PSCs. Perovskite solar cells (PSCs) were prepared by two-step spin coating solution method on the FTO glass substrate. Lead iodide (PbI2) and methyl-ammonum iodide (CH3NH3I) used to form the structure of the precursor (CH3NH3PbI3). The photovoltaic performance of PSCs and the effect of chemical composition of perovskite layer on performance of PSCs was investigated. Characterization of PSCs by using X-ray diffraction, SEM and the effect of chemical composition on of MAPI films was achieved. It was found that the thickness ratio of (PbI2/MAI) with 3.0:1 have highest fill factor and maximum efficiency.

STUDY THE OPTICAL PROPERTIES OF THE VARIOUS DEPOSITION SOLUTIONS OF ZnO NANORODS GROWN ON GLASS SUBSTRATE USING CHEMICAL BATH DEPOSITION TECHNIQUE

2020-06
Journal of Ovonic Research (Issue : 3) (Volume : 16)
In this study, two-step chemical bath deposition (CBD) technique has been employed for the fabrication of Zinc Oxide (ZnO) nanorods at low temperature. The ZnO nano-seed layer was deposited on the glass substrate using a radio frequency sputtering discharge technique. The impact of three zinc salts with Hexamethylenetetramine (HMTA) on the properties of ZnO nanorods have been investigated. The double beam UV visible (UV4100) spectrometer, micro-Raman scattering, and Field emission scanning electron microscopy (FESEM) were used to characterize and study the optical properties, energy band gap, defects, Raman spectra, phase orientation, quality of material, the interaction of phonons, transport properties, and the morphology of synthesized ZnO nanorods (NRs), respectively. The three zinc salts are Zinc Nitrate Hexahydrate, Zinc Acetate, and Zinc Chloride. The results found that the variation in zinc salts types with Hexamethylenetetramine as deposition solution is play a very important impact on the structures of fabricated ZnO nanorods that effected directly on the optical properties, energy band, material quality, and phase orientation of ZnO NRs. Also, from UV measurement the optical properties and energy band gap of produced ZnO nanorods are changed with changing the zinc salt as a precursor of deposition solution.

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

2020-06
Current Organic Synthesis (Issue : 3) (Volume : 17)
The study aimed at synthesizing ZnO nanoparticles by using Petroselinum crispum extract, commonly known as parsley, as a source of biosynthesis without utilizing chemical agents for reducing, capping, and stabilizing agent.

Enhancement of ZnO Nanorods Properties Using Modified Chemical Bath Deposition Method: Effect of Precursor Concentration

2020-05
Crystals (Issue : 5) (Volume : 10)
In this study, the effects of different precursor concentrations on the growth and characteristics properties of the zinc oxide (ZnO) nanorods (NRs) synthesized by using modified and conventional chemical bath deposition (CBD) methods were investigated. The morphologic, structural and optical properties of synthesized ZnO NRs with different precursor concentrations were studied using various characterization techniques. The experimental results show that the varying precursor concentration of the reactants has a remarkable and significant effect on the growth and characteristics properties of ZnO NRs. In addition, the characteristic properties of ZnO NRs grown using the modified method showed significantly improved and enhanced properties. The average length of grown ZnO NRs increased with increased precursor concentration; it can be seen that longer ZnO NRs have been investigated using the modified CBD methods. The ZnO NRs synthesized at 0.05 M using the modified method were grown with high aspect ratios than the ZnO NRs grown using conventional means which were 25 and 11, respectively. The growth rate increased with increased precursor concentration; it can be observed that a higher growth rate was seen using the modification CBD method. Furthermore, XRD results for the two cases reveal that the grown ZnO samples were a nanorod-like in shape and possessed a hexagonal wurtzite structure with high crystal quality. No other phases from the impurity were observed. The diffraction peaks along (002) plane became higher, sharper and narrower as precursor concentration increased, suggesting that the crystalline quality of ZnO NRs grown using the modified method was more enhanced and better than conventional methods. However, optical studies show that the transmittance at each concentration was more than two times higher than the transmittance using the modified CBD method. In addition, optical studies demonstrated that the ZnO NRs grown by using modified and conventional methods had a direct Eg in the range of (3.2–3.26) eV and (3.15–3.19) eV, respectively. It was demonstrated in two methods that ZnO NRs grown at a precursor concentration 0.05 M gave the most favorable result, since the NRs had best characteristic properties.

SYNTHESIS OF RUTILE-TiO2 NANOROD ARRAYS FOR EFFICIENT SOLAR WATER SPLITTING VIA MICROWAVE-ASSISTED HYDROTHERMAL METHOD

2020-03
Digest Journal of Nanomaterials and Biostructures (Issue : 1) (Volume : 15)
Using a microwave-assisted ‎hydro thermal method (MWAHM) a single crystalline of vertically aligned TiO nanorod (NR) ‎arrays has been achieved via the novel ultra-rapid synthetic ‎method for the production. High-quality NR arrays with ‎controlled film thickness were achieved with fine control of the ‎growth conditions as well. The effect of the different reaction conditions of ‎MWAHM such as reaction time and growth temperature on the ‎morphology, crystal orientation, and photo catalytic activity have ‎been systematically investigated. In a typical condition of the ‎MWAHM using 0.4 cm 2 of titanium(IV) n-butoxide (TBO) at ‎‎180 °C for 40 minutes, a small diameter of 124 nm and short length ‎‎2.93 µm of TiO 2 nanorods, are grown on fluorine-doped tin oxide (FTO) substrate. However, the photo current ‎density produced TiO2 NRs of 2.90 mA cm with a maximum ‎photo conversion efficiency of about 2.7% which confers excellent ‎photoelectrochemical performance. In comparison with the typical ‎hydro thermal method (HM) synthesized NRs, the ultra-fast ‎MWAHM synthesized NRs offers five times more efficiency ‎photoelectrochemical (PEC) water splitting than the hydro thermal ‎method (HM).‎‎The results suggest that these dense and aligned one-dimensional ‎TiO2 nanorods are promising for hydrogen generation from water ‎splitting based on PEC cells.
2018

INVESTIGATION OF OPTICAL PROPERTIES OF ZnO NANORODS GROWN ON DIFFERENT SUBSTRATES

2018-12
Science Journal of University of Zakho (Issue : 4) (Volume : 6)
ZnO nanorods arrays are synthesized over the different substrates namely; Indium Tin Oxide (ITO), Kapton Tape (KT), Polyethylene terephthalate (PET), Porous Silicon (PS) and Silicon (Si) using modified chemical bath deposition (MCBD) method at 95 ºC for 4 h. The MCBD is the air bubbles inside growth solution during CBD process. The ZnO nano-seed layers are coated on different substrates using RF magnetron sputtering technique. The optical properties (transmittance, reflectance and energy band gap) and surface morphology of ZnO nanorods grown on different substrates have been investigated in details by using UV-Visible Spectrometer and Field emission scanning electron microscopy (FESEM), respectively. The results found that the morphology and diameter of ZnO nanorods is closely concerned with the nature of substrates. Also it is indicated that the substrate has strong and important impact on the growth, optical properties, Eg and quality of synthesized ZnO nanorods (NRs). The higher transmittance has been observed for ZnO NRs grown over KT substrates and is about (~ 33 %). The average transmittance decreases sharply near UV region at wavelength around 393 nm for ZnO nanorods grown on ITO substrate. However, for PET and KT substrates, the transmittance decreases sharply near visible region around 401nm and 498 nm, respectively. Besides, the ZnO NRs grown on PS substrate have the strong reflectance characteristics after approximately 395 nm, and then decreases in the wavelength range of 410 nm to 700 nm. On the other hand, the strong reflectance property of ZnO NRs grown on Si substrate is observed at 400 nm. Also, the minimum and maximum Eg are obtained for ZnO nanorods that fabricated on the KT substrate and porous silicon substrate, respectively.
2017

EFFECT OF THE GROWTH TIME ON THE OPTICAL PROPERTIES OF ZNO NANORODS GROWN BY LOW TEMPERATURE METHOD

2017-10
Digest Journal of Nanomaterials and Biostructures (Issue : 4) (Volume : 12)
ZnO nanorods have been synthesized on glass substrate by low-cost two step chemical bath deposition (CBD) method at low temperature. The ZnO seed layers have been coated on glass substrate by RF magnetron techniques with power 150 watt for 15 min. The influence of different growth time on the optical properties, energy band gap, Raman spectra and surface morphology of ZnO nanorods are investigated. The growth time are (0.5, 1, 2, 3, 4 and 5) h. The double beam UV visible (UV-5000) , Raman Spectroscopy and field emission scanning electron microscopy have been used to characterize the optical properties (absorption and transmission), energy band gap, Raman spectra, surface morphology, diameter, distribution and homogeneity of produced ZnO nanorods. The results found that the growth time have significant effect on the optical properties, energy band gap, Raman modes, aligned, surface morphology, diameter, ZnO distribution and density. And It is observed that the absorbance of the growth times 4 and 5 h are higher than the other growth times of ZnO nanorods, which showed the good crystallinity of the other samples. The transmittance decreases sharply near UV region at wavelength around 385 nm due to the optical band gap absorption.The obtained energy band gap of ZnO nanorods decreases with increase in the growth time from 3.25 eV to 3.18 eV. From result, it was investigated that the growth time caused the average crystalline size increases and decreases defects causing the energy band gap decreased. From Raman spectra , it observed that the dominant and sharp peaks at approximately 100 cm-1c and 437 cm forthe ZnO nanorods grown of 4 h and 5 h as a growth times, which are corresponds to the intrinsic characteristics of the Raman active E2(low) and E modes of the hexagonal wurtzite ZnO, respectivly Also FESEM results shows that the growth time has a good playing role on the nanostructure growth orientation of the ZnO nanorods.

Fabrication, characterization of ZnO nanorods on the flexible substrate (Kapton tape) via chemical bath deposition for UV photodetector applications

2017-08
AIP Conference Proceedings, International Conference on Applied Physics and Engineering (ICAPE2016) (Issue : 020004) (Volume : 1875)
One dimensional ZnO nanorods have been synthesized on flexible substrate. The substrate is Kapton Tape (KT). ZnO Nanorods are produced by using low cost chemical bath deposition method at low temperature. The investigation of the effect of substrate on the morphological, elementary composition, structural characteristics and Raman spectroscopy of ZnO nanorods has been done. Field emission scanning electron microscopy (FESEM), Energy Dispersive analysis (EDX), X-ray diffraction (XRD) and Raman spectroscopy measurements are employed to examine the morphological, compositional and structural haracteristics with hexagonal wurtzite structure of the ZnO nanorods arrays. The results found that the average diameter of ZnO nanorods is found to be closely related to the substrate nature. It is concluded that the substrate can effect on the ZnO nanorods growth remarkably and the selective growth of ZnO nanorods is possible through the choice of the substrate. The crystallite size and the lattice constants of the synthesis ZnO nanorods are obtained based on the XRD data. The found results revealed that the increase in the crystallite size is strongly associated with the type of substrate.

THE INFLUENCE OF THE GROWTH TIME ON THE SIZE AND ALIGNMENT OFZnO NANORODS

2017-03
Science Journal of University of Zakho (Issue : 1) (Volume : 5)
Vertically aligned ZnO nanorods arrays were synthesized on glass substrates. ZnO seed layers were prepared on glass substrate by RF Sputtering technique. ZnO nanorods synthesized using low-cost chemical bath deposition method at low temperature (95 ºC). The effect of the different growth time such as (0.5, 1, 2, 3, 4 and 5) h on the morphology, elemental chemical composition and structure of the ZnO nanorods were obtained systemically, and tested by Field emission scanning electron microscopy (FESEM), Energy dispersive analysis (EDX), and XRD measurements. The results found that the ZnO nanorods with hexagonal wurtzite structure grow vertically on the glass substrates. Most of the prepared samples have strong and sharp (002) peak intensities and the diffraction peaks (002) become higher and narrower as growth time increasing, obtaining that the ZnO crystalline quality became better with growth time increasing. The growth rate was decreases with increasing growth time, and the high aspect ratio was found at 4 h as a growth time. The size, length and crystalline size of the ZnO nanorods increase with increasing growth time. Furthermore the ZnO nanorods vertically grow at (002) direction along the c-axis on the glass substrate, with elementary chemical compositions of zinc and oxygen only for all prepared samples.
2016

NOVEL PROCESS USING OXYGEN AND AIR BUBBLING IN CHEMICALBATH DEPOSITION METHOD FOR VERTICALLY WELL ALIGNED ARRAYS OF ZnO NANORODS

2016-10
Digest Journal of Nanomaterials and Biostructures (Issue : 4) (Volume : 11)
Vertically well-aligned ZnO nanorods arrays have been synthesized on ZnO seed layer coated glass substrates at low temperature using modified low-cost chemical bath deposition (CBD) method. The investigation of the influence of no air bubbles, air bubbles and oxygen bubbles inside the CBD reactor on the structural characteristics, morphological (diameter, length, aligned, distribution and homogeneously), elements chemical composition and optical properties of ZnO nanorods have been studied. This new modification of chemical bath deposition method shows the improved results over traditional chemical bath deposition method. The important results of this novel process are the good morphological, structural characteristic and optical properties of ZnO nanorods. These results obtained in just of 3.5 h growing time in the CBD reactor. On this modified CBD the growth time rate decreases about 1.5 h compared with the previous works.

DIFFERENT SUBSTRATES EFFECTS ON THE TOPOGRAPHY AND THE STRUCTURE OF THE ZnO NANORODS GROWN BY CHEMICAL BATH DEPOSITION METHOD

2016-09
Digest Journal of Nanomaterials and Biostructures (Issue : 3) (Volume : 11)
In this paper, vertically aligned ZnO nanorods arrays were fabricated on different substrates. The substrates are Indium Tin Oxide (ITO) coated glass, polyethylene terephthalate (PET), Silicon (Si), Porous Silicon (PS) and Kapton Tape (KT). Nanorods are fabricated at low temperature by using chemical bath deposition method. The investigation of the effect of substrates on the morphological, elementary composition and structural characteristics of ZnO nanorods has been done. Field emission scanning electron microscopy (FESEM), Energy Dispersive analysis (EDX) and X-ray diffraction (XRD) measurements were used to investigate the morphological, compositional and structural characteristics with hexagonal wurtzite structure of the ZnO nanorods arrays. The average diameter of ZnO nanorods are found to be closely related to the substrates nature. It is concluded that the substrates can effect on the ZnO nanorods growth remarkably and the selective growth of ZnO nanorods is possible through the choice of the substrates. The crystallite size and the lattice constants of the synthesis ZnO nanorods were calculated based on the XRD data. The found results revealed that the increase in the crystallite size is strongly associated with the type of substrate.
2013

Theoretical and Experimental Investigation of Hollow Cathode Nitrogen Glow Discharge Plasma

2013-06
Digest Journal of Nanomaterials and Biostructures (Issue : 12) (Volume : 7)
An experimental investigation of a DC hollow cathode nitrogen glow discharge has been done at different gas pressure ranged from (0.075 to 0.75) torr and different radial positions of discharge. Plasma properties were inferred from the current – voltage characteristics of the double probes positioned at different radial space of the discharge, moreover a computer program proposed to determine plasma parameters from the probe characteristics. Furthermore these parameters were calculated using the relation that electron temperature can be written as an explicit function of gas pressure and radius discharge at the Schottky limit. The result exhibits that the measured and calculated electron temperature varies nearly a decreasing exponential with gas pressure as a results of fitting , as well as the variations of both floating and plasma potentials close to the same behavior. On the other hand there is a good agreement between measured and calculated results, these in turn compared with reported works in previous studies and there is a satisfactory agreement.

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