Hydroquinone Sensor Based on Neodymium (Nd) Doped ZnO Hexagonal Nanorods

2018 ◽  
Vol 10 (3) ◽  
pp. 351-357 ◽  
Author(s):  
Yas Al-Hadeethi ◽  
Ahmad Umar ◽  
Ahmed A. Ibrahim ◽  
Rajesh Kumar ◽  
Saleh. H. Al-Heniti ◽  
...  
Keyword(s):  
Dynamic Range ◽  
Hexagonal Phase ◽  
Zno Nanorods ◽  
High Sensitivity ◽  
X Ray Diffraction ◽  
Raman Scattering Spectroscopy ◽  
Morphological Studies ◽  
Wurtzite Hexagonal Phase ◽  
Doped Zno ◽  
Hexagonal Nanorods

Herein, we report a simple hydrothermal synthesis and detailed characterizations of Nd-doped ZnO pointed hexagonal nanorods by various techniques such as field emission scanning electron microscopy (FESEM) attached with energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), UV-visible, Fourier transform infrared (FTIR) and Raman-scattering spectroscopy. The morphological studies revealed pointed hexagonal nanorods arranged in flower-shaped morphologies and well-crystalline with the wurtzite hexagonal phase. The Nd-doped ZnO nanorods were used as potential scaffold to fabricate high sensitivity hydroquinone sensor which exhibited sensitivity of ∼7.43 μA·mM–1cm–2 with a linear dynamic range of (LDR) of 0.313 mM–2.5 mM and correlation coefficient (R2) of 0.99671. The detection limit of Nd-doped ZnO pointed hexagonal nanorods based hydroquinone sensor was found to be 0.313 mM.

Temperature-dependent heterojunction device characteristics of n-ZnO nanorods/p-Si assembly

2020 ◽  
Vol 10 (1) ◽  
pp. 29-36
Author(s):  
Rashad I. Badran ◽  
Yas Al-Hadeethi ◽  
Ahmad Umar ◽  
Saleh H. Al-Heniti ◽  
Bahaaudin M. Raffah ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Hexagonal Phase ◽  
Zno Nanorods ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
Different Temperatures ◽  
Evaporation Technique ◽  
Wurtzite Hexagonal Phase ◽  
Heterojunction Device ◽  
Increasing Temperature

Heterojunction diode based on n-ZnO nanorods/p-Silicon (Si) assembly was fabricated, examined and reported here. Horizontal quartz tube thermal evaporation technique was used for the growth of ZnO nanorods on Si substrate. The nanorods were characterized by several techniques to examine the structural, morphological, scattering and electrical properties. Wurtzite hexagonal phase of the grown aligned nanorods was observed using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The appearance of a sharp Raman peak at 438 cm–1 was observed and it is related to the E2(high) mode of the wurtzite hexagonal phase of ZnO. The electrical properties of the fabricated heterojunction assembly were examined at different temperatures (298∼398 K) in both reverse and forward biased conditions, and a good stability was observed over the entire temperature range. A reduction in the turn-on and breakdown voltage was observed with increasing temperature. By increasing the temperature, the effective potential barrier height was increased, while quality factor was decreased. The observed activation energy was found to be ∼93.4 meV, higher than the exciton binding energy of ZnO.

Fabrication, characterization and magnetic properties of Na-doped ZnO nanorods

2016 ◽  
Vol 09 (03) ◽  
pp. 1650039 ◽  
Author(s):  
Jingyuan Piao ◽  
Li-Ting Tseng ◽  
Kiyonori Suzuki ◽  
Jiabao Yi
Keyword(s):  
Magnetic Measurements ◽  
Zno Nanorods ◽  
X Ray Diffraction ◽  
Paramagnetic Resonance ◽  
X Ray ◽  
Shallow Donors ◽  
Na Doping ◽  
Transmission Electron ◽  
Doped Zno ◽  
Electron Paramagnetic

Na-doped ZnO nanorods have been fabricated through a hydrothermal method. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses indicate that the d spacing of ZnO increases with increasing doping concentration, suggesting the effective incorporation of dopant Na in the samples. Electron paramagnetic resonance (EPR) measurements indicate that there are shallow donors in pure ZnO samples and the shallow donors are strongly prohibited by Na doping. In addition, the resonance at g = 2.005 suggests the formation of Zn vacancies. Magnetic measurements indicate that pure ZnO is paramagnetic and Na doping leads to ferromagnetism at room temperature. Moreover, 0.5% Na-doped ZnO nanorods exhibits the largest saturation magnetization.

PERFORMANCE OF pH SENSOR ELECTRODE BASED ON ZnO NRs ON FTO-GLASS SUBSTRATE

2020 ◽  
Vol 27 (08) ◽  
pp. 1950198
Author(s):  
ABDULQADER D. FAISAL ◽  
MOHAMMAD O. DAWOOD ◽  
HASSAN H. HUSSEIN ◽  
KHALEEL I. HASSOON
Keyword(s):  
Seed Layer ◽  
Zno Nanorods ◽  
Ph Sensor ◽  
High Sensitivity ◽  
Hydrothermal Growth ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zno Nanocrystals ◽  
Electrode Cell ◽  
Fto Glass

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).

Synthesis of Aligned ZnO Hexagonal Nanorods and Its Application to ZnS Based DC Electroluminescent Devices

2003 ◽  
Vol 799 ◽  
Author(s):  
Takashi Hirate ◽  
Hironori Tanaka ◽  
Shinya Sasaki ◽  
Makoto Ozawa ◽  
Weichi Li ◽  
...  
Keyword(s):  
Zno Nanorods ◽  
Deposition Method ◽  
X Ray Diffraction ◽  
High Luminance ◽  
Electroluminescent Devices ◽  
X Ray ◽  
Cvd Method ◽  
Electron Beam Deposition ◽  
Hexagonal Nanorods ◽  
Beam Deposition

ABSTRACTHighly oriented ZnO nanorods have been grown on p--Si(111) wafers using a low-pressure thermal CVD method. X-ray diffraction shows that the nanorods are grown with the c-axis normal to the substrate. An electroluminescent device with ITO/ZnS:Mn/nanorod-ZnO/p--Si structure where the ZnS:Mn and ITO layers are deposited by the electron beam deposition method on the ZnO nanorods layer operates stably in DC mode with high luminance.

Highly Sensitive Picric Acid Chemical Sensor Based on Samarium (Sm) Doped ZnO Nanorods

2019 ◽  
Vol 19 (6) ◽  
pp. 3637-3642 ◽  
Author(s):  
Yas Al-Hadeethi ◽  
Ahmad Umar ◽  
Kulvinder Singh ◽  
Ahmed A Ibrahim ◽  
Saleh. H Al-Heniti ◽  
...  
Keyword(s):  
Large Scale ◽  
Chemical Sensor ◽  
Limit Of Detection ◽  
Picric Acid ◽  
Zno Nanorods ◽  
Hydrothermal Process ◽  
High Sensitivity ◽  
Highly Sensitive ◽  
Doped Zno ◽  
Facile Hydrothermal Process

Herein, we report the synthesis, characterization and picric acid chemical sensing application of samarium (Sm) doped ZnO nanorods. The Sm-doped ZnO nanorods were synthesized by facile hydrothermal process and characterized using various analytical methods which confirmed the large-scale synthesis and wurtzite hexagonal crystal structure for the synthesized nanorods. The doping of Sm ions in the lattices of the synthesized nanorods was evaluated by the energy dispersive X-ray spectroscopy (EDS). The synthesized Sm-doped ZnO nanorods were used as potential scaffold to fabricate high sensitive and reproducible picric acid chemical sensor based on I–V technique. The fabricated picric acid chemical sensor based on Sm-doped ZnO nanorods exhibited a high sensitivity of 213.9 mA mM−1 cm−2 with the limit of detection of ∼0.228 mM and correlation coefficient of R═0.9889. The obtained results revealed that the facile grown Sm-doped ZnO nanorods can efficiently be used to fabricate high sensitive and reproducible chemical sensors.

Influence of Al, Ta Doped ZnO Seed Layer on the Structure, Morphology and Optical Properties of ZnO Nanorods

2019 ◽  
Vol 4 (1) ◽  
pp. 45-58
Author(s):  
S. Mageswari ◽  
Balan Palanivel
Keyword(s):  
Zinc Oxide ◽  
Optical Properties ◽  
Band Gap ◽  
Seed Layer ◽  
Hexagonal Phase ◽  
Zno Nanorods ◽  
Oxide Material ◽  
Vertically Aligned ◽  
Doped Zno ◽  
Seed Layers

Background: Zinc oxide (ZnO) is one of the most attractive II-VI semiconductor oxide material, because of its direct wide band gap (3.37 eV) and large binding energy (60 meV). Zinc oxide (ZnO) is a promising semiconductor due to its optimised optical properties. Among semiconductor nanostructures, the vertically aligned one-dimensional ZnO nanorods are very important for nano device application. Methods: Vertically aligned ZnO nanorod arrays were grown on ZnO, aluminum doped ZnO (ZnO:Al), tantalum doped ZnO (ZnO:Ta) and aluminum and tantalum co-doped ZnO (ZnO:Al,Ta) seed layer by hydrothermal method. Results: The X-Ray Diffraction (XRD) investigation indicated the presence of hexagonal phase for the both seed layers and nanorods. The Scanning Electron Microscope (SEM) images of ZnO and doped ZnO seed layer thin-films show spherical shaped nanograins organized into wave like morphology. The optical absorption spectra revealed shift in absorption edge towards the shorter wavelength (blue shifted) for ZnO nanorods grown on ZnO:Al, ZnO:Ta and ZnO:Al,Ta seed layer compared to ZnO nanorods grown on ZnO seed layer. Conclusion: The increase in band gap value for the ZnO nanorods grown on doped ZnO seed layers due to the decrease in crystallite size and lattice constant as evidenced from XRD analysis. The unique property of Al, Ta doped ZnO can be used to fabricate nano-optoelectronic devices and photovoltaic devices, due to their improved optical properties.

Co-Doped ZnO Nano-Agglomerates as a Potential Scaffold for Non-Enzymatic Hydrogen Peroxide Sensing

2021 ◽  
Vol 13 (9) ◽  
pp. 1732-1738
Author(s):  
Ahmad Umar ◽  
Ramesh Kumar ◽  
Rajesh Kumar ◽  
Ahmed A. Ibrahim ◽  
Mohsen A. M. Alhamami ◽  
...  
Keyword(s):  
Hexagonal Phase ◽  
Average Particle Size ◽  
Solution Process ◽  
Average Particle ◽  
Spherical Nanoparticles ◽  
Cyclic Voltammetric ◽  
Wurtzite Hexagonal Phase ◽  
Dynamic Concentration ◽  
Doped Zno ◽  
Co Doped

Co-doped ZnO nano-agglomerates were synthesized by a facile solution process. Several characterization techniques revealed the successful doping of the ZnO by Co ions. FESEM results showed the agglomeration of the Co-doped ZnO nanoparticles to form large-sized nano-agglomerates. The diameters of the spherical nanoparticles and the agglomerates were not found to be uniform. The diameters of the nano-agglomerates ranged from ~25 nm–120 nm. XRD spectrum confirmed the Wurtzite hexagonal phase of ZnO in Co-doped ZnO nanoagglomerates. The average particle size for Co-doped ZnO nano-agglomerates was 20.68 nm. The sensing parameters were examined by using Co-doped ZnO nano-agglomerates modified gold electrode through cyclic voltammetric and amperometric analysis. The sensitivity of 70.73 μAmM−1cm−2 and very low-detection limit of 0.2 μM was observed for H2O2. The corresponding linear dynamic concentration range was 0.2–1633 μM. The excellent sensing activities of the Co-doped ZnO nano-agglomerates for H2O2 were attributed to the improved intrinsic electric properties and increased inner defects density, particularly near the interface region.

Preparation and Optical Property of Mn-Doped ZnO Nanorods

2011 ◽  
Vol 189-193 ◽  
pp. 643-647
Author(s):  
Chuan Sheng Chen ◽  
Tian Gui Liu ◽  
Liang Wu Lin ◽  
Xi Li Xie ◽  
Zhen Wu Ning ◽  
...  
Keyword(s):  
Optical Property ◽  
Sol Gel ◽  
Zno Nanorods ◽  
Blue Emission ◽  
X Ray Diffraction ◽  
Uv Emission ◽  
Transmission Electron ◽  
Doped Zno ◽  
Electron Microscopes ◽  
Mn Doped

Mn-doped ZnO (Zn0.97Mn0.03O) nanorods were synthesized by sol-gel method combined with subsequent heat treatment. The structure and optical property of Mn-doped ZnO nanorods were studied by x-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), and fluorescence. The results of electron microscopes illuminate that the Zn0.97Mn0.03O nanorods are prepared at calcinations of 450 under the protection of nitrogen. The Zn0.97Mn0.03O nanorods are composed of small particles of size 20–30 nm. Fluorescence spectra of Zn0.97Mn0.03O nanorods exhibit that there are two very strong blue emission peaks at 451 nm and 461nm except a strong UV emission at 396 nm.

Novel Synthesis of Nanorod ZnO and Fe-Doped ZnO by the Hydrolysis of Metal Powders

2007 ◽  
Vol 7 (11) ◽  
pp. 4158-4160 ◽  
Author(s):  
B. S. Han ◽  
Y. R. Uhm ◽  
G. M. Kim ◽  
C. K. Rhee
Keyword(s):  
Wave Length ◽  
Zno Nanorods ◽  
Fe Doping ◽  
Metal Powders ◽  
Resolution Limit ◽  
X Ray Diffraction ◽  
Fe Content ◽  
Doped Zno ◽  
Diffraction Patterns ◽  
Hydrolysis Of

Fe-doped ZnO nanorods have been synthesized by a novel process employing a hydrolysis of metal powders. Zn and Fe nano-powders were used as starting materials and incorporated into distilled water. The solution was refluxed at 60 °C for 24 h to obtain the precipitates from the hydrolysis of Zn and Fe. X-ray diffraction patterns for all the samples showed a pure wurtzite single phase, without any segregation of the Fe into the particulates within the instrumental resolution limit. The TEM results for ZnO with and without an Fe-doping showed that the produced powders had a rod-like shape. The rod shape was attributable to the zinc oxide from the hydrolysis of Zn. With an increasing Fe content, the UV–vis spectra were shifted to a long wave length and this result indicates that the band gap was changed by an Fe-doping.

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