scholarly journals Study on quenching effect of nitrite ions on zinc oxide modified by polyvinylpyrrolidone

2015 ◽  
Vol 11 (3) ◽  
Author(s):  
Ing Hua Tang ◽  
Siti Zarina Mohd So’ad ◽  
Hendrik O. Lintang ◽  
Leny Yuliati
Keyword(s):  
Zinc Oxide ◽  
Chemical Properties ◽  
Precipitation Method ◽  
Broad Absorption Band ◽  
Quenching Effect ◽  
Physical Mixing ◽  
Mixing Method ◽  
Volmer Plot ◽  
Co Precipitation ◽  
Physical And Chemical

Zinc oxide (ZnO) is appeared to be an attractive material for application for multidisciplinary fields, owing to its unique physical and chemical properties. In this study, ZnO was synthesized using the co-precipitation method, where the zinc acetate was used as the precursor. The ZnO was further modified by adding different amounts of polyvinylpyrrolidone (PVP) via simple physical mixing method to obtain PVP/ZnO composites. The ZnO and the PVP/ZnO composites were characterized using Fourier transform infrared (FTIR), diffuse reflectance ultraviolet-visible (DR UV-Vis), and fluorescence spectroscopy. The FTIR spectra detected the presence of ZnO group and the functional groups from the PVP. The PVP peaks become more apparent with the increase of the PVP amount. From the DR UV-Vis spectra, no significant change was observed after modification with the PVP, and all composites showed similar broad absorption band to that of the ZnO. The fluorescence spectra showed that the addition of PVP decreased the emission intensity and red shifted the peak wavelength, indicating certain interactions between the ZnO and the added PVP. Quenching study was investigated in the presence of nitrite ions (NO2-) with various concentrations (2-10 mM). A linear Stern-Volmer plot was observed and the highest quenching constant rate (KSV) was obtained on the PVP/ZnO sample with PVP content of 0.1 wt%. This study demonstrated that the addition of the PVP on the ZnO improved the interaction between the ZnO and the NO2-, which will be one of the important factors for sensing and catalytic applications for detection and conversion of NO2-.

scholarly journals Preparation of highly active zinc oxide for photocatalytic removal of phenol: Direct calcination versus co-precipitation method

2015 ◽  
Vol 11 (3) ◽  
Author(s):  
Faisal Hussin ◽  
Hendrik O. Lintang ◽  
Lee Siew Ling ◽  
Leny Yuliati
Keyword(s):  
Zinc Oxide ◽  
Uv Light ◽  
Light Irradiation ◽  
Precipitation Method ◽  
Highly Active ◽  
Uv Light Irradiation ◽  
Photocatalytic Removal ◽  
Volmer Plot ◽  
Xrd Patterns ◽  
Co Precipitation

Photocatalytic removal of phenol under UV light irradiation was studied on zinc oxide (ZnO) photocatalysts, which were prepared via direct calcination (DC), and co-precipitation (CP) methods. The XRD patterns revealed that all of the prepared ZnO samples showed wurtzite structure, in which the ZnO-CP showed higher intensity of the diffraction peaks than the ZnO-DC sample. Optical and fluorescence properties of the prepared ZnO samples were similar to each other as confirmed by DR UV-Vis and fluorescence spectroscopy, respectively. The Stern-Volmer plot was investigated to study the interactions between the emission sites and the phenol. It was obtained that the emission sites of the ZnO-CP gave better interactions towards phenol molecules as compared to the ZnO-DC. After 6 hours reaction under UV light irradiation, the ZnO-CP sample showed two times higher photocatalytic activity for removal of phenol (10%) than that of the ZnO-DC (5%). It was suggested that the high activity observed on the ZnO-CP sample would be due to high crystallinity and good interactions with phenol. These results clearly suggested that the co-precipitation method was a good approach to prepare the highly active ZnO for the photocatalytic removal of phenol.

Synthesis of Fe3O4 Magnetic Nanoparticles in a Helical Microreactor

2020 ◽  
Vol 842 ◽  
pp. 174-181
Author(s):  
Dan Wang ◽  
Mudassir Iqbal ◽  
Ming Qiao Zhu
Keyword(s):  
Magnetic Nanoparticles ◽  
Saturation Magnetization ◽  
Chemical Properties ◽  
Precipitation Method ◽  
Physical And Chemical Properties ◽  
Reaction Conditions ◽  
Ft Ir ◽  
Co Precipitation ◽  
Physical And Chemical ◽  
And Chemical Properties

Fe3O4 nanoparticles (NPs) have previously been employed in various fields owing to their unique physical and chemical properties. In this paper, Fe3O4 NPs are prepared by co-precipitation method in a helical microreactor under different reaction conditions which affect the size of Fe3O4 NPs. The product is characterized by FT-IR and XPS. Also, VSM characterization shows that Fe3O4 exhibits typical superparamagnetic behavior and the saturation magnetization of NPs is 53 emu/g.

scholarly journals The improved photostability of naproxen in the inclusion complex with 2-hydroxypropyl-β-cyclodextrin

2015 ◽  
Vol 69 (4) ◽  
pp. 361-370 ◽  
Author(s):  
Snezana Ilic-Stojanovic ◽  
Vesna Nikolic ◽  
Ljubisa Nikolic ◽  
Aleksandar Zdravkovic ◽  
Agnes Kapor ◽  
...  
Keyword(s):  
Inclusion Complex ◽  
Chemical Properties ◽  
Precipitation Method ◽  
Molar Ratio ◽  
Physical And Chemical Properties ◽  
Ftir Analysis ◽  
Molecular Inclusion ◽  
Co Precipitation ◽  
Physical And Chemical ◽  
And Chemical Properties

The aim of this work was the preparation of the inclusion complex of naproxen with 2-hydroxypropyl-?-cyclodextrin (HP-?-CD) in order to improve the physical and chemical properties of naproxen. The molecular inclusion complexes of naproxen with HP-?-CD were prepared by using the co-precipitation method in the solid state with the molar ratio of 1:1. The structure of the obtained complex was characterized by using FTIR, 1H NMR, UV-Vis and XRD methods. The testing of naproxen photostability by the UV-Vis method indicated the degradation to aromatic ketone, 2-acetyl-6-methoxynaphthalene. FTIR analysis showed that the degradation started 15 days after the exposure of naproxen to daylight while the inclusion complex of naproxen: 2-hydroxypropyl-?-cyclodextrin was photostable for a period of 30 days.

Thermodynamic and anticancer properties of inorganic zinc oxide nanoparticles synthesized through co-precipitation method

2021 ◽  
Vol 330 ◽  
pp. 115602
Author(s):  
Seyyed Vahid Mousazad Goorabjavari ◽  
Fateme Golmohamadi ◽  
Saba Haririmonfared ◽  
Hosein Ahmadi ◽  
Soheil Golisani ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Zinc Oxide Nanoparticles ◽  
Precipitation Method ◽  
Oxide Nanoparticles ◽  
Anticancer Properties ◽  
Co Precipitation

Synthesis of Zn1−xCdxO Nanoparticles by Co-Precipitation: Structural, Optical and Photodetection Analysis

2017 ◽  
Vol 17 (01n02) ◽  
pp. 1760015 ◽  
Author(s):  
Anju Anna Jacob ◽  
L. Balakrishnan ◽  
S. R. Meher ◽  
K. Shambavi ◽  
Z. C. Alex
Keyword(s):  
Zinc Oxide ◽  
Energy Dispersive Spectrometer ◽  
Ultra Violet ◽  
Wide Bandgap ◽  
Precipitation Method ◽  
Cutoff Wavelength ◽  
X Ray ◽  
Wide Bandgap Semiconductor ◽  
Co Precipitation ◽  
Scanning Electron

Zinc oxide (ZnO) is a wide bandgap semiconductor with excellent photoresponse in ultra-violet (UV) regime. Tuning the bandgap of ZnO by alloying with cadmium can shift its absorption cutoff wavelength from UV to visible (Vis) region. Our work aims at synthesis of Zn[Formula: see text]CdxO nanoparticles by co-precipitation method for the fabrication of photodetector. The properties of nanoparticles were analyzed using X-ray diffractometer, UV–Vis spectrometer, scanning electron microscope and energy dispersive spectrometer. The incorporation of cadmium without altering the wurtzite structure resulted in the red shift in the absorption edge of ZnO. Further, the photoresponse characteristics of Zn[Formula: see text]CdxO nanopowders were investigated by fabricating photodetectors. It has been found that with Cd alloying the photosensitivity was increased in the UVA-violet as well in the blue region.

scholarly journals The Influence of the Preparation Method on the Physico-Chemical Properties and Catalytic Activities of Ce-Modified LDH Structures Used as Catalysts in Condensation Reactions

Molecules ◽  
2021 ◽  
Vol 26 (20) ◽  
pp. 6191
Author(s):  
Alexandra-Elisabeta Stamate ◽  
Rodica Zăvoianu ◽  
Octavian Dumitru Pavel ◽  
Ruxandra Birjega ◽  
Andreea Matei ◽  
...  
Keyword(s):  
Preparation Method ◽  
Mixed Oxides ◽  
Condensation Reaction ◽  
Chemical Properties ◽  
Precipitation Method ◽  
Synthesis Methods ◽  
Molar Ratios ◽  
Base Catalysts ◽  
Physico Chemical ◽  
Co Precipitation

Mechanical activation and mechanochemical reactions are the subjects of mechanochemistry, a special branch of chemistry studied intensively since the 19th century. Herein, we comparably describe two synthesis methods used to obtain the following layered double hydroxide doped with cerium, Mg3Al0.75Ce0.25(OH)8(CO3)0.5·2H2O: the mechanochemical route and the co-precipitation method, respectively. The influence of the preparation method on the physico-chemical properties as determined by multiple techniques such as XRD, SEM, EDS, XPS, DRIFT, RAMAN, DR-UV-VIS, basicity, acidity, real/bulk densities, and BET measurements was also analyzed. The obtained samples, abbreviated HTCe-PP (prepared by co-precipitation) and HTCe-MC (prepared by mechanochemical method), and their corresponding mixed oxides, Ce-PP (resulting from HTCe-PP) and Ce-MC (resulting from HTCe-MC), were used as base catalysts in the self-condensation reaction of cyclohexanone and two Claisen–Schmidt condensations, which involve the reaction between an aromatic aldehyde and a ketone, at different molar ratios to synthesize compounds with significant biologic activity from the flavonoid family, namely chalcone (1,3-diphenyl-2-propen-1-one) and flavone (2-phenyl-4H-1benzoxiran-4-one). The mechanochemical route was shown to have indisputable advantages over the co-precipitation method for both the catalytic activity of the solids and the costs.

scholarly journals Metal Based-oxide Nanoparticles Assisted the Uptake of the Essential Elements and Phytoremediation of Populus Alba : Essential Metabolic Processes and Genetic Stability

2021 ◽  
Author(s):  
Mohamed F. Ahmed ◽  
Mostafa A. Ibrahim ◽  
Ahmed S. Mansour ◽  
Ahmed N. Emam ◽  
Ashraf B. Abd El-Razik ◽  
...  
Keyword(s):  
Metal Oxides ◽  
Chemical Properties ◽  
Essential Elements ◽  
Precipitation Method ◽  
Populus Alba ◽  
Root Number ◽  
Zno Nps ◽  
Significant Difference ◽  
Co Precipitation ◽  
And Control

Abstract The present study evaluated the phytoremediation activities of Populus alba upon using nano metal-based-oxides (i.e., Fe2O3, ZnO, and Mn2O3-NPs) as analogues of three main heavy metals Fe, Zn and Mn exist in soil as micronutrients at three different concentrations (i.e., 20, 40, and 60 mg/L) compared to the control. The as-prepared nanoparticles have been prepared via co-precipitation method. In addition, the physico-chemical properties were investigated using transmission electron microscopy, Fourier transform infrared spectra, X-ray diffraction and dynamic light scattering techniques. Overall, a significant difference in the biomass production-related parameters such as fresh weight, shoot length, root length, and root number compared to control upon the treatment with micronutrients-based nano-metal-oxides (i.e., Mn2O3 > Fe2O3 > ZnO NPs, respectively), except a significant increase in the root number of Populus alba plant upon their treatment with ZnO NPs compared to other prepared nano-metal-oxides and control. Also, a remarkable increase in the chlorophyll index was monitored upon treatment with Fe2O3 than other used Mn2O3 and ZnO NPs, respectively. Moreover, RAPD-PCR bioassays were applied and the actual 6 primers showed a genetic variation percentage of 34.17% indicating that Populus alba is highly genetically stable even in a highly contaminated environment/soil. All these data enhance the idea of using the Populus alba plant in phytoremediation and heavy metal uptake as micronutrients to clean up the surroundings.

Impact of Synthesis Methods on Structural and Antifungal Properties of Metal Sulfide Nanoparticles

2021 ◽  
Vol 21 (12) ◽  
pp. 5896-5905
Author(s):  
Radha Ahuja ◽  
Anjali Sidhu ◽  
Anju Bala
Keyword(s):  
Electron Microscope ◽  
Chemical Properties ◽  
Metal Sulfide ◽  
Phytopathogenic Fungi ◽  
Biologically Active ◽  
Precipitation Method ◽  
Synthesis Methods ◽  
Sonochemical Method ◽  
Antifungal Properties ◽  
Co Precipitation

Nanotechnology has the ability to produce novel nano-sized materials with excellent physical and chemical properties to act against phytopathogenic diseases, essential for revolution of agriculture and food industry. The development of facile, reliable and eco-friendly processes for the synthesis of biologically active nanomaterials is an important aspect of nanotechnology. In the present paper, we attempted to compare sonochemical and co-precipitation method for the synthesis of metal sulfide nanoparticles (MS-NPs) for their structural and antifungal properties against various phytopathogenic fungi of rice. The preparation of nanospheres (NSs) and nano rods (NRs) of CuS, FeS and MnS was monitored by UV-Visible spectroscopy complemented by transmission electron microscope (TEM), scanning electron microscope (SEM), atomic force microscopy (AFM), dynamic light scattering (DLS) and Zeta potential analyser. Sonochemical method resulted in formation of spherical shaped nanoparticles of size (7–120 nm), smaller than those of nanorods (50–200 nm) prepared by co-precipitation produced. It was observed that the metal sulfide nanospheres exhibited a better antifungal potential against D. oryzae, C. lunata and S. oryzae as compared to rod shaped metal sulfide nanoparticles. Smaller size and large surface area of spherical shaped particles opens up an important perspective of the prepared MS-NPs.

Structural and Dielectric Properties of Zn1-xMoxO Nanoparticles

2020 ◽  
Vol 13 (2) ◽  
pp. 165-170
Keyword(s):  
Zinc Oxide ◽  
Dielectric Properties ◽  
Ac Conductivity ◽  
Hexagonal Wurtzite Structure ◽  
Dielectric Constants ◽  
Precipitation Method ◽  
Dielectric Parameters ◽  
Mo Doping ◽  
Lcr Meter ◽  
Co Precipitation

Abstract: In this work, samples of zinc oxide nanoparticles doped by molybdenum (Zn1-xMoxO with 0 ≤ x ≤ 0.1) were prepared by using the wet co-precipitation method. The characterization of the prepared samples was carried out by means of X-ray powder diffraction (XRD). The samples reserved their hexagonal wurtzite structure with Mo doping and showed a decrease in the crystallite size up to x = 0.04 followed by a further increase. On the other hand, dielectric measurements were performed using an LCR meter. The effect of frequency and temperature on the dielectric properties such as the real and imaginary parts of dielectric constant (ε^' and ε'', respectively), dielectric loss (tanδ) and ac-conductivity (σ_ac) of Mo-doped zinc oxide samples, was studied in the frequency range (100 Hz - 1 MHz) and at temperatures (300 - 773 K). The values of room temperature dielectric parameters were found to be strongly dependent on the Mo-doping. However, the increase in temperature caused an enhancement in the values of the dielectric parameters, particularly at 773 K. Keywords: Zinc oxide, XRD, Dielectric constants, Ac-conductivity.

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