Experimentally realization of dual nonlinear dielectric resonance and electromagnetic characteristics of Manganese-doped ZnO NPs in X-Band

ZnO/MWCNTs hybrid and doped with different concentration of Nickel element prepared by using Sol-gel been technique reported. All samples were prepared and characterized by X-Ray Diffraction Analysis (XRD), Energy Dispersive X-ray Spectroscopy (EDS), Fourier-Transform Infrared Spectroscopy (FTIR), Field-Emission Scanning Electron Microscopy (FE-SEM), and UV-Vis spectroscopy have been identified the structural, optical and morphological properties. X-ray diffraction showed the polycrystalline nature with hexagonal wutzite structure of hybrid and doped with Nickel. The crystalline size of the hybrid nanostructure was increasing from 23.73 nm to 34.59 nm. Besides, the UV-Vis spectroscopy showed a significant decrease in the band gap values from 2.97 eV to 2.01 eV. Whereas the FE-SEM analysis confirm the formation spherical shapes of ZnO NPs deposited on cylindrical tubes representing the MWCNTs. The antibacterial activity reveals that the inhibition zone of Ni doped-ZnO/MWCNTs hybrid was 28.5 mm, 26.5 mm toward E. coli and S. aureus bacteria, respectively.

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Investigation on electromagnetic characteristics, microwave absorption, thermal and mechanical properties of ferromagnetic cobalt–polystyrene composites in the X-band (8.4–12.4 GHz)

RSC Advances ◽

10.1039/c5ra26489h ◽

2016 ◽

Vol 6 (17) ◽

pp. 13846-13857 ◽

Cited By ~ 24

Author(s):

Azizurrahaman Ansari ◽

Mohammad Jaleel Akhtar

Keyword(s):

Mechanical Properties ◽

Microwave Absorption ◽

Wide Band ◽

Thermal And Mechanical Properties ◽

Microwave Absorbers ◽

X Band ◽

Electromagnetic Characteristics ◽

Ferromagnetic Cobalt

The electromagnetic, thermal and mechanical properties of ferromagnetic cobalt–polystyrene composites in the X-band (8.4–12.4 GHz) are investigated in order to explore their usage for wide band microwave absorbers.

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Antibacterial Activity of Ag-Doped TiO2 and Ag-Doped ZnO Nanoparticles

International Journal of Photoenergy ◽

10.1155/2018/5927485 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7 ◽

Cited By ~ 19

Author(s):

Gebretinsae Yeabyo Nigussie ◽

Gebrekidan Mebrahtu Tesfamariam ◽

Berhanu Menasbo Tegegne ◽

Yemane Araya Weldemichel ◽

Tesfakiros Woldu Gebreab ◽

...

Keyword(s):

Antibacterial Activity ◽

Zno Nanoparticles ◽

Pathogenic Bacteria ◽

Anatase Phase ◽

Sol Gel ◽

X Ray Diffraction ◽

Zno Nps ◽

Sem Images ◽

X Ray ◽

Doped Zno

We report in this paper antibacterial activity of Ag-doped TiO2 and Ag-doped ZnO nanoparticles (NPs) under visible light irradiation synthesized by using a sol-gel method. Structural, morphological, and basic optical properties of these samples were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectrum, and UV-Vis reflectance. Room temperature X-ray diffraction analysis revealed that Ag-doped TiO2 has both rutile and anatase phases, but TiO2 NPs only have the anatase phase. In both ZnO and Ag-doped ZnO NPs, the hexagonal wurtzite structure was observed. The morphologies of TiO2 and ZnO were influenced by doping with Ag, as shown from the SEM images. EDX confirms that the samples are composed of Zn, Ti, Ag, and O elements. UV-Vis reflectance results show decreased band gap energy of Ag-doped TiO2 and Ag-doped ZnO NPs in comparison to that of TiO2 and ZnO. Pathogenic bacteria, such as Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli, were used to assess the antibacterial activity of the synthesized materials. The reduction in the viability of all the three bacteria to zero using Ag-doped ZnO occurred at 60 μg/mL of culture, while Ag-doped TiO2 showed zero viability at 80 μg/mL. Doping of Ag on ZnO and TiO2 plays a vital role in the increased antibacterial activity performance.

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Effect of silver doping on structural and photocatalytic circumstances of ZnO nanoparticles

Iraqi Journal of Nanotechnology ◽

10.47758/ijn.vi1.22 ◽

2020 ◽

pp. 13-20

Author(s):

Luma Ahmed ◽

Eitemad S. Fadhil ◽

Ayad F. Mohammed

Keyword(s):

Zno Nanoparticles ◽

Precipitation Method ◽

Methyl Green ◽

Zno Nanoparticle ◽

Zno Nps ◽

Force Microscopy ◽

Ft Ir ◽

Doped Zno ◽

Co Precipitation ◽

Artificial Uv

This article describes the synthesis of ZnO nanoparticles (Nps) using the co-precipitation method and then calcinated at 500oC for 2 h. The photo activity of ZnO nanoparticles was examined in photo decolorization of methyl green dye under artificial UV -A light. This prepared photocatalyst (ZnO Np) was modified his surface by 2% Ag doped using the photo deposition method under inert gas for 3h. The characterization of undoped and 2% Ag doped ZnO Nps were estimated by Fourier-transform infrared spectroscopy (FT-IR), X-ray Diffraction (XRD), and Atomic force microscopy (AFM). In FT-IR analysis, the new peaks occurred around 624-778 cm-1 confirmed the Ag really is doped on prepared ZnO Np. Based on data from XRD, the mean crystal size was reduced with doped the 2% Ag. The AFM images for the prepared photocatalysts ensure that the shapes of all samples are semi-spherical with nanometer size. Series of kinetics experiments were performed for the photocatalytic decolourization of methyl green dye using undoped and 2% Ag doped ZnO nanoparticle and found to be pseudo-first-order kinetics.

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Enhanced Photocatalytic Performance of Al-Doped ZnO NPs-Reduced Graphene Oxide Nanocomposite for Removing of Methyl Orange Dye from Water Under Visible-Light Irradiation

Journal of Inorganic and Organometallic Polymers and Materials ◽

10.1007/s10904-018-0940-6 ◽

2018 ◽

Vol 28 (6) ◽

pp. 2677-2688 ◽

Cited By ~ 4

Author(s):

S. Asghar Khayatian ◽

Ahmad Kompany ◽

Nasser Shahtahmassebi ◽

A. Khorsand Zak

Keyword(s):

Graphene Oxide ◽

Methyl Orange ◽

Visible Light ◽

Reduced Graphene Oxide ◽

Visible Light Irradiation ◽

Photocatalytic Performance ◽

Zno Nps ◽

Reduced Graphene ◽

Methyl Orange Dye ◽

Doped Zno

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Effects of Ambience on Thermal-Diffusion Type Ga-doping Process for ZnO Nanoparticles

Coatings ◽

10.3390/coatings12010057 ◽

2022 ◽

Vol 12 (1) ◽

pp. 57

Author(s):

Md Maruful Islam ◽

Toshiyuki Yoshida ◽

Yasuhisa Fujita

Keyword(s):

Sheet Resistance ◽

Thermal Diffusion ◽

Arc Discharge ◽

Atmospheric Effects ◽

Zno Nanoparticle ◽

Zno Nps ◽

Diffusion Type ◽

Transistor Channel ◽

Doped Zno ◽

Ga Doping

Various annealing atmospheres were employed during our unique thermal-diffusion type Ga-doping process to investigate the surface, structural, optical, and electrical properties of Ga-doped zinc oxide (ZnO) nanoparticle (NP) layers. ZnO NPs were synthesized using an arc-discharge-mediated gas evaporation method, followed by Ga-doping under open-air, N2, O2, wet, and dry air atmospheric conditions at 800 °C to obtain the low resistive spray-coated NP layers. The I–V results revealed that the Ga-doped ZnO NP layer successfully reduced the sheet resistance in the open air (8.0 × 102 Ω/sq) and wet air atmosphere (8.8 × 102 Ω/sq) compared with un-doped ZnO (4.6 × 106 Ω/sq). Humidity plays a key role in the successful improvement of sheet resistance during Ga-doping. X-ray diffraction patterns demonstrated hexagonal wurtzite structures with increased crystallite sizes of 103 nm and 88 nm after doping in open air and wet air atmospheres, respectively. The red-shift of UV intensity indicates successful Ga-doping, and the atmospheric effects were confirmed through the analysis of the defect spectrum. Improved electrical conductivity was also confirmed using the thin-film-transistor-based structure. The current controllability by applying the gate electric-field was also confirmed, indicating the possibility of transistor channel application using the obtained ZnO NP layers.

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Influence of surfactant-tailored Mn-doped ZnO nanoparticles on ROS production and DNA damage induced in murine fibroblast cells

Scientific Reports ◽

10.1038/s41598-020-74816-0 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Traian Popescu ◽

Christien Oktaviani Matei ◽

Ioana Dorina Vlaicu ◽

Ioan Tivig ◽

Andrei Cristian Kuncser ◽

...

Keyword(s):

Specific Surface ◽

Surface Area ◽

Zno Nanoparticles ◽

In Vitro Toxicity ◽

Fibroblast Cells ◽

Zno Nps ◽

Mn Doping ◽

Doped Zno ◽

Mn Doped

Abstract The present study concerns the in vitro oxidative stress responses of non-malignant murine cells exposed to surfactant-tailored ZnO nanoparticles (NPs) with distinct morphologies and different levels of manganese doping. Two series of Mn-doped ZnO NPs were obtained by coprecipitation synthesis method, in the presence of either polyvinylpyrrolidone (PVP) or sodium hexametaphosphate (SHMTP). The samples were investigated by powder X-ray Diffraction, Transmission Electron Microscopy, Fourier-Transform Infrared and Electron Paramagnetic Resonance spectroscopic methods, and N2 adsorption–desorption analysis. The observed surfactant-dependent effects concerned: i) particle size and morphology; ii) Mn-doping level; iii) specific surface area and porosity. The relationship between the surfactant dependent characteristics of the Mn-doped ZnO NPs and their in vitro toxicity was assessed by studying the cell viability, intracellular reactive oxygen species (ROS) generation, and DNA fragmentation in NIH3T3 fibroblast cells. The results indicated a positive correlation between the specific surface area and the magnitude of the induced toxicological effects and suggested that Mn-doping exerted a protective effect on cells by diminishing the pro-oxidative action associated with the increase in the specific BET area. The obtained results support the possibility to modulate the in vitro toxicity of ZnO nanomaterials by surfactant-controlled Mn-doping.

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Investigations on microstructure, optical, magnetic, photocatalytic, and dielectric behaviours of pure and Co-doped ZnO NPs

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-020-03192-2 ◽

2020 ◽

Vol 31 (8) ◽

pp. 6360-6371 ◽

Cited By ~ 4

Author(s):

M. A. Majeed Khan ◽

Rahul Siwach ◽

Sushil Kumar ◽

Maqusood Ahmed ◽

Jahangeer Ahmed

Keyword(s):

Zno Nps ◽

Doped Zno ◽

Co Doped

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High Performance Top-Emission Quantum Dot Light-Emitting Diodes with Mg-Doped ZnO Nanoparticles Used as an Electron Transport Layer

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.19230 ◽

2021 ◽

Vol 21 (7) ◽

pp. 3747-3752

Author(s):

Bada Kim ◽

Dohyeong Lee ◽

Boram Hwang ◽

Yebin Eun ◽

Mi-Young Ha ◽

...

Keyword(s):

Electron Transport ◽

Quantum Dot ◽

Transport Layer ◽

Electron Transport Layer ◽

Maximum Luminance ◽

Zno Nps ◽

Light Emitting ◽

Mg Doping ◽

Doped Zno ◽

Mg Doped

In this paper, we reported superior performance of solution-processed top-emission quantum dot light-emitting diodes (TE-QLEDs) with Mg-doped ZnO nanoparticle (NP) electron transport layer (ETL). The Mg-doped ZnO NPs were synthesized by the sol-gel method. Transmission electron microscopy (TEM) analysis of the Mg-doped ZnO NPs with 0 wt%, 5 wt%, 10 wt%, and 15 wt% Mg-doping concentrations revealed average diameters of 5.86 nm, 5.33 nm, 4.52 nm, and 4.37 nm, respectively. The maximum luminance, the current efficiency, and external quantum efficiency (EQE) were 178,561.8 cd/m2, 56.0 cd/A, and 14.43%, respectively. However, for the best performance of TE-QLED without Mg-doping in the ZnO NPs, the maximum luminance was only 101,523.4 cd/m2, the luminous efficiency was 27.8 cd/A, and the EQE was 6.91%. The improvement of the performance is attributed to the suppression of electron transfer by an increase in the energy barrier between the cathode and Mg-doped ZnO NP ETL and the reduction in the Hall mobility of electron with increasing the Mg-doping in the ZnO NPs, resulting in the enhanced charge balance in the quantum dot (QD) emitting layer (EML).

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