MORPHOLOGICAL AND PHYSICAL PROPERTIES OF ZnO NANOSTRUCTURES GROWN ON Sb-DOPED ZnO SEEDING FILMS ANNEALED UNDER DIFFERENT ATMOSPHERES

In this work, morphological and physical properties of pyramid-like ZnO nanostructures fabricated on Sb-doped ZnO seeding films annealed under different atmospheres are extensively studied. The Sb-doped ZnO seeding films were first prepared by sol–gel spin coating technique onto glass substrate then annealed in nitrogen, air and argon followed by low-temperature hydrothermal process for ZnO nanostructures fabrication. The morphological results exhibit the growth of pyramid-like ZnO nanostructure with increasing density of the ZnO nanostructures. The crystal structure shows pyramid-like ZnO wurtzite hexagonal growth along the c-axis without any impurity phase. The growth of pyramid-like ZnO nanostructures is due to the high growth rate of (002) plane. Photoluminescence spectra exhibit the near-band-edge of all samples while the red emission appears in ZnO nanostructures after the hydrothermal process due to the imperfection in the crystal. The reflectance of ZnO nanostructures covers the visible region with the absorption edge of 375[Formula: see text]nm. The calculation shows the relevant energy band gaps in the range of 3.26–3.28[Formula: see text]eV. The difference in hydrothermally grown ZnO nanostructures is significantly affected by different annealing atmospheres.

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Optical Properties of Sn Doped ZnO Thin Film Prepared Using Sol-Gel Method for Optical Limiting Application

Al-Nahrain Journal of Science ◽

10.22401/anjs.24.3.06 ◽

2021 ◽

Vol 24 (3) ◽

pp. 38-42

Author(s):

Marwa Mudfer Alqaisi ◽

◽

Alla J. Ghazai ◽

Keyword(s):

Thin Films ◽

Zinc Oxide ◽

Optical Properties ◽

Sol Gel ◽

Visible Region ◽

Optical Limiting ◽

Pure Zinc ◽

Gel Method ◽

Sol Gel Method ◽

Doped Zno

In this work, pure Zinc oxide and tin doped Zinc oxide thin films nanoparticles with various volume concentrations of 2, 4, 6, and 8V/V% were prepared by using the sol-gel method. The optical properties were investigated by using UV-Visible spectroscope, and the value exhibits the direct allowed transition. The average of transmittance was around ~(17-23) %in visible region. The optical energy band gap was calculated with wavelength (300-900) nm for pure ZnO and Sn doped ZnO thin films which decreases with increasing concentration from 3.4 eV to 3.1 eV respectively and red shift. The real dielectric(εr) and the imaginary dielectric εiare the same behavior of the refractive index(n) the extinction coefficient (k) respectively. The optical limiting properties were studied by using an SDL laser with a wavelength of 235 nm. ZnO and doping thin films an found efficient as optic limiting and depend on the concentration of the all samples.

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Photoluminescence and Raman Studies of Annealed ZnO Nanostructures

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.501.179 ◽

2012 ◽

Vol 501 ◽

pp. 179-183 ◽

Cited By ~ 1

Author(s):

Siti Khadijah Mohd Bakhori ◽

Chuo Ann Ling ◽

Shahrom Mahmud

Keyword(s):

Optical Signal ◽

High Mode ◽

Raman Shift ◽

Near Band Edge ◽

Band Edge Emission ◽

Zno Nanostructures ◽

Zno Nanostructure ◽

Band Emission ◽

Crystallite Sizes ◽

Tem Microscopy

The influence of annealing on the optical properties of as-grown ZnO nanostructures prepared in pellets has been investigated by photoluminescence (PL) and Raman spectroscopy. The annealing temperatures of ZnO nanostructure at 600°C, 650°C and 700 °C were conducted in oxygen (O2) and nitrogen (N2) ambient. The near band edge emission (NBE) of samples recorded in the PL spectra demonstrates significant changes on optical signal whereby the NBE is redshifted after O2 annealed and became slightly higher in N2 annealed. Apart from that, weak green luminescence (GL) namely deep band emission (DBE) is observed centre at 532.95 nm (2.23 eV) and 511.00 nm (2.42 eV) for annealed in O2 and N2 respectively, whereas lower DBE observed in as-grown ZnO. On the other hand, Raman shift reveal the phonon mode of the ZnO nanostructures and the E2 (high) mode were downshifted as annealed in O2 ambient, and upshifted in N2 ambient. The downshift and upshift of the E2 (high) mode are correlated to tensile and compressive stress. Moreover the crystallite sizes were calculated from FWHM of XRD and TEM microscopy reveals the nanoplates structure of ZnO nanostructures.

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Elucidation of optoelectronic properties of the sol-gel-grown Al-doped ZnO nanostructures

Journal of Sol-Gel Science and Technology ◽

10.1007/s10971-015-3894-y ◽

2015 ◽

Vol 77 (3) ◽

pp. 642-649 ◽

Cited By ~ 1

Author(s):

M. Alam Khan ◽

Edoardo Magnone ◽

Yong-Mook Kang

Keyword(s):

Sol Gel ◽

Optoelectronic Properties ◽

Zno Nanostructures ◽

Doped Zno

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Preparation of Ni Doped ZnO-TiO2Composites and Their Enhanced Photocatalytic Activity

International Journal of Photoenergy ◽

10.1155/2014/893158 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Xiaowen Zou ◽

Xiaoli Dong ◽

Limei Wang ◽

Hongchao Ma ◽

Xinxin Zhang ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Sol Gel ◽

Visible Region ◽

Hydroxyl Groups ◽

X Ray ◽

Surface Hydroxyl ◽

Simulated Solar Light ◽

Transmission Electron ◽

Doped Zno

Herein, Ni doped ZnO-TiO2composites were prepared by facile sol-gel approach and were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-visible diffuse reflectance spectroscopy (UV-Vis DRS), X-ray photoelectron spectroscopy (XPS), and photoluminescence spectroscopy (PL). The results indicated that the Ni ions can be incorporated into the lattice of TiO2structure and replace Ti. The introduction of Ni expanded light absorption of TiO2to visible region, increased amount of surface hydroxyl groups and physically adsorbed oxygen (as the electronic scavenges), and then enhanced separation rate of photogenerated carriers. The photodegradation test of reactive brilliant blue (KN-R) under simulated solar light indicated that Ni doped ZnO-TiO2composites have better photocatalytic activities, as compared to those of TiO2and ZnO-TiO2.

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Preparation and Characterization of Cu-Doped Zno Sol-Gel Derived Optical Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.802.124 ◽

2013 ◽

Vol 802 ◽

pp. 124-128 ◽

Cited By ~ 3

Author(s):

Krisana Chongsri ◽

Siriwattana Aunpang ◽

Wicharn Techitdheera ◽

Wisanu Pecharapa

Keyword(s):

Thin Films ◽

Optical Properties ◽

Sol Gel ◽

Copper Acetate ◽

Visible Region ◽

Ambient Air ◽

Doping Content ◽

Acetate Dihydrate ◽

Cu Doping ◽

Doped Zno

In this work, we report the preparation of Cu-doped ZnOthin films by sol-gel method based on zinc acetate dihydrate (CH3COO)2Zn·2H2O, Copper acetate dihydrate Cu3(CH3COO)2·H2O) and diethanolamine (HN(CH2OH)2, DEA). The precursor solution was prepared at various Cu composition ranging from 2-20 wt%. All films were spin-coated on borosilicate substrates for several coating repetition followed by annealing process at 550 °C for 4 h in an ambient air. The structural properties of the films were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The XRD results indicate the domination of hexagonal wurtzite structure of ZnO with noticeable alternation in the XRD peak intensity upon Cu doping content. SEM results revealed the grain size shape and surface morphologies of as-prepared samples. Crucial optical properties of as-prepared films were scrutinized from their UV-Vis transmission spectra. The films are highly transparent in the visible region with more than 90 % transparency within 380 nm to 800 nm. Their corresponding band gaps indicate significant red shift with increasing Cu doping content. Overall results suggest that Cu additive play a vital role on relevant optical properties of ZnO that can be adjusted to meet the requirement for practical optoelectronics applications.

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Growth of Zn1−x CdxO nanocrystalline thin films by sol-gel method and their characterization for optoelectronic applications

Materials Science-Poland ◽

10.2478/s13536-014-0248-3 ◽

2014 ◽

Vol 32 (4) ◽

pp. 688-695 ◽

Cited By ~ 8

Author(s):

Munirah Munirah ◽

Ziaul Khan ◽

Mohd. Khan ◽

Anver Aziz

Keyword(s):

Thin Films ◽

Sol Gel ◽

Visible Region ◽

Zno Thin Films ◽

Band Edge Emission ◽

X Ray Diffraction ◽

X Ray ◽

Cd Doping ◽

Vis Spectroscopy ◽

Doped Zno

AbstractThis paper describes the growth of Cd doped ZnO thin films on a glass substrate via sol-gel spin coating technique. The effect of Cd doping on ZnO thin films was investigated using X-ray diffraction (XRD), UV-Vis spectroscopy, photoluminescence spectroscopy, I–V characteristics and field emission scanning electron microscopy (FESEM). X-ray diffraction patterns showed that the films have preferred orientation along (002) plane with hexagonal wurtzite structure. The average crystallite sizes decreased from 24 nm to 9 nm, upon increasing of Cd doping. The films transmittance was found to be very high (92 to 95 %) in the visible region of solar spectrum. The optical band gap of ZnO and Cd doped ZnO thin films was calculated using the transmittance spectra and was found to be in the range of 3.30 to 2.77 eV. On increasing Cd concentration in ZnO binary system, the absorption edge of the films showed the red shifting. Photoluminescence spectra of the films showed the characteristic band edge emission centred over 377 to 448 nm. Electrical characterization revealed that the films had semiconducting and light sensitive behaviour.

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Synthesis of ZnO Flower-Like Nanostructures on GaN Epitaxial Layer by Hydrothermal Process

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.124-126.555 ◽

2007 ◽

Vol 124-126 ◽

pp. 555-558 ◽

Cited By ~ 3

Author(s):

Jae Min Jang ◽

Sung Hak Yi ◽

Seung Kyu Choi ◽

Jeong A Kim ◽

Woo Gwang Jung

Keyword(s):

Aqueous Solution ◽

Hydrothermal Synthesis ◽

Epitaxial Layer ◽

Hydrothermal Process ◽

Xrd Analysis ◽

Zno Nanostructures ◽

Single Crystalline ◽

Zno Nanostructure

3D type flower-like ZnO nanostructure is fabricated on GaN epitaxial layer by hydrothermal synthesis. The formation of ZnO nanostructures is controlled dominantly by pH of the aqueous solution. The microstructure of flower-like ZnO nanostructure was examined by FE-SEM, XRD and FE-TEM. It is found that the shape of ZnO nanostructures are likely flower and chestnut bur shapes. FE-TEM and XRD analysis shows that ZnO nanostructures are single crystalline. Some discussion is made on the mechanism of ZnO growth in solutions with different pH.

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