Effect of Zn Nitrate Hexahydrate Concentration on ZnO Nanorods Grown from an Electrochemically Oxidized ZnO Seed Layer

ABSTRACTControlled ZnO nanostructures were grown on a flexible substrate for the future development of smart sensing tags. Thermolysis-assisted chemical solution deposition was used to grow ZnO nanorods at 85°C from 0.01mol of Zinc nitrate hexahydrate and HMT (Hexamethyltetramine) solution. To promote and modulate the ZnO nanorods, R.F. sputtered ZnO seed layers were deposited on polyimide substrates at various film thicknesses in the range of 8 to 160 nm. The optimum processing conditions to fabricate ZnO nanostructures have been investigated to examine the growth behaviors and to correlate the process parameters with the morphological characteristics. When the ethanol gas sensitivities were measured at different thickness of ZnO seed layers before growing ZnO nanorods, the highest sensitivity was obtained at 40 nm thick ZnO film at 300°C where the film thickness is similar to the Debye length. When ZnO nanorods were grown on such a ZnO seed layer, the sensitivities were more heavily influenced by the ZnO nanostructures rather than the thickness of the seed layer probably due to the dominant proportion of carrier density involved with the gas absorption.

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Effect of ZnO Seed Layer with Various Concentrations of Precursor on the Growth of ZnO Nanostructures

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.675-676.237 ◽

2016 ◽

Vol 675-676 ◽

pp. 237-240

Author(s):

Nontakoch Siriphongsapak ◽

Somyod Denchicharoen ◽

Pichet Limsuwan

Keyword(s):

Zinc Acetate ◽

Seed Layer ◽

Zinc Acetate Dihydrate ◽

Zno Nanorods ◽

Crystallographic Structure ◽

Nitrate Hexahydrate ◽

X Rays ◽

Zno Nanostructures ◽

Acetate Dihydrate ◽

Seed Layers

In this work, Zinc oxide (ZnO) thin films were deposited on silicon and glass substrates using spin-coating method with different concentrations of precursor (zinc acetate dihydrate) and stabilizer (monoethanolamine). The concentrations of zinc acetate dihydrate and monoethanolamine in isopropanol were varied from 6 mM to 500 mM. Subsequently, the substrate with ZnO thin film as a seed layer was used to grow ZnO nanostructures by hydrothermal process with the same concentration of precursor (zinc nitrate hexahydrate), temperature, and time for each growth. The samples were characterized by field-emission scanning electron microscopy (FESEM), X-rays diffractometer (XRD), and UV-visible spectrophotometer (UV-vis) to study morphology, crystallographic structure, and optical property, respectively. The results showed that particle size, crystallinity, and transmittance of seed layers were changed with increasing concentrations of spin-coated precursor. Furthermore, the nanostructures were found that higher precursor concentration of seed layers affected the formation of ZnO nanorods to be nanosheets.

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ZnO NANORODS GROWN ON PLASTIC PVC SUBSTRATE FOR ENVIRONMENTAL APPLICATION

Journal of Military Science and Technology ◽

10.54939/1859-1043.j.mst.67.2020.149-153 ◽

2020 ◽

pp. 149-153

Author(s):

Hanh

Keyword(s):

Methylene Blue ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Seed Layer ◽

Zno Nanorods ◽

Zinc Nitrate ◽

Zinc Nitrate Hexahydrate ◽

Nitrate Hexahydrate ◽

Environmental Application ◽

Scanning Electron

In this work, the hydrothermal growth of ZnO nanorods (NRs) on plastic PVC substrate is presented. It was shown that ZnO NRs with high density and high crystallinity can be successfully grown by implementing saturated nutrition solution of zinc nitrate hexahydrate (Zn[NO3]2·6H2O) and hexamethylenetetramine (C6H12N4) without the assistance of a seed layer. The morphologies of the ZnO nanorods investigated by scanning electron microscope (SEM) demonstrated hexagonal structures. The crystallinity of the ZnO NRs was studied by photoluminescence (PL) spectroscopy. The as-grown ZnO NRs were then utilized for photocatalytic degradation of methylene blue.

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

International Journal of Nanoscience ◽

10.1142/s0219581x11009283 ◽

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.

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EFFECT OF HYDROTHERMAL TIME ON THE GROWTH OF ZnO NANORODS

Journal of Military Science and Technology ◽

10.54939/1859-1043.j.mst.66a.2020.84-91 ◽

2020 ◽

pp. 84-91

Author(s):

Hanh

Keyword(s):

Printed Circuit Board ◽

Low Cost ◽

Cell Structure ◽

Zno Nanorods ◽

Zinc Nitrate ◽

Circuit Board ◽

Nitrate Hexahydrate ◽

Hydrothermal Time ◽

One Step ◽

Surface Morphologies

In this work, ZnO nanorods (NRs) were successfully grown on printed circuit board substrates (PCBs) by utilizing a one-step, seedless, low-cost hydrothermal method. It was shown that by implementing a galvanic cell structure in an aqueous solution of 80 mM of zinc nitrate hexahydrate and hexamethylenetetramine, ZnO NRs can directly grow on the PCBs substrate without the assistance of a seed layer. The effect of hydrothermal time on the surface morphologies, and the crystallinity of the as-grown ZnO nanorods (NRs) was also investigated. The as-grown ZnO NRs also exhibited a significant enhancement in vertical growth and their crystallinity with 5 hour growth.

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Hierarchical growth of ZnO nanorods over SnO2 seed layer: insights into electronic properties from photocatalytic activity

RSC Advances ◽

10.1039/c5ra23824b ◽

2016 ◽

Vol 6 (3) ◽

pp. 2112-2118 ◽

Cited By ~ 29

Author(s):

Luís F. Da Silva ◽

Osmando F. Lopes ◽

Ariadne C. Catto ◽

Waldir Avansi ◽

Maria I. B. Bernardi ◽

...

Keyword(s):

Photocatalytic Activity ◽

Electronic Properties ◽

Hydrothermal Treatment ◽

Charge Separation ◽

Seed Layer ◽

Photocatalytic Performance ◽

Zno Nanorods

The ZnO–SnO2 heterojunction catalyst was prepared via a hydrothermal treatment route. The heterojunction exhibited a superior photocatalytic performance in comparison to SnO2 and ZnO, attributed to the good charge separation.

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Synthesis and Characterization of ZnO Nanorods as an Adsorbent for Cr(VI) Sequestration

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2018-1203 ◽

2019 ◽

Vol 233 (7) ◽

pp. 995-1017 ◽

Cited By ~ 9

Author(s):

Sadia Ata ◽

Anila Tabassum ◽

Ismat Bibi ◽

Samina Ghafoor ◽

Abdul Ahad ◽

...

Keyword(s):

Zno Nanorods ◽

Zinc Nitrate ◽

Nitrate Hexahydrate ◽

Order Kinetic ◽

Hydrothermal Route ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Isotherms And Thermodynamics ◽

Heavy Metals Ions ◽

Triton X

Abstract Zinc oxide (ZnO) nanorods were fabricated through hydrothermal route and employed for the adsorption of Cr(VI) ions from aqueous medium. Zinc nitrate hexahydrate (Zn(NO3)2.6H2O) was used as a zinc precursor and Triton-x 100 was used as a capping agent. As synthesized ZnO nanorods were characterized by UV-visible spectroscopy (UV), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy dispersive X-Ray spectroscopy (EDX) techniques. The adsorption affecting parameters were investigated for maximum adsorption of Cr(VI) onto ZnO nanorods. The adsorption kinetics, isotherms, and thermodynamics were applied for adsorption mechanism evaluation. Maximum adsorption of Cr(VI) ions (250 mg/g) was achieved using 0.055 g/L ZnO dose at pH 2.0 for the contact time of 30 min. Pseudo-second-order kinetic model and Langmuir isotherm explained well the Cr(VI) adsorption onto ZnO nanorods. The Cr(VI) adsorption onto ZnO was spontaneous and endothermic in nature. In view of promising adsorption efficiency, ZnO nanorods could possibly be used for Cr(VI) ions removal from wastewater and also extendable for the adsorption of other heavy metals ions.

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

Surface Review and Letters ◽

10.1142/s0218625x19501981 ◽

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).

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