scholarly journals Preparation, Characterisation and Photocatalytic Activity of La-doped ZnO Nanopowders Synthesised using Auto-combustion

2016 ◽  
Vol 59 (1) ◽  
pp. 1-10
Author(s):  
Mukhtar Ahmad ◽  
Eijaz Ahmed ◽  
Muhammad Ikram ◽  
Fezza Zafar ◽  
Niaz Ahmed Niaz ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Oxygen Demand ◽  
Combustion Method ◽  
X Ray Diffraction ◽  
Textile Mill ◽  
Treated Effluent ◽  
Vis Spectroscopy ◽  
Auto Combustion ◽  
Doped Zno ◽  
La Doped

Nanocrystalline nanoparticles of pristine ZnO and La-doped ZnO have been synthesised usinga combustion method using various concentrations of lanthanum dopant followed by calcination for 3 hat 700 °C. The crystalline structure, chemical composition and optical characteristics have been characterisedusing X-ray diffraction (XRD), scanning electron spectroscopy (SEM) attached with energy dispersiveX-ray (EDX) spectroscopy, Brunauer Emmett Teller (BET), UV-vis. spectroscopy and photoluminescence(PL) spectroscopy. Absorption spectra showed that the absorbance increased with La-doping and the blueshift observed was due to an increase in the band gap from 3.24 to 3.27 eV. The photocatalytic activitiesof the samples prepared were evaluated using the photocatalytic degradation of methyl orange (MO) underirradiation by sunlight. The textile mill effluents containing organic matter were also irradiated with sunlightinducing photocatalysis and the chemical oxygen demand (COD) of the treated effluent were investigated.The results showed that the ZnO photocatalyst doped with 1.0 at.% lanthanum exhibited four timesenhancement in the photocatalytic activity compared to pure ZnO.

Structure, luminescence and photocatalytic activity of Mg-doped ZnO nanoparticles prepared by auto combustion method

2015 ◽  
Vol 29 ◽  
pp. 372-379 ◽  
Author(s):  
Yajun Wang ◽  
Xiaoru Zhao ◽  
Libing Duan ◽  
Fenggui Wang ◽  
Hongru Niu ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Zno Nanoparticles ◽  
Combustion Method ◽  
Auto Combustion ◽  
Doped Zno ◽  
Mg Doped

Fabrication of La Doped ZnO Nanorods via a Solvothermal Route

2009 ◽  
Vol 620-622 ◽  
pp. 529-532
Author(s):  
Tie Kun Jia ◽  
Wei Min Wang ◽  
Zheng Yi Fu ◽  
Fei Huang ◽  
Hao Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Zno Nanorods ◽  
Photocatalytic Property ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Doped Zno ◽  
La Doped ◽  
Scanning Electron

La doped ZnO nanorods were synthesized via solvothermal technique using Zn(AC)2 and La(NO3)3 as starting materials. The products were characterized by X-ray diffraction (XRD), field scanning electron microscopy (FESEM) equipped with an energy dispersion X–ray (EDX) spectrometer, photoluminescence spectroscopy and UV-vis spectroscopy. The results of XRD in combination with EDS indicated that La was successful doped in ZnO. The obtained La doped ZnO sample exhibited nanorod like morphology and the diameter was about 30 nm. The photocatalytic property of La doped ZnO was evaluated by the variation of the concentration of RhB.

Photocatalytic Activities of Cobalt-Doped ZnO Nanoparticles by Hydrothermal Method

2021 ◽  
Vol 32 ◽  
pp. 33-43
Author(s):  
S. Sathiya ◽  
J. Vijayapriya ◽  
K. Parasuraman ◽  
Durairaj Benny Anburaj ◽  
S. Joshua Gnanamuthu ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Hydrothermal Process ◽  
Charge Carriers ◽  
Electronic Interaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Photocatalytic Activities ◽  
Doped Zno ◽  
Sun Light

Photocatalytically active cobalt-doped ZnO (Co: ZnO) hexagonal nanoparticles have been prepared by hydrothermal process. X-ray diffraction, SEM, FTIR and UV–vis spectroscopy confirmed that the dopant ions substitute for some of the lattice zinc ions, and furthermore, that Co2+ ion exists. The as-prepared Co: ZnO samples have an extended light absorption range compared with pure ZnO and showed highly efficient photocatalytic activity, only requiring 120 min to decompose ~90% of MB dye under sun light irradiation. The results indicated that a strong electronic interaction between the Co and ZnO was present, and that the incorporation of Co promoted the charge separation and enhanced the charge transfer ability and, at the same time, effectively inhibited the recombination of photogenerated charge carriers in ZnO, resulting in high visible light photocatalytic activity.

Role of Sm3+ Doping on Structural, Optical and Photoluminescence Properties of ZnO Nanoparticles Synthesized by Sol-gel Auto- combustion Method

2020 ◽  
Vol 5 (3) ◽  
pp. 236-251
Author(s):  
Eshwara I. Naik ◽  
Halehatty S.B. Naik ◽  
Ranganaik Viswanath
Keyword(s):  
Zno Nanoparticles ◽  
Sol Gel ◽  
Combustion Method ◽  
Content Increase ◽  
Photoluminescence Properties ◽  
Tem Analysis ◽  
Auto Combustion ◽  
Ion Doping ◽  
Doped Zno ◽  
Pl Intensity

Background: Various interesting consequences are reported on structural, optical, and photoluminescence properties of Zn1-xSmxO (x=0, 0.01, 0.03 and 0.05) nanoparticles synthesized by sol-gel auto-combustion route. Objective: This study aimed to examine the effects of Sm3+-doping on structural and photoluminescence properties of ZnO nanoparticles. Methods: Zn1-xSmxO (x=0, 0.01, 0.03 and 0.05) nanoparticles were synthesized by sol-gel auto combustion method. Results: XRD patterns confirmed the Sm3+ ion substitution through the undisturbed wurtzite structure of ZnO. The crystallite size was decreased from 24.33 to 18.46 nm with Sm3+ doping. The hexagonal and spherical morphology of nanoparticles was confirmed by TEM analysis. UV-visible studies showed that Sm3+ ion doping improved the visible light absorption capacity of Sm3+ iondoped ZnO nanoparticles. PL spectra of Sm3+ ion-doped ZnO nanoparticles showed an orange-red emission peak corresponding to 4G5/2→6HJ (J=7/2, 9/2 and 11/2) transition of Sm3+ ion. Sm3+ ion-induced PL was proposed with a substantial increase in PL intensity with a blue shift in peak upon Sm3+ content increase. Conclusion: Absorption peaks associated with doped ZnO nanoparticles were moved to a longer wavelength side compared to ZnO, with bandgap declines when Sm3+ ions concentration was increased. PL studies concluded that ZnO emission properties could be tuned in the red region along with the existence of blue peaks upon Sm3+ ion doping, which also results in enhancing the PL intensity. These latest properties related to Sm3+ ion-doped nanoparticles prepared by a cost-efficient process appear to be interesting in the field of optoelectronic applications, which makes them a prominent candidate in the form of red light-emitting diodes.

scholarly journals Y3+ substituted Sr-hexaferrites: sol-gel synthesis, structural, magnetic and electrical characterization

Cerâmica ◽  
2019 ◽  
Vol 65 (374) ◽  
pp. 274-281 ◽  
Author(s):  
S. S. Satpute ◽  
S. R. Wadgane ◽  
S. R. Kadam ◽  
D. R. Mane ◽  
R. H. Kadam
Keyword(s):  
Electron Microscopy ◽  
Sol Gel ◽  
Electrical Characterization ◽  
Combustion Method ◽  
Hexagonal Structure ◽  
Strontium Hexaferrite ◽  
X Ray Diffraction ◽  
X Ray ◽  
Morphological Studies ◽  
Auto Combustion

Abstract Y3+ substituted strontium hexaferrites having chemical composition SrYxFe12-xO19 (x= 0.0, 0.5, 1.0, 1.5) were successfully synthesized by sol-gel auto-combustion method. The structural and morphological studies of prepared samples were investigated by using X-ray diffraction technique, energy dispersive X-ray spectroscopy, field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy. The X-ray diffraction pattern confirmed the single-phase hexagonal structure of yttrium substituted strontium ferrite and the lattice parameters a and c increased with the substitution of Y3+ ions. The crystallite size also varied with x content from 60 to 80 nm. The morphology was studied by FE-SEM, and the grain size of nanoparticles ranged from 44 to 130 nm. The magnetic properties were investigated by using vibrating sample magnetometer. The value of saturation magnetization decreased from 49.60 to 35.40 emu/g. The dielectric constant decreased non-linearly whereas the electrical dc resistivity increased with the yttrium concentration in strontium hexaferrite.

scholarly journals Green synthesis and characterization of hexaferrite strontium-perovskite strontium photocatalyst nanocomposites

2020 ◽  
Vol 43 (1) ◽  
pp. 26-42 ◽  
Author(s):  
Zahra Hajian Karahroudi ◽  
Kambiz Hedayati ◽  
Mojtaba Goodarzi
Keyword(s):  
Magnetic Properties ◽  
Green Synthesis ◽  
Sol Gel ◽  
Synthesis Method ◽  
Combustion Method ◽  
Lemon Juice ◽  
X Ray Diffraction ◽  
X Ray ◽  
Auto Combustion

AbstractThis study presents a preparation of SrFe12O19– SrTiO3 nanocomposite synthesis via the green auto-combustion method. At first, SrFe12O19 nanoparticles were synthesized as a core and then, SrTiO3 nanoparticles were prepared as a shell for it to manufacture SrFe12O19–SrTiO3 nanocomposite. A novel sol-gel auto-combustion green synthesis method has been used with lemon juice as a capping agent. The prepared SrFe12O19–SrTiO3 nanocomposites were characterized by using several techniques to characterize their structural, morphological and magnetic properties. The crystal structures of the nanocomposite were investigated via X-ray diffraction (XRD). The morphology of SrFe12O19– SrTiO3 nanocomposite was studied by using a scanning electron microscope (SEM). The elemental composition of the materials was analyzed by an energy-dispersive X-ray (EDX). Magnetic properties and hysteresis loop of nanopowder were characterized via vibrating sample magnetometer (VSM) in the room temperature. Fourier transform infrared spectroscopy (FTIR) spectra of the samples showed the molecular bands of nanoparticles. Also, the photocatalytic behavior of nanocomposites has been checked by the degradation of azo dyes under irradiation of ultraviolet light.

Photocatalytic Activity of Fe-Doped ZnO/Montmorillonite Nanocomposite for Degradation of Malachite Green

2015 ◽  
Vol 827 ◽  
pp. 19-24 ◽  
Author(s):  
Nur Afifah ◽  
Nadia Febiana Djaja ◽  
Rosari Saleh
Keyword(s):  
Photocatalytic Activity ◽  
Malachite Green ◽  
Organic Dyes ◽  
Uv Light ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Spin Resonance ◽  
Doped Zno ◽  
Co Precipitation

In this study, the photocatalytic activity of pure Fe- doped ZnO and Fe- doped ZnO/Montmorillonite nanocomposite has been investigated for the degradation of malachite green under UV light irradiation. Both photocatalysts were synthesized using co-precipitation method and characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, Fourier-transform infrared absorption, and electron spin resonance. The results showed that the photocatalytic efficiency is better in the presence of montmorillonite compared to pure Fe- doped ZnO. To detect the possible reactive species involved in degradation of organic dyes control experiments with introducing scavengers into the solution of organic dyes were carried out. It is found that electron plays an important role in the degradation of malachite green.

scholarly journals Photocatalytic Performance of ZnO: Al Films under Different Light Sources

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Prashant Pradhan ◽  
Juan Carlos Alonso ◽  
Monserrat Bizarro
Keyword(s):  
White Light ◽  
Irradiation Time ◽  
Zno Films ◽  
Light Sources ◽  
X Ray Diffraction ◽  
Treatment Processes ◽  
Vis Spectroscopy ◽  
Doped Zno ◽  
Very High ◽  
High Degradation Rate

ZnO and Al doped ZnO films were produced by spray pyrolysis. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-vis spectroscopy, and photoluminescence. Their photocatalytic activity was evaluated by the decomposition of the methyl orange dye using different light sources: ultraviolet light, artificial white light, and direct sunlight. The films were also tested under darkness for comparison. The ZnO films were able to degrade the test pollutant under UV and sunlight in more than a 60% after 180 min of irradiation and a scarce degradation was obtained using white light. However, the Al doped ZnO films presented a very high degradation rate not only under UV and sunlight (100% degradation), but also under white light (90% degradation after the same irradiation time). An unexpected high degradation was also obtained in the dark, which indicates that a nonphotonic process is taking place parallel to the photocatalytic process. This can be due to the extra electrons—provided by the aluminum atoms—that migrate to the surface and produce radicals favoring the decomposition process even in the dark. The high activity achieved by the ZnO: Al films under natural conditions can be potentially applied to water treatment processes.

The Preparation and Photocatalytic Activity of SWNTs Doped ZnO/TiO2 Compound Films

2010 ◽  
Vol 97-101 ◽  
pp. 1611-1615 ◽  
Author(s):  
Qing Wang ◽  
Xin Li Li ◽  
Wei Nie ◽  
Yong Mei Xia ◽  
Jian Feng Dai
Keyword(s):  
Photocatalytic Activity ◽  
Absorption Spectra ◽  
Sol Gel ◽  
Composite Films ◽  
Wavelength Region ◽  
Tio2 Films ◽  
X Ray Diffraction ◽  
Sol Gel Process ◽  
Doped Zno ◽  
Walled Carbon Nanotubes

The ZnO/TiO2 composite films were deposited over glass using spin coating technique by sol-gel process. Single-walled carbon nanotubes (SWNTs) were used to modify the ZnO/TiO2 films successfully in this paper. The structure and composition of the ZnO/TiO2 composite and SWNTs doped ZnO/TiO2 composite were characterized by X-ray diffraction (XRD). The morphology of samples was characterized by scanning electron microscopy (SEM). The photocatalytic activity was investigated by photocatalytic degradation of aqueous methyl orange under ultraviolet (UV) radiation. The UV-vis absorption spectra of the ZnO/TiO2 films and SWNTs doped ZnO/TiO2 films in the wavelength region 200~800 nm were obtained. The results indicate that the SWNTs addition can decrease the grain size of ZnO/TiO2, which can enhance the photocatalytic activity. UV-vis absorption spectra of SWNTs-ZnO/TiO2 showed obvious blue shifts compared with ZnO/TiO2. The optimal amount of doping SWNTs is 1% according to this research. The enhanced mechanism of the SWNTs for the photocatalytic activity in ZnO/TiO2 films was analyzed in this article.

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