The Influence of the Growth Time on the Size and Alignment of Zno Nanorods

et al. 2020

Crystals

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.

Section: Growth Processmentioning

confidence: 99%

“…The inter planer distance of the hexagonal wurtzite structure of synthesized ZnO NRs along (002) peak was calculating by using Bragg's law [43], and its results are summarized in Tables 1 and 2 for the two fabrication methods. 1…”

Section: The Structural Properties and Lattice Parametersmentioning

confidence: 99%

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

Abdulrahman

et al. 2020

Crystals

“…The crystal structure of the undoped (pure) ZnO nanorods prepared by CBD is shown in figure (2a). It can be notice that ZnO nanorods have hexagonal structure, remarkably sharp peak at 2θ =34.3750, which is assigned to be the (002) peak of hexagonal structure and with (FWHM) is 0.7872, and this is meaning that the most ZnO nanorods are grown along c-axis (26) . Figure (2b) (27) .…”

Section: Resultsmentioning

confidence: 95%

Characterization of Al-doped ZnO nanorods grown by chemical bath deposition method

2018

Innovaciencia

SCIENTIFIC RESEARCHHow to cite this paper: Ahmed, Sabah, M., Characterization of Aldoped ZnO nanorods grown by chemical bath deposition method, Duhok, Iraq. Innovaciencia. 2018; 6(1): 1-9. http://dx. ABSTRACT Introduction:In recent years a metal oxide semiconductors have been paid attention due to their excellent chemical and physical properties. ZnO (Zinc oxide) is considered as one of the most attractive semiconductor materials for implementation in photo-detectors, gas sensors, photonic crystals, light emitting diodes, photodiodes, and solar cells, due to its novel electrical and optoelectronic properties. There are different uses of metal oxide semiconductors such us, UV photodetectors which are useful in space research's, missile warning systems, high flame detectors, air quality spotting, gas sensors, and precisely calculated radiation for the treatment of UV-irradiated skin. ZnO is a metal oxide semiconductors and it is used as a transparent conducting oxide thin film because it has the best higher thermal stability, best resistance against the damage of hydrogen plasma processing and relatively cheaper if one compares it with ITO. Materials and Methods: On glass substrates, Al-doped ZnO (AZO) nanorods have been grown by a low -cost chemical bath deposition (CBD) method at low temperature. The seed layer of ZnO was coated on glass substrates. The effect of the Al-doping on the aligned, surface morphology, density, distribution, orientation and structure of ZnO nanorods are investigated. The Al-doping ratios are 0%, 0.2%, 0.8% and 2%. The Aluminum Nitrate Nonahydrate (Al (NO3)3.9H2O) was added to the growth solution, which is used as a source of the aluminum dopant element. The morphology and structure of the Al-doped ZnO nanorods are characterized by field emission scanning electron microscopy (FESEM) and high-resolution X-ray diffractometer (XRD). using the radio RF (Radio frequency) magnetron technique. Results and Discussion: The results show that the Al-doping have remarkable effects on the topography parameters such as diameter, distribution, alignment, density and nanostructure shape of the ZnO nanorods. These topography parameters have proportionally effective with increases of the Al-doping ratio. Also, X-ray diffraction results show that the Al-doping ratio has a good playing role on the nanostructure orientation of the ZnO nanorods. Conclusions: The Aluminum Nitride Nanohydrate considered as a good Aluminum source for doping ZnONR. It is clear from FESEM results that the Al-doping of ZnONR has a remarkable effect on the surface topography of nanorods for all aluminum doping ratios. From XRD patterns, it concludes that as the Al-doping ratio increases, the reorientation of the nanostructure of ZnO increases towards [100] direction. The results obtained also have shown that the average diameter of a nanorod is increased with increasing the ratio of Al-doping.

“…The microscopic glass slide was employed as the substrates for zinc oxide thin film deposition. Before the deposition process of ZnO thin film, the glass substrates were prepared with a dimension of (25×75×1) mm 3 . The glass-slide substrates were cleaned by soaking the glass substrates in the solution of in Chromic Acid (H2CrO4) for 1 day, and then taken off from the acid solution and rinsed with distilled water, and Ethanol (C2H5OH) for 15 min, respectively.…”

Section: Methodsmentioning

confidence: 99%

“…Recently, many scientists and researchers have been extensively studied and worked on the wide energy gap semiconductor materials includes ZnO due to their excellent properties and uses in optoelectronic (OPE) devices [2]. The ZnO has a hexagonal wurtzite structure and direct optical energy gap which is 3.37 eV at room temperature (RT) [3][4][5][6]. At RT, the ZnO has the wider and larger exciton binding energy which is 60 meV compared to the Gallium Nitrate (GaN) which is (20 meV) [4,7].…”

Section: Introductionmentioning

confidence: 99%

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

Mohammed

Abdulrahman

et al. 2020

JASTT

Self Cite

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 °C. 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 A°, and 2.609 A°, 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.