Cobalt Metal ion Doped Cerium Oxide (Co-CeO2) Nanoparticles Effect Enhanced Photocatalytic Activity

MRS Advances ◽  
2020 ◽  
pp. 1-13
Author(s):  
G. Killivalavan ◽  
B. Sathyaseelan ◽  
G. Kavitha ◽  
I. Baskarann ◽  
K. Senthilnathan ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Metal Ion ◽  
Chemical Properties ◽  
Visible Spectrum ◽  
Average Crystallite Size ◽  
Cobalt Metal ◽  
Uv Visible ◽  
Co Precipitation ◽  
Average Size ◽  
Physical And Chemical

Abstract The REE (rare-earth-elements) cerium (Ce) is the most abundant earth-crust element and their oxides have great attention in the form of nanocrystalline nature with superior physical and chemical properties. Pure and Co (1%, 3% and 5%) doped CeO2 nanoparticles (NPs) synthesized by co-precipitation technique were characterized through X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), UV-visible spectroscopy. XRD shows face-centred-cubic (FCC) crystal symmetry with average crystallite size 6–12 nm. HRTEM exhibits almost identical cubical shaped particles with average size 4–10 nm. Tuned band-gap may be observed from UV-visible spectrum of CeO2-NPs upon Co (1%, 3% & 5%) incorporation. Enhancement of the photocatalytic activity observed for Co-doped (1%, 3% & 5%) to the degradation of methylene-blue (MB) dye under visible-light absorption.

Fabrication and Radiation Dose Properties of Well-dispersed Calcium Borate Nanoparticles

2019 ◽  
Vol 9 (2) ◽  
pp. 198-209
Author(s):  
Maryam E. Haghiri ◽  
Nayereh Soltani ◽  
Elias Saion ◽  
Azra Izanloo ◽  
Ghazaleh Bahmanrokh ◽  
...  
Keyword(s):  
Polymer Concentration ◽  
Chemical Properties ◽  
Frequency Factor ◽  
Heating Process ◽  
Calcium Borate ◽  
Heating Treatment ◽  
Mean Size ◽  
Co Precipitation ◽  
Average Size ◽  
Physical And Chemical

Background:Development of novel materials represents a new and fast evolving application of research in physics and medicine. The area of nanomaterial research has presented interesting physical and chemical properties that cannot be obtained from their macroscopic counterparts.Objective:This study has attempted to attain well-dispersed nanoparticles by variation of polymer concentration.Methods:In order to obtain the calcium borate nanoparticles, polyvinyl pyrrolidone has been used as a capping agent and the preparation method was performed via simple co-precipitation technique followed by heating treatment. In absence of polymer, the heating process causes un-controlled growth of particles with more flocculation and the nanoplate-shaped particles with mean size of 16.0 ×30.0 nm was formed. The introduction of polymer concentration of 1 wt% was conducted to the formation of spherical shaped nanoparticles with sufficiently narrow size distribution and small average size of 5.5 nm and 13.0 nm for the initial precipitation and heating process, respectively. Moreover, the synthesized calcium borate nanoparticles showed good luminescence properties with a simple glow curve dominating at 150°C.Results:This curve was utilized to derive trapping parameters including the activation energy, order of kinetic and frequency factor.Conclusion:The well-dispersed calcium borate nanoparticles have been prepared successfully by introduction of sufficient concentration of polymer.

Removal of Mn(II) from Aqueous Solution Using Saponified Garlic Peel

2014 ◽  
Vol 694 ◽  
pp. 382-386 ◽  
Author(s):  
Bo Liang ◽  
Wan He Zhao ◽  
Kai Huang ◽  
Hong Min Zhu
Keyword(s):  
Metal Ion ◽  
Chemical Properties ◽  
Correlation Coefficients ◽  
Ion Concentration ◽  
Batch Adsorption ◽  
Maximum Adsorption Capacity ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Physical And Chemical ◽  
Garlic Peel

The removal of Mn (II) ion by saponified garlic peel (S-GP) was investigated using batch adsorption. SEM and FT-IR were employed to investigate the physical and chemical properties of S-GP. The adsorption was evaluated as a function of initial metal ion concentration, contact time and temperature. The maximum adsorption capacity for Mn (II) was 0.51 mol/kg, and the adsorption process followed the Langmuir model. Pseudo-second-order models fitted the experimental data well and kinetic parameters, rate constants, equilibrium sorption capacity and related correlation coefficients at various temperatures were calculated and discussed. A possible adsorption mechanism based on a cation exchange was proposed for the adsorption of Mn (II).

scholarly journals The effect of magnetite nanoparticles synthesis conditions on their ability to separate heavy metal ions

2017 ◽  
Vol 43 (2) ◽  
pp. 3-9 ◽  
Author(s):  
Magdalena Bobik ◽  
Irena Korus ◽  
Lidia Dudek
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Magnetite Nanoparticles ◽  
Metal Ion ◽  
Heavy Metal Ions ◽  
Average Crystallite Size ◽  
Iron Oxide Particles ◽  
Synthesis Conditions ◽  
Synthesis Parameters ◽  
Co Precipitation

Abstract Magnetite nanoparticles have become a promising material for scientific research. Among numerous technologies of their synthesis, co-precipitation seems to be the most convenient, less time-consuming and cheap method which produces fine and pure iron oxide particles applicable to environmental issues. The aim of the work was to investigate how the co-precipitation synthesis parameters, such as temperature and base volume, influence the magnetite nanoparticles ability to separate heavy metal ions. The synthesis were conducted at nine combinations of different ammonia volumes - 8 cm3, 10 cm3, 15 cm3 and temperatures - 30°C, 60°C, 90°C for each ammonia volume. Iron oxides synthesized at each combination were examined as an adsorbent of seven heavy metals: Cr(VI), Pb(II), Cr(III), Cu(II), Zn(II), Ni(II) and Cd(II). The representative sample of magnetite was characterized using XRD, SEM and BET methods. It was observed that more effective sorbent for majority of ions was produced at 30°C using 10 cm3 of ammonia. The characterization of the sample produced at these reaction conditions indicate that pure magnetite with an average crystallite size of 23.2 nm was obtained (XRD), the nanosized crystallites in the sample were agglomerated (SEM) and the specific surface area of the aggregates was estimated to be 55.64 m2·g-1 (BET). The general conclusion of the work is the evidence that magnetite nanoparticles have the ability to adsorb heavy metal ions from the aqueous solutions. The effectiveness of the process depends on many factors such as kind of heavy metal ion or the synthesis parameters of the sorbent.

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 Characterization and Photocatalytic Activity of Nano-TiO2 Doped with Iron and Niobium for Turquoise Blue Dye Removal

2012 ◽  
Vol 12 (1) ◽  
pp. 34 ◽  
Author(s):  
Nhat Minh Doan ◽  
Carl Renan Estrellan ◽  
Anton Purnomo ◽  
Susan Gallardo ◽  
Chris Salim ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Anatase Phase ◽  
Sol Gel ◽  
Chemical Properties ◽  
Band Gap Energy ◽  
Blue Dye ◽  
Nano Tio2 ◽  
Co Doping ◽  
Reaction Rate Constants ◽  
Physical And Chemical

The nano-TiO2 photocatalysts doped with Iron and Niobium for dye wastewater treatment were prepared by temperature-controlled sol-gel method. The effects of these dopants on the physical and chemical properties of TiO2 were compared with the commercially available Degussa TiO2 P25. Among these characteristics are crystalline size, the presence of absolute anatase phase, band gap energy and specific surface area. The characterization data were correlated to photocatalytic activities using Turquoise blue dye (TBD) as model pollutant. Single doping (with Nb) and co-doping (Fe and Nb) catalyst reached complete decolorization within 2.5 hours and 3 hours. In addition, their kinetic reaction rate constants of apparent first-order model are 0.0258 min-1 and 0.0225 min-1, respectively. The presence of Nb as traps is considered to play a crucial key in enhancing the photocatalytic activity.

scholarly journals From nanoscopic to macroscopic photo-driven motion in azobenzene-containing materials

Nanophotonics ◽  
2018 ◽  
Vol 7 (8) ◽  
pp. 1387-1422 ◽  
Author(s):  
Stefano L. Oscurato ◽  
Marcella Salvatore ◽  
Pasqualino Maddalena ◽  
Antonio Ambrosio
Keyword(s):  
Liquid Crystalline ◽  
Large Scale ◽  
Surface Engineering ◽  
Spatial Scales ◽  
Chemical Properties ◽  
Glassy Materials ◽  
Uv Visible ◽  
Physical And Chemical ◽  
And Robotics ◽  
And Chemical Properties

AbstractThe illumination of azobenzene molecules with UV/visible light efficiently converts the molecules between trans and cis isomerization states. Isomerization is accompanied by a large photo-induced molecular motion, which is able to significantly affect the physical and chemical properties of the materials in which they are incorporated. In some material systems, the nanoscopic structural movement of the isomerizing azobenzene molecules can be even propagated at macroscopic spatial scales. Reversible large-scale superficial photo-patterning and mechanical photo-actuation are efficiently achieved in azobenzene-containing glassy materials and liquid crystalline elastomers, respectively. This review covers several aspects related to the phenomenology and the applications of the light-driven macroscopic effects observed in these two classes of azomaterials, highlighting many of the possibilities they offer in different fields of science, like photonics, biology, surface engineering and robotics.

scholarly journals Green Synthesis of Mn + Cu Bimetallic Nanoparticles Using Vinca rosea Extract and Their Antioxidant, Antibacterial, and Catalytic Activities

Crystals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 72
Author(s):  
Mohamad M. Ahmad ◽  
Hicham Mahfoz Kotb ◽  
Shehla Mushtaq ◽  
Mir Waheed-Ur-Rehman ◽  
Christopher M. Maghanga ◽  
...  
Keyword(s):  
Bimetallic Nanoparticles ◽  
Dye Degradation ◽  
Antibacterial Properties ◽  
Chemical Properties ◽  
Inhibition Zone ◽  
Vinca Rosea ◽  
Ft Ir ◽  
Average Size ◽  
Phytochemical Components ◽  
Physical And Chemical

This article outlines the preparation of manganese-doped copper nanoparticles (Mn + Cu NPs) using Vinca rosea (L.) leaf extract as a convenient and environmentally friendly substance. UV–vis, FT–IR, XRD, SEM–EDAX, and DLS instrumental techniques were employed to describe the physical and chemical properties of synthesized V. rosea extract-mediated Vr-Mn + Cu NPs. The synthesized Vr-Mn + Cu NPs were observed to be monodispersed and spherical, with an average size of 412 nm. The plant extract includes a variety of phytochemical components. The Vr-Mn + Cu NPs also have potential antioxidant and antibacterial properties against selected pathogens. The green synthesized Vr-Mn + Cu NPs showed a maximum inhibition zone of 16.33 ± 0.57 mm against E. coli. For dye degradation, MR, EBT, and MO showed the highest degradation percentage capabilities with Vr-Mn + Cu NP-based adsorbents, which were determined to be 78.54 ± 0.16, 87.67 ± 0.06, and 69.79 ± 0.36. The results clearly show that biosynthesized Vr-Mn + Cu NPs may be employed as an antioxidant, antibacterial, photocatalytic dye degradation, and catalytic agent, as well as being ecologically benign.

scholarly journals Characterization of CdS Nanoparticles Synthesized Using Microwave-Assisted Polyol Method

2013 ◽  
Vol 667 ◽  
pp. 122-127 ◽  
Author(s):  
Nayereh Soltani ◽  
Elias Saion ◽  
Mohd Zobir Hussein ◽  
Robiah Bt. Yunus ◽  
Manizheh Navaseri
Keyword(s):  
Irradiation Time ◽  
Visible Spectrum ◽  
Blue Shift ◽  
Polyol Method ◽  
Molar Ratio ◽  
Cds Nanoparticles ◽  
Microwave Assisted ◽  
Uv Visible ◽  
Scherrer Formula ◽  
Average Size

Synthesis of cadmium sulfide (CdS) nanoparticles has been performed through the simple and rapid microwave-assisted polyol method, using cadmium chloride and thioacetamide as the cadmium and sulfur sources respectively. Attempts were made to control the size and crystallinity of the CdS nanoparticles by controlling microwave irradiation time and the initial molar ratio of the cadmium and sulfur sources. The structure of nanoparticles characterized by X-ray diffraction (XRD) was hexagonal. No peaks corresponding to impurities were detected, indicating the high purity of the product. The size of the prepared samples was calculated by Debye–Scherrer formula according to XRD spectra. The morphology of particles was observed in the transmission electron microscopy (TEM) images was spherical. The average size of nanoparticles was also estimated from these images. The optical absorption of CdS nanoparticles studied by UV-Visible spectroscopy showed a blue shift from bulk CdS due to quantum confinement. The size of nanoparticles was calculated by Brus formula according to UV-Visible spectrum and compared to XRD and TEM results.

scholarly journals Preparation and Physical and Photocatalytic Activity of a New Niobate Oxide Material Containing NbO4 Tetrahedra

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Hengkai Pan ◽  
Bei Wang ◽  
Feng Zhang ◽  
Weifeng Zhang ◽  
Guoqiang Li
Keyword(s):  
Photocatalytic Activity ◽  
Chemical Properties ◽  
Ambient Air ◽  
Oxygen Adsorption ◽  
Lattice Parameter ◽  
Oxide Material ◽  
Scattering Spectra ◽  
New Material ◽  
Raman Scattering Spectra ◽  
Physical And Chemical

The shape and connection type of MOx are critical to the physical and chemical properties. A series of new material Sr2-xNaxNbO4 containing NbO4 tetrahedra was prepared by controlling the ratio of SrCO3 to sodium niobate under ambient air. With increasing the content of Sr in the sample, the MOx shape will change from NbO6 octahedra to NbO4 tetrahedra, which is confirmed by the Raman scattering spectra. With increasing the content of NbO4 in the sample, the lattice parameter increases, optical band gap becomes larger, and the surface changes to be more active for oxygen adsorption, resulting in a higher photocatalytic activity.

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