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).

The Effect of Cooling Rate During the Hydrothermal Growth on the Tip Geometry of ZnO Nanorods

2012 ◽  
Vol 602-604 ◽  
pp. 144-147
Author(s):  
He Qiu Zhang ◽  
Xiu Ming Ren ◽  
Li Zhong Hu ◽  
Jiu Yu Ji ◽  
Yang Li ◽  
...  
Keyword(s):  
Cooling Rate ◽  
Hexagonal Phase ◽  
Zno Nanorods ◽  
Critical Factor ◽  
Hydrothermal Growth ◽  
Water Cooling ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cooling Conditions ◽  
Structural Characterizations

The ZnO nanorods with sharp tip have been fabricated via water cooling treatment during the hydrothermal growth. The morphology and crystal structure of the zinc oxide nanostructure were examined by field-emission scanning electron microscopy and x-ray diffraction, respectively. The structural characterizations revealed that the as-synthesized nanorods were single crystalline, with a hexagonal phase. It has been demonstrated that the cooling rate is the critical factor of the synthesis of the sharp tip ZnO nanorods by comparing the different cooling conditions. The growth mechanism for the sharp tip ZnO nanorods has been proposed on the basis of the different crystallographic habits of wurtzite hexagonal ZnO crystals.

Hydrothermal Growth of ZnO Nanorods along the Ultra-Thin ZnO Seed Layer Prepared by Magnetron Sputtering

2016 ◽  
Vol 675-676 ◽  
pp. 130-133
Author(s):  
Wissawat Sakulsaknimitr ◽  
Kanyakorn Teanchai ◽  
Mati Horprathum ◽  
Chanunthorn Chananonnawathorn ◽  
Saksorn Limwichean ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Seed Layer ◽  
Treatment Process ◽  
Zno Nanorods ◽  
Annealing Treatment ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron ◽  
Seed Layers

ZnO nanorods were grown on magnetron sputtered ultra-thin ZnO seed layers through a hydrothermal method. Before ZnO nanorods growth, the ultra-thin ZnO seed layer has been annealed at temperatures ranging from 100 to 400°C in air. The influence of annealing treatment on the crystalline structure of the ultra-thin ZnO seed layers has been investigated by X-ray diffraction (XRD). The size and density of final prepared ZnO nanorods were investigated by field-emission scanning electron microscopy (FE-SEM). It was found that the length and the aspect ratio of the ZnOnanorods can be readily tuned by control of the ZnO ultra-thin seeds layer which results from the annealing treatment process.

Fabrication of ZnO Nanorods on Silicon Substrates by Sol-gel Hyrdothermal Methods

2015 ◽  
Vol 18 (2) ◽  
pp. 083-086
Author(s):  
Yow-Chyun Shyu ◽  
Min Han Lin ◽  
Shang-Ren Lin ◽  
Shang Lin Tsai ◽  
Chin Pang Chen ◽  
...  
Keyword(s):  
Seed Layer ◽  
Sol Gel ◽  
Zno Nanorods ◽  
Silicon Substrates ◽  
Photoluminescence Spectra ◽  
X Ray Diffraction ◽  
X Ray ◽  
Growth Orientation ◽  
Multiple Material ◽  
Hydrothermal Methods

ZnO nanorods were deposited on silicon substrate using sol-gel hydrothermal methods. The seed layer was first grown by sol-gel methods and then annealed at temperatures of 300ºC, 400ºC, 500ºC and 600ºC. Multiple material and optical analyses including field-emission scanning electron microscope, energy dispersive X-ray spectroscopy, X-ray diffraction, photoluminescence spectra, and Raman spectra were conducted to examine the growth orientation and material properties. Results indicate that the ZnO nanorods annealed at a proper temperature of 400ºC could enhance orientation and material quality.

scholarly journals ZnO (Ag-N) Nanorods Films Optimized for Photocatalytic Water Purification

Coatings ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 767 ◽  
Author(s):  
Luis Sanchez ◽  
Carlos Castillo ◽  
Willy Cruz ◽  
Bryan Yauri ◽  
Miguel Sosa ◽  
...  
Keyword(s):  
Nitrogen Content ◽  
Seed Layer ◽  
Zno Nanorods ◽  
Metallic Silver ◽  
Silver Nanostructures ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Mean Diameter ◽  
The Mean

ZnO nanorods (NRs) films, nitrogen-doped (ZnO:N), and ZnO doped with nitrogen and decorated with silver nanostructures (ZnO:N-Ag) NRs films were vertically supported on undoped and N doped ZnO seed layers by a wet chemical method. The obtained films were characterized structurally by X-ray diffraction. Morphological and elemental analysis was performed by scanning electron microscopy, including an energy dispersive X-ray spectroscopy facility and their optical properties by Ultraviolet-Visible Spectroscopy. Analysis performed in the NRs films showed that the nitrogen content in the seed layer strongly affected their structure and morphology. The mean diameter of ZnO NRs ranged from 70 to 190 nm. As the nitrogen content in the seed layer increased, the mean diameter of ZnO:N NRs increased from 132 to 250 nm and the diameter dispersion decreased. This diameter increase occurs simultaneously with the incorporation of nitrogen into the ZnO crystal lattice and the increase in the volume of the unit cell, calculated using the X-ray diffraction patterns and confirmed by a slight shift in the XRD angle. The diffractograms indicated that the NRs have a hexagonal wurtzite structure, with preferential growth direction along the c axis. The SEM images confirmed the presence of metallic silver in the form of nanoparticles dispersed on the NRs films. Finally, the degradation of methyl orange (MO) in an aqueous solution was studied by UV-vis irradiation of NRs films contained in the bulk of aqueous MO solutions. We found a significant enhancement of the photocatalytic degradation efficiency, with ZnO:N-Ag NRs film being more efficient than ZnO:N NRs film, and the latter better than the ZnO NRs film.

Growth of Aligned ZnO Nanorods Grown on Polyethylene Naphthalate Substrates: Effect of the Growth Duration

2014 ◽  
Vol 925 ◽  
pp. 195-199 ◽  
Author(s):  
Reza Shabannia ◽  
Abu Hassan Haslan
Keyword(s):  
Seed Layer ◽  
Room Temperature ◽  
Zno Nanorods ◽  
Average Diameter ◽  
Diffraction Field ◽  
X Ray Diffraction ◽  
Polyethylene Naphthalate ◽  
Growth Duration ◽  
Xrd Pattern ◽  
X Ray

Aligned ZnO nanorods were synthesized on a polyethylene naphthalate (PEN) substrates using a chemical bath deposition method. The growth temperature and precursor concentration were 95 °C and 0.025 M, respectively. The effects of growth duration (2 h to 8 h) on the optical and structural properties of the obtained ZnO nanorods on seed layer ZnO/PEN substrate were then investigated using X-ray diffraction, field-emission scanning electron microscopy (FESEM), and photoluminescence (PL) spectroscopy at room temperature. The high intensity of (002) peak compared with (100) and (101) in the X-ray diffraction (XRD) pattern demonstrated that the ZnO nanorods grown for 6.5 h had more vertical higher crystal quality than the samples grown for other durations. The average diameter of ZnO nanorods grown on PEN substrates increased from 19 nm to 45 nm with increased growth duration from 2 h to 8 h, respectively.

scholarly journals Direct Production of a Novel Iron-Based Nanocomposite from the Laser Pyrolysis ofFe(CO)5/MMAMixtures: Structural and Sensing Properties

2010 ◽  
Vol 2010 ◽  
pp. 1-12 ◽  
Author(s):  
R. Alexandrescu ◽  
I. Morjan ◽  
A. Tomescu ◽  
C. E. Simion ◽  
M. Scarisoreanu ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Gas Sensors ◽  
High Sensitivity ◽  
X Ray Diffraction ◽  
Direct Production ◽  
X Ray ◽  
Metallic Particles ◽  
Ir Laser ◽  
Iron Iron ◽  
Optimum Working

Iron/iron oxide-based nanocomposites were prepared by IR laser sensitized pyrolysis ofFe(CO)5and methyl methacrylate (MMA) mixtures. The morphology of nanopowder analyzed by TEM indicated that mainly core-shell structures were obtained. X-ray diffraction techniques evidence the cores as formed mainly by iron/iron oxide crystalline phases. A partially degraded (carbonized) polymeric matrix is suggested for the coverage of the metallic particles. The nanocomposite structure at the variation of the laser density and of the MMA flow was studied. The new materials prepared as thick films were tested for their potential for acting as gas sensors. The temporal variation of the electrical resistance in presence ofNO2, CO, andCO2, in dry and humid air was recorded. Preliminary results show that the samples obtained at higher laser power density exhibit rather high sensitivity towardsNO2detection andNO2selectivity relatively to CO andCO2. An optimum working temperature of200°Cwas found.

EFFECT OF PRE-HEATING AND SEED LAYER ON HYDROTHERMAL GROWTH AND OPTICAL PROPERTIES OF ZINC OXIDE NANORODS

2011 ◽  
Vol 10 (04n05) ◽  
pp. 845-849
Author(s):  
GAURAV SHUKLA ◽  
ALIKA KHARE
Keyword(s):  
Optical Properties ◽  
Seed Layer ◽  
Zno Nanorods ◽  
Pulsed Laser ◽  
Heating Time ◽  
Hydrothermal Growth ◽  
Zinc Oxide Nanorods ◽  
Growth Time ◽  
Oxide Nanorods ◽  
Reported Effect

Hydrothermal growth of highly c-axis oriented ZnO nanorods with high aspect ratio on pulsed laser deposited ZnO seed layer is reported. Effect of pre-heating time, growth time and seed layer on the structural, morphological and optical properties of ZnO nanorods is presented. The possible growth mechanism for ZnO nanorods is also discussed.

scholarly journals Studies on the Growth Control of ZnO Nanostructures synthesized by the Chemical Method

2018 ◽  
Vol 23 (2) ◽  
Author(s):  
Patricia María Perillo ◽  
Mariel Nahir Atia ◽  
Daniel Fabián Rodríguez
Keyword(s):  
Chemical Method ◽  
Morphological Evolution ◽  
Zno Nanorods ◽  
Growth Control ◽  
Zno Nanostructures ◽  
X Ray Diffraction ◽  
Wurtzite Phase ◽  
X Ray ◽  
Hexagonal Wurtzite Phase

ABSTRACT ZnO nanostructures were synthesized through a chemical method using different Zn precursors and hexamethylenetetramine (HMTA) at 90 °C. The effects of the reactants on the morphological evolution of ZnO nanorods were investigated. The samples were characterized by using XRD, SEM, EDX and BET. The hexagonal wurtzite phase of ZnO was confirmed by X-ray diffraction (XRD). The performed analysis indicated that different morphologies were obtained by changing the reactants.

scholarly journals Construction of Two Stable Co(II)-Based Hydrogen-Bonded Organic Frameworks as a Luminescent Probe for Recognition of Fe3+ and Cr2O72− in H2O

Molecules ◽  
2021 ◽  
Vol 26 (19) ◽  
pp. 5955
Author(s):  
Qi-Ying Weng ◽  
Ya-Li Zhao ◽  
Jia-Ming Li ◽  
Miao Ouyang
Keyword(s):  
Detection Limit ◽  
Aqueous Media ◽  
Three Dimensional ◽  
Cobalt Atom ◽  
High Sensitivity ◽  
X Ray Diffraction ◽  
Chlorobenzoic Acid ◽  
X Ray ◽  
Highly Sensitive ◽  
Hydrogen Bonded

A pair of cobalt(II)-based hydrogen-bonded organic frameworks (HOFs), [Co(pca)2(bmimb)]n (1) and [Co2(pca)4(bimb)2] (2), where Hpca = p-chlorobenzoic acid, bmimb = 1,3-bis((2-methylimidazol-1-yl)methyl)benzene, and bimb = 1,4-bis(imidazol-1-ylmethyl)benzene were hydrothermally synthesized and characterized through infrared spectroscopy (IR), elemental and thermal analysis (EA), power X-ray diffraction (PXRD), and single-crystal X-ray diffraction (SCXRD) analyses. X-ray diffraction structural analysis revealed that 1 has a one-dimensional (1D) infinite chain network through the deprotonated pca− monodentate chelation and with a μ2-bmimb bridge Co(II) atom, and 2 is a binuclear Co(II) complex construction with a pair of symmetry-related pca− and bimb ligands. For both 1 and 2, each cobalt atom has four coordinated twisted tetrahedral configurations with a N2O2 donor set. Then, 1 and 2 are further extended into three-dimensional (3D) or two-dimensional (2D) hydrogen-bonded organic frameworks through C–H···Cl interactions. Topologically, HOFs 1 and 2 can be simplified as a 4-connected qtz topology with a Schläfli symbol {64·82} and a 4-connected sql topology with a Schläfli symbol {44·62}, respectively. The fluorescent sensing application of 1 was investigated; 1 exhibits high sensitivity recognition for Fe3+ (Ksv: 10970 M−1 and detection limit: 19 μM) and Cr2O72− (Ksv: 12960 M−1 and detection limit: 20 μM). This work provides a feasible detection platform of HOFs for highly sensitive discrimination of Fe3+ and Cr2O72− in aqueous media.

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