scholarly journals Optical Properties of Indium Doeped ZnO Nanowires

2015 ◽  
Vol 2015 ◽  
pp. 1-6
Author(s):  
Tsung-Shine Ko ◽  
Sin-Liang Ou ◽  
Kuo-Sheng Kao ◽  
Tz-Min Yang ◽  
Der-Yuh Lin
Keyword(s):  
Electron Microscopy ◽  
Blue Shift ◽  
Zno Nanowires ◽  
Near Band Edge ◽  
X Ray Diffraction ◽  
Thermal Evaporation Method ◽  
Transmission Electron ◽  
Energy Dispersion Spectrum ◽  
Vapor Liquid Solid Mechanism

We report the synthesis of the ZnO nanowires (NWs) with different indium concentrations by using the thermal evaporation method. The gold nanoparticles were used as the catalyst and were dispersed on the silicon wafer to facilitate the growth of the ZnO NWs. High resolution transmission electron microscopy confirms that the ZnO NWs growth relied on vapor-liquid-solid mechanism and energy dispersion spectrum detects the atomic percentages of indium in ZnO NWs. Scanning electron microscopy shows that the diameters of pure ZnO NWs range from 20 to 30 nm and the diameters of ZnO:In were increased to 50–80 nm with increasing indium doping level. X-ray diffraction results point out that the crystal quality of the ZnO NWs was worse with doping higher indium concentration. Photoluminescence (PL) study of the ZnO NWs exhibited main photoemission at 380 nm due to the recombination of excitons in near-band-edge (NBE). In addition, PL results also indicate the slightly blue shift and PL intensity decreasing of NBE emission from the ZnO NWs with higher indium concentrations could be attributed to more donor-induced trap center generations.

SYNTHESIS, STRUCTURE, AND LUMINESCENCE PROPERTIES OF ZnSnO3 NANOWIRES

NANO ◽  
2012 ◽  
Vol 07 (02) ◽  
pp. 1250013 ◽  
Author(s):  
SOYEON AN ◽  
CHANGHYUN JIN ◽  
HYUNSU KIM ◽  
SANGMIN LEE ◽  
BONGYONG JEONG ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Green Emission ◽  
Blue Shift ◽  
Zno Nanowires ◽  
X Ray Diffraction ◽  
Ultraviolet Emission ◽  
Violet Emission ◽  
X Ray ◽  
Transmission Electron

ZnSnO3 nanowires were synthesized on Si substrates by thermal evaporation of a mixture of ZnO, SnO2 and graphite powders. The nanowires were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and photoluminescence spectroscopy. The ZnSnO3 nanowires varied from 10 to 100 nm in diameter and up to a few hundred of micrometers in length. Transmission electron microscopy and X-ray diffraction revealed that the nanowires are multiphase nanostructures containing ZnSnO3, Zn2SnO4, ZnO, and SnO2 phases. Photoluminescence measurements showed that ZnSnO3 nanowires had a sharp ultraviolet emission peak at approximately 375 nm as well as a broad green emission band centered at approximately 510 nm. The violet emission of ZnSnO3 nanowires exhibits a blue shift by approximately 5 nm compared to that of ZnO nanowires and the visible emission of ZnO nanowires shifted from the orange region to the green region, which should be attributed to the narrowing of Eg. Thermal annealing enhanced the green emission but degraded the ultraviolet emission of the ZnSnO3 nanowires. In addition, the origin of the enhanced luminescence of ZnSnO3 nanowires compared to ZnO and SnO2 nanowires is discussed.

scholarly journals Controlled Synthesis of CuS and Cu9S5 and Their Application in the Photocatalytic Mineralization of Tetracycline

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 899
Author(s):  
Murendeni P. Ravele ◽  
Opeyemi A. Oyewo ◽  
Damian C. Onwudiwe
Keyword(s):  
Electron Microscopy ◽  
Visible Light ◽  
Blue Shift ◽  
X Ray Diffraction ◽  
X Ray ◽  
Copper Sulfides ◽  
Transmission Electron ◽  
Single Source Precursor ◽  
Pure Phase ◽  
Pure Phases

Pure-phase Cu2−xS (x = 1, 0.2) nanoparticles have been synthesized by the thermal decomposition of copper(II) dithiocarbamate as a single-source precursor in oleylamine as a capping agent. The compositions of the Cu2−xS nanocrystals varied from CuS (covellite) through the mixture of phases (CuS and Cu7.2S4) to Cu9S5 (digenite) by simply varying the temperature of synthesis. The crystallinity and morphology of the copper sulfides were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), which showed pure phases at low (120 °C) and high (220 °C) temperatures and a mixture of phases at intermediate temperatures (150 and 180 °C). Covellite was of a spherical morphology, while digenite was rod shaped. The optical properties of these nanocrystals were characterized by UV−vis–NIR and photoluminescence spectroscopies. Both samples had very similar absorption spectra but distinguishable fluorescence properties and exhibited a blue shift in their band gap energies compared to bulk Cu2−xS. The pure phases were used as catalysts for the photocatalytic degradation of tetracycline (TC) under visible-light irradiation. The results demonstrated that the photocatalytic activity of the digenite phase exhibited higher catalytic degradation of 98.5% compared to the covellite phase, which showed 88% degradation within the 120 min reaction time using 80 mg of the catalysts. The higher degradation efficiency achieved with the digenite phase was attributed to its higher absorption of the visible light compared to covellite.

Ge Growth on Nanostructured Silicon Surfaces

2005 ◽  
Vol 862 ◽  
Author(s):  
Ganesh Vanamu ◽  
Abhaya K. Datye ◽  
Saleem H. Zaidi
Keyword(s):  
Electron Microscopy ◽  
Dislocation Density ◽  
Full Width Half Maximum ◽  
Defect Density ◽  
Chemical Vapor ◽  
Silicon Surfaces ◽  
X Ray Diffraction ◽  
Etch Pit ◽  
Transmission Electron

AbstractWe report highest quality Ge epilayers on nanoscale patterned Si structures. 100% Ge films of 10 μm are deposited using chemical vapor deposition. The quality of Ge layers was examined using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high-resolution x-ray diffraction (HRXRD) measurements. The defect density was evaluated using etch pit density measurements. We have obtained lowest dislocation density (5×105 cm-2) Ge films on the nanopatterned Si structures. The full width half maximum peaks of the reciprocal space maps of Ge epilayers on the nanopatterned Si showed 93 arc sec. We were able to get rid of the crosshatch pattern on the Ge surface grown on the nanopatterned Si. We also showed that there is a significant improvement of the quality of the Ge epilayers in the nanopatterned Si compared to an unpatterned Si. We observed nearly three-order magnitude decrease in the dislocation density in the patterned compared to the unpatterned structures. The Ge epilayer in the patterned Si has a dislocation density of 5×105 cm-2 as compared to 6×108 cm-2 for unpatterned Si.

SYNTHESIS OF In2O3 NANOWIRES ENHANCED BY ANODIC ALUMINA MEMBRANE

2006 ◽  
Vol 05 (04n05) ◽  
pp. 479-485
Author(s):  
C. W. LAI ◽  
X. Y. ZHANG ◽  
H. C. ONG ◽  
J. Y. DAI ◽  
H. L. W. CHAN
Keyword(s):  
Electron Microscopy ◽  
Large Scale ◽  
Anodic Alumina ◽  
X Ray Diffraction ◽  
Alumina Membrane ◽  
Thermal Evaporation Method ◽  
Single Crystalline ◽  
X Ray ◽  
Alumina Membranes ◽  
Transmission Electron

Large-scale single crystalline In 2 O 3 nanowires were successfully synthesized on anodic alumina membranes by a simple thermal evaporation method at 570°C. X-ray diffraction, transmission electron microscopy, and scanning electron microscopy studies revealed the formation of single crystalline In 2 O 3 nanowires with diameters of 50–100 nm and lengths of up to a few hundreds of micrometers. Cathodeluminescence study revealed existence of oxygen vacancies evidenced by a strong and broad emission at 470 nm with a shoulder at 400 nm. The growth mechanism of the nanostructures is also discussed.

scholarly journals Synthesis of ZnO Nanowires via Hotwire Thermal Evaporation of Brass (CuZn) Assisted by Vapor Phase Transport of Methanol

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Tamil Many K. Thandavan ◽  
Siti Meriam Abdul Gani ◽  
Chiow San Wong ◽  
Roslan Md Nor
Keyword(s):  
Electron Microscopy ◽  
Vapor Phase ◽  
Thermal Evaporation ◽  
Zno Nanowires ◽  
X Ray Diffraction ◽  
Tem Analysis ◽  
Vapor Phase Transport ◽  
Transmission Electron ◽  
Lattice Planes ◽  
Phase Transport

Zinc oxide (ZnO) nanowires (NWs) were synthesized using vapor phase transport (VPT) and thermal evaporation of Zn from CuZn. Time dependence of ZnO NWs growth was investigated for 5, 10, 15, 20, 25, and 30 minutes. Significant changes were observed from the field electron scanning electron microscopy (FESEM) images as well as from the X-ray diffraction (XRD) profile. The photoluminescence (PL) profile was attributed to the contribution of oxygen vacancy, zinc interstitials, and hydrogen defects in the ZnO NWs. Raman scattering results show a significant peak at 143 cm−1and possible functionalization on the wall of ZnO NWs. Growth of ZnO NWs in (0002) with an estimated distance between adjacent lattice planes 0.26 nm was determined from transmission electron microscopy (TEM) analysis.

Assembly-line flash synthesis of ZnO nanobelts on metal Zn

2017 ◽  
Vol 31 (27) ◽  
pp. 1750250 ◽  
Author(s):  
Qiang Zou ◽  
Shentong Mo ◽  
Yanan Wang ◽  
Mengjiao Dang ◽  
Guoxuan Qin ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Assembly Line ◽  
Production Method ◽  
X Ray Diffraction ◽  
Average Width ◽  
Line Production ◽  
Whole Process ◽  
Transmission Electron ◽  
Auxiliary Process

In this study, ZnO nanobelts were successfully fabricated by flash synthesis without any expensive catalyst at a relatively low temperature (600[Formula: see text]C). The whole process took just [Formula: see text][Formula: see text]30 min. Introducing a solution tank containing a mixture of polyvinyl alcohol (PVA) and Zn(AC)2, was an auxiliary process to elevate the quality of the products. The morphology of the ZnO nanobelts was systematically investigated by means of field emission scanning electron microscopy (FRSEM) and high-resolution transmission electron microscopy (HRTEM). The products had an average width of 200[Formula: see text]nm and a length of more than 10[Formula: see text][Formula: see text]. X-ray diffraction analysis indicated that the ZnO nanobelts had a typical wurtzite structure. Finally, the growth mechanism of the unique morphology of the ZnO nanobelts is discussed. An assembly-line production method is also proposed based on the results.

scholarly journals Structural Characterization of Al0.37In0.63N/AlN/p-Si (111) Heterojunctions Grown by RF Sputtering for Solar Cell Applications

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2236
Author(s):  
Arántzazu Núñez-Cascajero ◽  
Fernando B. Naranjo ◽  
María de la Mata ◽  
Sergio I. Molina
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Interfacial Layer ◽  
Rf Sputtering ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Aln Buffer

Compact Al0.37In0.63N layers were grown by radiofrequency sputtering on bare and 15 nm-thick AlN-buffered Si (111) substrates. The crystalline quality of the AlInN layers was studied by high-resolution X-ray diffraction measurements and transmission electron microscopy. Both techniques show an improvement of the structural properties when the AlInN layer is grown on a 15 nm-thick AlN buffer. The layer grown on bare silicon exhibits a thin amorphous interfacial layer between the substrate and the AlInN, which is not present in the layer grown on the AlN buffer layer. A reduction of the density of defects is also observed in the layer grown on the AlN buffer.

Investigation of ZnFe2O4 Nanoparticles Prepared by High Energy Milling

2009 ◽  
Author(s):  
S. S. Srinivasan ◽  
N. Kislov ◽  
Yu. Emirov ◽  
D. Y. Goswami ◽  
E. K. Stefanakos
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Energy Gap ◽  
Blue Shift ◽  
High Energy ◽  
X Ray Diffraction ◽  
Force Microscopy ◽  
Atomic Force ◽  
Coefficient Estimation ◽  
Transmission Electron

Nanoparticles of Zinc Ferrite (ZnFe2O4) prepared by both wet- and dry- high-energy ball milling (HEBM), have been investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM), surface area and pore size distribution (BET) and wavelength-dependent diffuse reflectance and scattering turned into absorption coefficient estimation using the Kubelka-Munk theory. It was found that after 72 hours of HEBM, the particle size was decreased from 220 nm for the initial material to 16.5 nm and 9.4 nm for the wet- and dry-milled samples, respectively. The optical absorption analysis revealed that the energy gap is increased (blue shift) by 0.45 eV for wet-milled and decreased (“anomalous” red shift) by 0.15 eV for dry-milled samples of ZnFe2O4 as the particle size decreased.

DNA - Directed Synthesis of ZnO Nanowires

2008 ◽  
Vol 1094 ◽  
Author(s):  
Micha Jost ◽  
Petia Atanasova ◽  
Peter Gerstel ◽  
Wilfried Sigle ◽  
Peter A. van Aken ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Nitrate Solution ◽  
Zinc Nitrate ◽  
Zno Nanowires ◽  
X Ray Diffraction ◽  
Structure Directing Agent ◽  
Simple Method ◽  
Transmission Electron ◽  
Fish Sperm ◽  
Sperm Dna

AbstractIn this paper, a new and simple method for the synthesis of ZnO nanowires under very mild conditions is presented. The nanowire preparation is based on mineralization from alkaline aqueous zinc nitrate solution in the presence of fish sperm DNA as a structure-directing agent. The morphological features of the obtained structures were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), while the structural characterization of ZnO was done by X-ray diffraction.

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