scholarly journals Site-specific growth of oriented ZnO nanocrystal arrays

2019 ◽  
Vol 10 ◽  
pp. 274-280 ◽  
Author(s):  
Rekha Bai ◽  
Dinesh K Pandya ◽  
Sujeet Chaudhary ◽  
Veer Dhaka ◽  
Vladislav Khayrudinov ◽  
...  
Keyword(s):  
Pore Size ◽  
Indium Tin Oxide ◽  
Cost Effective ◽  
X Ray Diffraction ◽  
Site Specific ◽  
Zno Nanocrystals ◽  
Hexagonal Shape ◽  
Facile Fabrication ◽  
Vertically Aligned ◽  
Zno Nanocrystal

We report on the growth of ZnO nanocrystals having a hexagonal, prismatic shape, sized 700 nm × 600 nm, on bare indium tin oxide (ITO) substrates. The growth is induced by a low ion flux and involves a low-temperature electrodeposition technique. Further, vertically aligned periodic nanocrystal (NC) growth is engineered at predefined positions on polymer-coated ITO substrates patterned with ordered pores. The vertical alignment of ZnO NCs along the c-axis is achieved via ion-by-ion nucleation-controlled growth for patterned pores of size ≈600 nm; however, many-coupled branched NCs with hexagonal shape are formed when a patterned pore size of ≈200 nm is used. X-ray diffraction data is in agreement with the observed morphology. A mechanism is proposed to interpret the observed site-specific oriented/branched growth that is correlated to the pore size. As ordered NC arrays have the potential to generate new collective properties different from single NCs, our first demonstration of a cost effective and facile fabrication process opens up new possibilities for devices with versatile functionalities.

Rectifying Behavior of Aligned ZnO Nanorods on Mg0.3Zn0.7O Thin Film Template

2011 ◽  
Vol 364 ◽  
pp. 35-39 ◽  
Author(s):  
Salina Muhamad ◽  
Abu Bakar Suriani ◽  
Mohamad Hafiz Mamat ◽  
Rafidah Ahmad ◽  
Mohamad Rusop
Keyword(s):  
Thin Film ◽  
Zno Nanorods ◽  
Thermionic Emission ◽  
Deposition Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hexagonal Shape ◽  
Semiconductor Junction ◽  
Vertically Aligned ◽  
Scanning Electron

Rectifying behavior more than 3 orders of aligned zinc oxide (ZnO) nanorods grown on Mg0.3Zn0.7O thin film template using chemical bath deposition method was observed, giving a barrier height of 0.75 eV, and the ideality factor achieved was almost 6, which was analyzed using thermionic emission theory. Field emission scanning electron microscope (FESEM) images revealed that the grown ZnO was in hexagonal shape, uniformly distributed and in vertically aligned form. The crystallinity of the sample being studied using X-ray diffraction (XRD), where the highest peak was found at (002) phase, confirming that high crytallinity of ZnO was attained. The effect of metal/semiconductor junction between metal and aligned ZnO nanorods was discussed in further details.

Study of Heating Effect on Specific Surface Area, and Changing Optical Properties of ZnO Nanocrystals

2011 ◽  
Vol 403-408 ◽  
pp. 1205-1210
Author(s):  
Jaleh Babak ◽  
Ashrafi Ghazaleh ◽  
Gholami Nasim ◽  
Azizian Saeid ◽  
Golbedaghi Reza ◽  
...  
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Energy Gap ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zno Nanocrystals ◽  
Transmission Electron ◽  
Zno Nanocrystal

In this work ZnO nanocrystal powders have been synthesized by using Zinc acetate dehydrate as a precursor and sol-gel method. Then the products have been annealed at temperature of 200-1050°C, for 2 hours. The powders were characterized using X-ray diffraction (XRD), UV-vis absorption and photoluminescence (PL) spectroscopy. The morphology of refrence ZnO nanoparticles have been studied using Transmission Electron Microscope (TEM). During the annealing process, increase in nanocrystal size, defects and energy gap quantitative, and decrease in specific surface area have been observed.

Polyaniline nanowire arrays generated through oriented mesoporous silica films: effect of pore size and spectroelectrochemical response

2021 ◽  
Author(s):  
Wahid Ullah ◽  
Gregoire Herzog ◽  
neus vila ◽  
Alain Walcarius
Keyword(s):  
Mesoporous Silica ◽  
Pore Size ◽  
Tin Oxide ◽  
Indium Tin Oxide ◽  
Self Assembly ◽  
Cationic Surfactants ◽  
Nanowire Arrays ◽  
Silica Films ◽  
Oxide Electrodes ◽  
Vertically Aligned

Indium-tin oxide electrodes modified with vertically aligned silica nanochannel membrane have been produced by electrochemically assisted self-assembly of cationic surfactants (cetyl- or octadecyl-trimethylammonium bromide) and concomitant polycondensation of the silica...

Growth of Ruthenium and Ruthenium oxide nanoplates

2011 ◽  
Vol 1309 ◽  
Author(s):  
Lamartine Meda ◽  
Geoffrey D. Stevens
Keyword(s):  
Indium Tin Oxide ◽  
Ruthenium Oxide ◽  
Chemical Vapor ◽  
Growth Conditions ◽  
X Ray Diffraction ◽  
Coated Glass Substrate ◽  
X Ray ◽  
Average Area ◽  
Continuous Layer ◽  
Vertically Aligned

ABSTRACTBy carefully manipulating and controlling the growth conditions, Ruthenium (Ru) and ruthenium oxide (RuO2) two-dimensional (2-D) nanostructure were self-assembled into a stack of plates on indium tin oxide coated glass substrate. The nanoplates were grown in a horizontal hot-wall metalorganic chemical vapor deposition (MOCVD) from ruthenocene. Each nanoplate has a thickness in the range of 25 - 60 nm and the average area is 1000 x 300 nm2. Each stack of nanoplates is approximately 1.2 m in height. A continuous layer of Ru and RuO2 thin film, which may serve as the growth template, is observed on the bottom of the nanoplate stacks. Field-emission scanning electron microscopy reveals that each stack of nanoplates was grown vertically aligned on the substrate and exhibited elongated shape. Structural properties which were examined by X-ray diffraction show that the nanoplates are polycrystalline.

Low-Temperature Synthesis of Nanocrystalline ZnO Nanorods Arrays

2013 ◽  
Vol 770 ◽  
pp. 237-240
Author(s):  
S. Kalasung ◽  
C. Chananonnawathorn ◽  
Mati Horprathum ◽  
P. Thongpanit ◽  
Pitak Eiamchai ◽  
...  
Keyword(s):  
Low Temperature ◽  
Zno Nanorods ◽  
Cost Effective ◽  
Zinc Nitrate ◽  
Nitrate Hexahydrate ◽  
X Ray Diffraction ◽  
Thickness Change ◽  
Growth Method ◽  
Vertically Aligned ◽  
Seed Layer Thickness

In this present research, vertically aligned ZnO nanorods arrays were grown on silicon wafer (100) substrates from a zinc nitrate hexahydrate and hexamethylenetetramine solution by a cost effective and low temperature (90 °C) hydrothermal growth method. Field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) were used to analyze morphology, crystallinity and film thickness, respectively. It was demonstrated that when the seed layer thickness change from 18 to 200 nm, the nanowire density increased. Our result presented a scalable method for fabricating ZnO nanorods arrays with potential for a lots of application such as micro/nanosensors and the nanoelectronic devices.

scholarly journals Photocatalytic Degradation of Methylene Blue and Metanil Yellow Dyes Using Green Synthesized Zinc Oxide (ZnO) Nanocrystals

Crystals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 22
Author(s):  
S. Shwetha Priyadharshini ◽  
Jayachamarajapura Pranesh Shubha ◽  
Jaydev Shivalingappa ◽  
Syed Farooq Adil ◽  
Mufsir Kuniyil ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Cost Effective ◽  
Sem Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zno Nanocrystals ◽  
Cost Effective Method ◽  
Photocatalytic Activities ◽  
Ft Ir ◽  
Metanil Yellow

In this work, ZnO nanocrystals (NCs) have been effectively synthesized by a simple, efficient and cost-effective method using coconut husk extract as a novel fuel. The synthesized NCs are characterized by UV-Vis, XRD, FT-IR, SEM, EDX, Raman and PL studies. The obtained ZnO were found to be UV-active with a bandgap of 2.93 eV. The X-ray diffraction pattern confirms the crystallinity of the ZnO with hexagonally structured ZnO with a crystallite size of 48 nm, while the SEM analysis reveals the hexagonal bipyramid morphology. Photocatalytic activities of the synthesized ZnO NCs are used to degrade methylene blue and metanil yellow dyes.

scholarly journals Growth of the Electrodeposited NiX2 (X= Te, Se) Thin Films

2020 ◽  
pp. 55-69
Author(s):  
T. Joseph Sahaya Anand ◽  
Rajes K. M. Rajan ◽  
Md Radzai Said ◽  
Lau Kok Tee
Keyword(s):  
Thin Films ◽  
Indium Tin Oxide ◽  
Compositional Analysis ◽  
Cost Effective ◽  
Xrd Analysis ◽  
Potential Range ◽  
X Ray Diffraction ◽  
X Ray ◽  
Glass Substrates ◽  
P Type

Thin films of nickel chalcogenide, NiX2 (X= Te, Se) have been electrosynthesized on indium-tin-oxide (ITO) coated glass substrates. The films were characterized for their structural, morphological and compositional characteristics. Consisting of transition metals and chalcogenides (S, Se and Te), they show promising solar absorbent properties such as semiconducting band gap, well adhesion to substrate and good conversion with better cost-effective. Cyclic voltammetry experiments have been done prior to electrodeposition in order to get the electrodeposition potential range where the observable reduction range is between -0.9-(-1.1) V. Their optical and semiconducting parameters were also analysed in order to determine the suitability of the thin films for photoelectrochemical (PEC) / solar cell applications. Structural analysis via X-ray diffraction (XRD) analysis reveals that the films are polycrystalline in nature. Scanning electron microscope (SEM) studies reveals that the films were adherent to the substrate with uniform and pin-hole free. Compositional analysis via energy dispersive X-ray (EDX) technique confirms the presence of Ni, Te, and Se elements in the films. The optical studies show that the films are of direct bandgap. Results on the semiconductor parameters analysis of the films showed that the nature of the Mott-Schottky plots indicates that the films obtained are of p-type material.

Ion Beam Synthesis and Optical Properties of Zn and Zno Nanocrystals in Sio2 and Caf2 Substrates

2003 ◽  
Vol 777 ◽  
Author(s):  
Y.C. Liu ◽  
R. Mu ◽  
H.Y. Xu ◽  
Y.M. Lu ◽  
D.Z. Shen ◽  
...  
Keyword(s):  
Ion Beam ◽  
Green Emission ◽  
Zinc Ions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Reducing Atmosphere ◽  
Zno Nanocrystals ◽  
Nanocrystal Formation ◽  
Beam Damage ◽  
Zno Nanocrystal

AbstractIon implantation was used to inject zinc ions into crystalline CaF2 and amorphous SiO2 substrates. Zn or ZnO nanoparticles were formed after annealing in a reducing (4% H2 + 96%Ar) or an oxidizing (10%O2 + 90% Ar ) atmosphere, respectively. When the sample was annealed in a reducing atmosphere, the absorption band at ∼ 5.3 eV for zinc implanted into SiO2 was attributed to zinc metal colloids. The absorption peak observed in the 4.3 – 4.7 eV region was due to the formation of ZnO nanocrystals, after the sample was annealed in an oxidizing environment. Both X-ray diffraction (XRD) and X-ray photospectroscopy (XPS) were used to confirm ZnO nanocrystal formation. For zinc implanted into CaF2, the as-formed ZnO nanocrystals were aligned with their [002] axes parallel to the [111] axis of the CaF2. Photoluminescence (PL) spectra showed UV and green emission from the zinc-implanted silica samples annealed under an oxygen atmosphere; however, no green emission was observed for ZnO formed in a CaF2 substrate. An additional emission was observed at ∼ 420 nm which might be due to F centers in CaF2 created by ion beam damage.

Structure and Properties of Doped ZnO Nanopowders Synthesized by Methanol Alcoholysis Method

2011 ◽  
Vol 287-290 ◽  
pp. 1406-1411
Author(s):  
Yi Chuan Chen ◽  
Yue Hui Hu ◽  
Xiao Hua Zhang ◽  
Feng Yang ◽  
Hai Jun Xu ◽  
...  
Keyword(s):  
Luminescent Properties ◽  
X Ray Diffraction ◽  
Blue Band ◽  
Band Emission ◽  
Zno Nanocrystals ◽  
Green Band Emission ◽  
Transmission Electron ◽  
Structure Morphology ◽  
Doped Zno ◽  
Zno Nanocrystal

Pured ZnO, Al doped ZnO and Al-In co-doped ZnO nanopowders were synthesized by the methanol alcoholysis method at 130 °C. Structure, morphology and optical properties of ZnO nanopowders were characterized using X-ray diffraction, Transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and Photoluminescence (PL) spectra. The results show that ZnO nanopowders can be obtained in methanol solution at low temperature (130 °C). TEM images show that Al doped ZnO nanocrystals grow along the [002] axis quicker than other axes. FTIR spectra show that ZnO nanocrystals synthesized by the methanol alcoholysis include a little organic impurity. PL spectrums reveal that pure ZnO and doped ZnO nanocrystals have a blue band emission at 440 nm and a green band emission at 520 nm and 530 nm, respectively. Compared with the pure ZnO nanocrystal, the Al doping improves the luminescent properties.

Polygonal profiles of ferritin molecules

1983 ◽  
Vol 41 ◽  
pp. 600-601
Author(s):  
William H. Massover
Keyword(s):  
Axial Ratio ◽  
X Ray Diffraction ◽  
Rhombic Dodecahedron ◽  
Apparent Contradiction ◽  
Iron Storage ◽  
X Ray ◽  
Hexagonal Shape ◽  
Axes Of Symmetry ◽  
Apparent Conflict ◽  
Iron Storage Protein

The molecular structure of the iron-storage protein, ferritin, is becoming known in ever finer detail. The 24 apoferritin subunits (MW ca. 20,000) have a 2:1 axial ratio and are polymerized with 4:3:2 symmetry to form an outer shell surrounding a variable amount of microcrystalline iron, Recent x-ray diffraction results indicate that the projected outline of the native molecule has a quasi-hexagonal shape when viewed down the 3-fold axes of symmetry, and a quasi-square shape when looking down the 4-fold axes. To date, no electron microscope study has reported observing anything other than circular profiles, which would indicate that ferritin is strictly spherical. The apparent conflict between the "hollow sphere" of electron microscopy (E.M.) and the "truncated rhombic dodecahedron" of x-ray diffraction could reflect the poorer effective resolution of E.M. coming from radiation damage, staining, drying, etc. The present study investigates the detailed shape of individual ferritin molecules in order to search for the predicted aspherical profiles and to interpret the nature of this apparent contradiction.

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