Synthesis, Characterization, and Photocatalytic Tests of N-Doped Zinc Oxide: A New Interesting Photocatalyst

Fast and simple synthetic methods for the preparation of bare and N-doped zinc oxide, involving a stirring or microwave assisted process, are proposed. All samples were characterized by XRD analysis, BET, and DRS-UV-Vis spectroscopy. The photocatalytic activity of these nanostructured oxides was investigated using phenol and 2,4-dichlorophenol as model molecules under UV-A and visible light irradiation. N-doping in ZnO nanostructures provided a significant increase in phenol and 2,4-dichlorophenol degradation rate under Vis light, leading to a degradation rate higher than that obtained with bare ZnO. The release of chlorine as chloride ions from 2,4-dichlorophenol with N-doped ZnO was faster achieved as well and complete dechlorination was reached within 2 h of irradiation (N-doped ZnO) instead of 3 h (bare ZnO).

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Surfactant-Free Microwave-Assisted Synthesis of Fe-Doped ZnO Nanostars as Photocatalyst for Degradation of Tropaeolin O in Water under Visible Light

Journal of Nanomaterials ◽

10.1155/2015/190747 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 7

Author(s):

Tsz-Lung Kwong ◽

Ka-Fu Yung

Keyword(s):

Visible Light ◽

Photocatalytic Degradation ◽

Irradiation Time ◽

Catalyst Loading ◽

Orthogonal Experimental Design ◽

Microwave Assisted Synthesis ◽

X Ray ◽

Microwave Assisted ◽

Vis Spectroscopy ◽

Doped Zno

Iron-doped zinc oxide nanostar was synthesized by the microwave-assisted surfactant-free hydrolysis method. The as-synthesized Fe-doped ZnO nanostars catalyst was fully characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), and diffuse reflectance UV-vis spectroscopy (UV-DRA). The photocatalytic activity of the photocatalyst was investigated for the photocatalytic degradation of Tropaeolin O under visible light irradiation. It is observed that the doping of Fe ions enhances the absorption of the visible light and thus the photocatalytic degradation rate of Tropaeolin O would increase. Despite the Taguchi orthogonal experimental design method, the photocatalytic conversion could be achieved at 99.8% in the Fe-doped ZnO catalyzed photodegradation reaction under the optimal reaction conditions of catalyst loading (30 mg), temperature (60°C), light distance (0 cm), initial pH (pH = 9), and irradiation time (3 h). The Fe-doped ZnO photocatalyst can also be easily recovered and directly reused for eight cycles with over 70% conversion.

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Effect of Ag Doping on Properties of Al–Doped ZnO Nanoparticles Varies as Zn1-X-YAgxALYO

Material Science Research India ◽

10.13005/msri/140210 ◽

2017 ◽

Vol 14 (2) ◽

pp. 146-152

Author(s):

Neha Sharma ◽

Sanjayay Kumar

Keyword(s):

Zno Nanoparticles ◽

Spherical Shape ◽

Xrd Analysis ◽

Crystalline Size ◽

X Ray Diffraction ◽

X Ray ◽

In Doping ◽

Vis Spectroscopy ◽

Doped Zno

In present study, undoped ZnO, Zn0.8Ag0.2O, Zn0.8Al0.2O and Zn0.6Al0.2Ag0.2O samples are synthesized by simple solution method. X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX) and UV-visible (UV-Vis) spectroscopy are used to perform the characterization of undoped, doped and codoped samples. XRD analysis is exposed that hexagonal wurtzite crystalline structure obtained for undoped, doped and codoped samples without any extra representation of impurity phases. The crystalline size is when evaluated by using Scherrer, It has 44, 49, 41and 37nm for undoped ZnO, Zn0.8Ag0.2O, Zn0.8Al0.2O and Zn0.6Al0.2Ag0.2O samples. Similarly, the crystalline size and strain are also evaluated by Williamson hall (W-H) and size strain plot (SSP) for the undoped, doped and codoped nanoparticles. The evaluated crystalline size by SSP is three times greater than the result of the scherrer method. The SEM exposes that surface morphology of nanoparticle samples, in this case is the formation of large agglomeration in spherical shape with nanocrystallites of undoped and doped ZnO with apparent and definite boundaries. EDX points out the replacement of Al2+ and Ag+ with Zn2+ in ZnO matrix and consequences in the development of single-phase Zn1−x−yAgxAlyO. The blueshift is shown in UV-Vis absorption spectra because the band gap value increases with the increase in doping, except Ag+ doped ZnO nanoparticles.

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Manganese-Doped Zinc Oxide Nanostructures as Potential Scaffold for Photocatalytic and Fluorescence Sensing Applications

Chemosensors ◽

10.3390/chemosensors8040120 ◽

2020 ◽

Vol 8 (4) ◽

pp. 120

Author(s):

Deepika Thakur ◽

Anshu Sharma ◽

Abhishek Awasthi ◽

Dharmender Singh Rana ◽

Dilbag Singh ◽

...

Keyword(s):

Zinc Oxide ◽

Zno Nanostructures ◽

Zinc Oxide Nanostructures ◽

Fluorescence Sensing ◽

X Ray ◽

Sensing Applications ◽

Oxide Nanostructures ◽

Vis Spectroscopy ◽

Doped Zno ◽

Mn Doped

Herein, we report the photocatalytic and fluorescence sensing applications of manganese-doped zinc oxide nanostructures synthesized by a solution combustion technique, using zinc nitrate as an oxidizer and urea as a fuel. The synthesized Mn-doped ZnO nanostructures have been analyzed in terms of their surface morphology, phase composition, elemental analysis, and optical properties with the help of scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), and UV-Visible (UV-Vis) spectroscopy. A careful observation of the SEM micrograph reveals that the synthesized material was porous and grown in very high density. Due to a well-defined porous structure, the Mn-doped ZnO nanostructures can be used for the detection of ciprofloxacin, which was found to exhibit a significantly low limit of detection (LOD) value i.e., 10.05 µM. The synthesized Mn-doped ZnO nanostructures have been further analyzed for interfering studies, which reveals that the synthesized sensor material possesses very good selectivity toward ciprofloxacin, as it detects selectively even in the presence of other molecules. The synthesized Mn-doped ZnO nanostructures have been further analyzed for the photodegradation of methyl orange (MO) dye. The experimental results reveal that Mn-doped ZnO behaves as an efficient photocatalyst. The 85% degradation of MO has been achieved in 75 min using 0.15 g of Mn-doped ZnO nanostructures. The observed results clearly confirmed that the synthesized Mn-dopedZnO nanostructures are a potential scaffold for the fabrication of sensitive and robust chemical sensors as well as an efficient photocatalyst.

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Green and Economic Fabrication of Zinc Oxide (ZnO) Nanorods as a Broadband UV Blocker and Antimicrobial Agent

Nanomaterials ◽

10.3390/nano10030530 ◽

2020 ◽

Vol 10 (3) ◽

pp. 530 ◽

Cited By ~ 5

Author(s):

Seyedeh-Masoumeh Taghizadeh ◽

Neha Lal ◽

Alireza Ebrahiminezhad ◽

Fatemeh Moeini ◽

Mostafa Seifan ◽

...

Keyword(s):

Zinc Oxide ◽

Large Scale ◽

Average Length ◽

Zno Nanorods ◽

Waste Product ◽

Antibacterial Properties ◽

Xrd Analysis ◽

Controlled Synthesis ◽

Vis Spectroscopy ◽

Prepared Nanorods

Zinc oxide (ZnO) nanoparticles have gained widespread interest due to their unique properties, making them suitable for a range of applications. Several methods for their production are available, and of these, controlled synthesis techniques are particularly favourable. Large-scale culturing of Chlorella vulgaris produces secretory carbohydrates as a waste product, which have been shown to play an important role in directing the particle size and morphology of nanoparticles. In this investigation, ZnO nanorods were produced through a controlled synthesis approach using secretory carbohydrates from C. vulgaris, which presents a cost-effective and sustainable alternative to the existing techniques. Fourier transform infrared (FTIR) spectroscopy, X-ray powder diffraction (XRD) analysis, transmission electron microscopy (TEM), and UV-Vis spectroscopy were used to characterise the nanorods. The prepared nanorods exhibited a broad range of UV absorption, which suggests that the particles are a promising broadband sun blocker and are likely to be effective for the fabrication of sunscreens with protection against both UVB (290–320 nm) and UVA (320–400 nm) radiations. The antimicrobial activity of the prepared nanorods against Gram-positive and Gram-negative bacteria was also assessed. The nanostructures had a crystalline structure and rod-like appearance, with an average length and width of 150 nm and 21 nm, respectively. The nanorods also demonstrated notable antibacterial activity, and 250 μg/mL was determined to be the most effective concentration. The antibacterial properties of the ZnO nanorods suggest its suitability for a range of antimicrobial uses, such as in the food industry and for various biomedical applications.

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Gallium Concentration Optimisation of Gallium Doped Zinc Oxide for Improvement of Optical Properties

Latvian Journal of Physics and Technical Sciences ◽

10.2478/lpts-2021-0004 ◽

2021 ◽

Vol 58 (1) ◽

pp. 33-43

Author(s):

A. Spustaka ◽

M. Senko ◽

D. Millers ◽

I. Bite ◽

K. Smits ◽

...

Keyword(s):

Zinc Oxide ◽

Luminescence Intensity ◽

Xrd Analysis ◽

Peak Position ◽

Concentration Effects ◽

Wurtzite Phase ◽

Gallium Concentration ◽

Luminescence Peak ◽

Optimal Value ◽

Doped Zno

AbstractThe near-band luminescence of doped ZnO is promising for advanced scintillators; however, the dopant type and concentration effects require a detailed study. Undoped and Ga-doped ZnO nanopowders were prepared by a microwave-assisted solvothermal method and the gallium concentration effect on luminescence properties was studied. The near-band luminescence peak position dependence on gallium concentration was observed. Near-band luminescence intensity versus defect luminescence intensity ratio was explored for different gallium concentrations and the optimal value was determined. Samples were prepared with dopant concentrations between 0.2 and 1.5 at%, XRD analysis confirmed that samples contained only zinc oxide hexagonal wurtzite phase. The results of the research showed that ZnO:Ga containing 0.9 at.% gallium was promising for scintillators.

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Polymer-Based Graphene Derivatives and Microwave-Assisted Silver Nanoparticles Decoration as a Potential Antibacterial Agent

Nanomaterials ◽

10.3390/nano10112269 ◽

2020 ◽

Vol 10 (11) ◽

pp. 2269

Author(s):

Angelo Nicosia ◽

Fabiana Vento ◽

Anna Lucia Pellegrino ◽

Vaclav Ranc ◽

Anna Piperno ◽

...

Keyword(s):

Electron Microscopy ◽

Silver Nanoparticles ◽

Microwave Irradiation ◽

Bacterial Load ◽

Antibacterial Properties ◽

Synthetic Methods ◽

Specific Substrate ◽

Microwave Assisted ◽

Vis Spectroscopy ◽

Graphene Derivatives

Nanocomposites obtained by the decoration of graphene-based materials with silver nanoparticles (AgNPs) have received increasing attention owing to their antimicrobial activity. However, the complex synthetic methods for their preparation have limited practical applications. This study aims to synthesize novel NanoHybrid Systems based on graphene, polymer, and AgNPs (namely, NanoHy-GPS) through an easy microwave irradiation approach free of reductants and surfactants. The polymer plays a crucial role, as it assures the coating layer/substrate compatibility making the platform easily adaptable for a specific substrate. AgNPs’ loading (from 5% to 87%) can be tuned by the amount of Silver salt used during the microwave-assisted reaction, obtaining spherical AgNPs with average sizes of 5–12 nm homogeneously distributed on a polymer-graphene nanosystem. Interestingly, microwave irradiation partially restored the graphene sp2 network without damage of ester bonds. The structure, morphology, and chemical composition of NanoHy-GPS and its subunits were characterized by means of UV-vis spectroscopy, thermal analysis, differential light scattering (DLS), Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive X-ray analysis (EDX), Atomic Force Microscopy (AFM), and High-Resolution Transmission Electron Microscopy (HRTEM) techniques. A preliminary qualitative empirical assay against the typical bacterial load on common hand-contacted surfaces has been performed to assess the antibacterial properties of NanoHy-GPS, evidencing a significative reduction of bacterial colonies spreading.

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Influence of Calcination Temperature on Crystal Growth and Optical Characteristics of Eu3+ Doped ZnO/Zn2SiO4 Composites Fabricated via Simple Thermal Treatment Method

Crystals ◽

10.3390/cryst11020115 ◽

2021 ◽

Vol 11 (2) ◽

pp. 115

Author(s):

Suhail Huzaifa Jaafar ◽

Mohd Hafiz Mohd Zaid ◽

Khamirul Amin Matori ◽

Sidek Hj. Ab Aziz ◽

Halimah Mohamed Kamari ◽

...

Keyword(s):

Thermal Treatment ◽

Band Gap ◽

Calcination Temperature ◽

Emission Intensity ◽

Emission Spectra ◽

Treatment Method ◽

Absorption Bands ◽

Vis Spectroscopy ◽

Doped Zno ◽

Zno Crystal

This research paper proposes the usage of a simple thermal treatment method to synthesis the pure and Eu3+ doped ZnO/Zn2SiO4 based composites which undergo calcination process at different temperatures. The effect of calcination temperatures on the structural, morphological, and optical properties of ZnO/Zn2SiO4 based composites have been studied. The XRD analysis shows the existence of two major phases which are ZnO and Zn2SiO4 crystals and supported by the finding in the FT-IR. The FESEM micrograph further confirms the existence of both ZnO and Zn2SiO4 crystal phases, with progress in the calcination temperature around 700–800 °C which affects the existence of the necking-like shape particle. Absorption humps discovered through UV-Vis spectroscopy revealed that at the higher calcination temperature effects for higher absorption intensity while absorption bands can be seen at below 400 nm with dropping of absorption bands at 370–375 nm. Two types of band gap can be seen from the energy band gap analysis which occurs from ZnO crystal and Zn2SiO4 crystal progress. It is also discovered that for Eu3+ doped ZnO/Zn2SiO4 composites, the Zn2SiO4 crystal (5.11–4.71 eV) has a higher band gap compared to the ZnO crystal (3.271–4.07 eV). While, for the photoluminescence study, excited at 400 nm, the emission spectra of Eu3+ doped ZnO/Zn2SiO4 revealed higher emission intensity compared to pure ZnO/Zn2SiO4 with higher calcination temperature exhibit higher emission intensity at 615 nm with 700 °C being the optimum temperature. The emission spectra also show that the calcination temperature contributed to enhancing the emission intensity.

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Zinc oxide nanoparticles using plant Lawsonia inermis and their mosquitocidal, antimicrobial, anticancer applications showing moderate side effects

Scientific Reports ◽

10.1038/s41598-021-88164-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Pandiyan Amuthavalli ◽

Jiang-Shiou Hwang ◽

Hans-Uwe Dahms ◽

Lan Wang ◽

Jagannathan Anitha ◽

...

Keyword(s):

Zinc Oxide ◽

Zinc Oxide Nanoparticles ◽

Mosquito Control ◽

Xrd Analysis ◽

Microbial Pathogens ◽

Oxide Nanoparticles ◽

Lawsonia Inermis ◽

Zno Nps ◽

Vector Borne Diseases ◽

Substantial Problem

AbstractMicrobes or parasites spread vector-borne diseases by mosquitoes without being affected themselves. Insecticides used in vector control produce a substantial problem for human health. This study synthesized zinc oxide nanoparticles (ZnO NPs) using Lawsonia inermis L. and were characterized by UV–vis, FT-IR, SEM with EDX, and XRD analysis. Green synthesized ZnO NPs were highly toxic against Anopheles stephensi, whose lethal concentrations values ranged from 5.494 ppm (I instar), 6.801 ppm (II instar), 9.336 ppm (III instar), 10.736 ppm (IV instar), and 12.710 ppm (pupae) in contrast to L. inermis treatment. The predation efficiency of the teleost fish Gambusia affinis and the copepod Mesocyclops aspericornis against A. stephensi was not affected by exposure at sublethal doses of ZnO NPs. The predatory potency for G. affinis was 45 (I) and 25.83% (IV), copepod M. aspericornis was 40.66 (I) and 10.8% (IV) while in an ZnO NPs contaminated environment, the predation by the fish G. affinis was boosted to 71.33 and 34.25%, and predation of the copepod M. aspericornis was 60.35 and 16.75%, respectively. ZnO NPs inhibited the growth of several microbial pathogens including the bacteria (Escherichia coli and Bacillus subtilis) and the fungi (Alternaria alternate and Aspergillus flavus), respectively. ZnO NPs decreased the cell viability of Hep-G2 with IC50 value of 21.63 µg/mL (R2 = 0.942; P < 0.001) while the concentration increased from 1.88 to 30 µg/mL. These outcomes support the use of L. inermis mediated ZnO NPs for mosquito control and drug development.

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Microwave-Assisted Preparation of Molecularly Imprinted Monolith Combining Imidazolium Ionic Liquid and POSS for Enhanced Extraction of Baicalin-Like Compounds in Scutellaria Baicalensis by means of In-Capillary SPME Followed by on-line LC and off-line LC-MS/MS

New Journal of Chemistry ◽

10.1039/d0nj06254e ◽

2021 ◽

Author(s):

Xiaohan Zhang ◽

Le Gao ◽

Liying Niu ◽

Xiaodong Bi

Keyword(s):

Ionic Liquid ◽

Molecularly Imprinted Polymers ◽

Scutellaria Baicalensis ◽

Synthetic Methods ◽

Imidazolium Ionic Liquid ◽

Molecularly Imprinted ◽

Imprinted Polymers ◽

Microwave Assisted ◽

On Line ◽

Molecularly Imprinted Monolith

Molecularly imprinted polymers (MIPs) possess target-customized and range-adjustable selectivity, and hence have been attracting increasing efforts to develop new synthetic methods and new forms of applications. By wisely choosing functional...

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Sensing Performance of Al and Sn Doped ZnO for Hydrogen Detection

Proceedings ◽

10.3390/proceedings2019014039 ◽

2019 ◽

Vol 14 (1) ◽

pp. 39

Author(s):

Zahira. El khalidi ◽

Maryam Siadat ◽

Elisabetta. Comini ◽

Salah. Fadili ◽

Philippe. Thevenin

Keyword(s):

Zinc Oxide ◽

Chemical Sensor ◽

Low Cost ◽

Zinc Powder ◽

Health Condition ◽

Vibration Modes ◽

X Ray Diffraction ◽

Grain Sizes ◽

Pure Oxide ◽

Doped Zno

Chemical gas sensors were studied long ago and nowadays, for the advantageous role they provide to the environment, health condition monitoring and protection. The recent studies focus on the semiconductors sensing abilities, especially of non toxic and low cost compounds. The present work describes the steps to elaborate and perform a chemical sensor using intrinsic and doped semiconductor zinc oxide. First, we synthesized pure oxide using zinc powder, then, two other samples were established where we introduced the same doping percentage of Al and Sn respectively. Using low cost spray pyrolysis, and respecting the same conditions of preparation. The obtained samples were then characterized by X Ray Diffraction (XRD) that revealed the hexagonal wurzite structure and higher crystallite density towards the direction (002), besides the appearance of the vibration modes related to zinc oxide, confirmed by Raman spectroscopy. SEM spectroscopy showed that the surface morphology is ideal for oxidizing/reduction reactions, due to the porous structure and the low grain sizes, especially observed for the sample Sn doped ZnO. The gas testing confirms these predictions showing that the highest response is related to Sn doped ZnO compared to ZnO and followed by Al doped ZnO. The films exhibited responses towards: CO, acetone, methanol, H2, ammonia and NO2. The concentrations were varied from 10 to 500 ppm and the working temperatures from 250 to 500°C, the optimal working temperatures were 350 and 400 °C. Sn doped ZnO showed a high response towards H2 gas target, with a sensitivity reaching 200 at 500 ppm, for 400 °C.

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