scholarly journals Enhanced sunlight photocatalytic activity and biosafety of marine-driven synthesized cerium oxide nanoparticles

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Somayeh Safat ◽  
Foad Buazar ◽  
Salim Albukhaty ◽  
Soheila Matroodi
Keyword(s):  
Photocatalytic Activity ◽  
Band Gap ◽  
Color Change ◽  
Removal Rate ◽  
Average Crystallite Size ◽  
Face Centered Cubic ◽  
One Pot ◽  
Stabilizing Agents ◽  
Face Centered ◽  
Living Organisms

AbstractThis contribution presents the biosynthesis, physiochemical properties, toxicity and photocatalytic activity of biogenic CeO2 NPs using, for the first time, marine oyster extract as an effective and rich source of bioreducing and capping/stabilizing agents in a one-pot recipe. CeO2 NPs formation was initially confirmed through the color change from light green to pale yellow and subsequently, their corresponding absorption peak was spectroscopically determined at 310 nm with an optical band-gap of 4.67 eV using the DR-UV technique. Further, XRD and Raman analyses indicated that nanoceria possessed face-centered cubic arrangements without any impurities, having an average crystallite size of 10 nm. TEM and SEM results revealed that biogenic CeO2 NPs was approximately spherical in shape with a median particle size of 15 ± 1 nm. The presence of various bioorganic substances on the surface of nanoparticles was deduced by FTIR and TGA results. It is found that marine-based nanoceria shows no cytotoxic effect on the normal cell, thus indicating their enhanced biocompatibility and biosafety to living organisms. Environmentally, due to energy band gap, visible light-activated CeO2 nanocatalyst revealed superior photocatalytic performance on degradation of methylene blue pollutant with removal rate of 99%. Owing to the simplicity, cost-effectiveness, and environmentally friendly nature, this novel marine biosynthetic route paves the way for prospective applications of nanoparticles in various areas.

scholarly journals Enhanced Sunlight Photocatalytic Activity and Biosafety of Marine-Driven Synthesized Cerium Oxide Nanoparticles: A Future prospect

2021 ◽  
Author(s):  
Somayeh Safat ◽  
Foad Buazar ◽  
Soheila Matroodi ◽  
Salim Albukhaty
Keyword(s):  
Color Change ◽  
Average Crystallite Size ◽  
Face Centered Cubic ◽  
One Pot ◽  
Physiochemical Properties ◽  
Stabilizing Agents ◽  
Median Particle ◽  
Face Centered ◽  
Living Organisms ◽  
First Time

Abstract This contribution presents the biosynthesis, physiochemical properties, and biological activity of biogenic CeO2 NPs using, for the first time, marine oyster extract as an effective and rich source of bioreducing and capping/stabilizing agents in a one-pot recipe. CeO2 NPs formation was initially confirmed through the color change from light green to pale yellow and subsequently, their corresponding absorption peak was spectroscopically observed at 310 nm with an optical band-gap of 4.67 eV using the DR-UV technique. Further, XRD and Raman analyses indicated that nanoceria possessed face-centered cubic arrangements without any impurities, having an average crystallite size of 10 nm. TEM and histogram results revealed that biogenic CeO2 NPs was approximately spherical in shape with a median particle size of 15±1 nm. The presence of various bioorganic substances on the surface of nanoparticles was deduced by FTIR and TGA results. It is found that marine-based nanoceria shows no cytotoxic effect on the cell, thus indicating their enhanced biocompatibility and biosafety to living organisms. In contrast, nanoceria demonstrated as an effective bactericidal agent toward pathogens. Visible light-activated CeO2 nanocatalyst revealed rapid photodegradation of methylene blue. Owing to simplicity, cost-effectiveness, and environmentally friendly nature, this novel marine biosynthetic route paves the way for prospective applications of nanoparticles in various areas of bioscience.

scholarly journals Characterization of Cobalt Sulfide Thin Films Synthesized from Acidic Chemical Baths

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Tizazu Abza ◽  
Dereje Gelanu Dadi ◽  
Fekadu Gashaw Hone ◽  
Tesfaye Chebelew Meharu ◽  
Gebremeskel Tekle ◽  
...  
Keyword(s):  
Thin Films ◽  
Crystallite Size ◽  
Deposition Time ◽  
Average Crystallite Size ◽  
Cobalt Sulfide ◽  
Face Centered Cubic ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
Face Centered

Cobalt sulfide thin films were synthesized from acidic chemical baths by varying the deposition time. The powder X-ray diffraction studies indicated that there are hexagonal CoS, face-centered cubic Co3S4, and cubic Co9S8 phases of cobalt sulfide. The crystallite size of the hexagonal CoS phase decreased from 52.8 nm to 22.5 nm and that of the cubic Co9S8 phase increased from 11 nm to 60 nm as the deposition time increased from 2 hrs to 3.5 hrs. The scanning electron microscopic images revealed crack and pinhole free thin films with uniform and smooth background and few large polygonal grains on the surface. The band gap of the cobalt sulfide thin films decreased from 1.75 eV to 1.3 eV as the deposition time increased from 2 hrs to 3.5 hrs. The photoluminescence (PL) spectra of the films confirmed the emission of ultraviolet, violet, and blue lights. The intense PL emission of violet light at 384 nm had red shifted with increasing deposition time that could be resulted from the increase in the average crystallite size. The FTIR spectra of the films indicated the presence of OH, C-O-H, C-O, double sulfide, and Co-S groups. As the deposition time increased, the electrical resistivity of the cobalt sulfide thin films decreased due to the increase in both the crystallite size and the films’ thickness.

Photocatalytic Analysis and Characterization of Zn2SnO4 Nanoparticles Synthesized via Hydrothermal Method with Na2CO3 Mineralizer

2010 ◽  
Vol 97-101 ◽  
pp. 19-22 ◽  
Author(s):  
Yu Shiang Wu ◽  
Wen Ku Chang ◽  
Min Jou
Keyword(s):  
Photocatalytic Activity ◽  
Hydrothermal Process ◽  
Face Centered Cubic ◽  
X Ray Diffraction ◽  
Visible Absorption ◽  
Transmission Electron ◽  
Excellent Photocatalytic Activity ◽  
Face Centered ◽  
Xrd Patterns

Zinc stannate Zn2SnO4 (ZTO) nanoparticles were synthesized via a hydrothermal process utilizing sodium carbonate (Na2CO3) as a weak basic mineralizer. The samples were hydrothermally treated at 150, 200, and 250oC for 48 h. The X-ray diffraction (XRD) patterns show that the highly-crystalline ZTO nanostructure could be formed in a well-dispersed manner for the 250°C sample at a particle size of less than 50 nm. As determined from transmission electron microscopy (TEM) results, ZTO nanoparticles are face-centered cubic single crystals agglomerated together. The Raman spectra results showed that the ZTO nanocrystals have a spinel structure. Furthermore, photocatalytic activity was tested with methylene blue (MB) by UV irradiation. The ZTO synthesized by the 2 M Na2CO3 mineralizer at 250oC demonstrated excellent photocatalytic activity. The ZTO treated three different ways had three distinct UV-Visible absorption curves, which directly influences their corresponding photocatalytic activity.

CERIA NANOPARTICLES SYNTHESIZED BY A POLYMER PRECURSOR METHOD

2013 ◽  
Vol 22 ◽  
pp. 169-172
Author(s):  
B. SONI ◽  
S. BISWAS
Keyword(s):  
Sol Gel ◽  
Average Crystallite Size ◽  
Xrd Analysis ◽  
Poly Vinyl Alcohol ◽  
Face Centered Cubic ◽  
Ceria Nanoparticles ◽  
X Ray Diffraction ◽  
Precursor Method ◽  
Fluorite Type ◽  
Face Centered

We report a novel synthesis technique of ceria nanoparticles by a sol-gel type chemical process using poly-vinyl alcohol (PVA) as a capping as well as a reducing agent. The as-synthesized CeO 2 nanoparticles were characterized by X-ray diffraction (XRD) and Field Emission Scanning Electron Microscopy (FESEM). The XRD analysis reveals the fluorite type face centered cubic structure in the ceria nanoparticles with an average crystallite size of 6 nm and 9 nm for the samples calcined at 350°C and 400°C, respectively.

Photonic band gap in the face-centered cubic lattice of spherical shells connected by cylindrical tubes

2005 ◽  
Vol 72 (11) ◽  
Author(s):  
Hong-Bo Chen ◽  
Yong-Zheng Zhu ◽  
Yan-Ling Cao ◽  
Yan-Ping Wang ◽  
Yuan-Bin Chi
Keyword(s):  
Band Gap ◽  
Photonic Band Gap ◽  
Face Centered Cubic ◽  
Spherical Shells ◽  
Cubic Lattice ◽  
Cylindrical Tubes ◽  
The Face ◽  
Face Centered ◽  
Photonic Band

One Pot, Two Phases: Individual Orthorhombic and Face-Centered Cubic ZnSnO3 Obtained Synchronously in One Solution

2014 ◽  
Vol 53 (23) ◽  
pp. 12289-12296 ◽  
Author(s):  
Ying Wang ◽  
Peng Gao ◽  
Di Bao ◽  
Longqiang Wang ◽  
Yujin Chen ◽  
...  
Keyword(s):  
Face Centered Cubic ◽  
One Pot ◽  
Face Centered ◽  
Two Phases

scholarly journals Study on the Photonic Band Gaps of the Face Centered Cubic Crystals

2016 ◽  
Vol 70 ◽  
pp. 63-75
Author(s):  
K.B.S.K.B. Jayawardana ◽  
K.A.I.L. Wijewardena Gamalath
Keyword(s):  
Photonic Crystals ◽  
Band Gap ◽  
Filling Factor ◽  
Dielectric Material ◽  
Dielectric Materials ◽  
Face Centered Cubic ◽  
Gap Ratio ◽  
Dielectric Contrast ◽  
Dielectric Spheres ◽  
Face Centered

Since the dielectric contrast of photonic crystals play an important role in determining the existence of a photonic gap, the photonic energy bands, density of states of face centered cubic structured photonic crystals formed from spheres of several dielectric materials placed in air were calculated using the plane wave expansion method. A complete band gap was obtained between second and third bands with a gap to mid gap frequency ratio in the range for the dielectric contrast in the range 11-16 with dielectric spheres of radius with a filling factor of 0.134 and fordielectric contrast of 200 with . A complete gap was not found for the dielectric contrast of 3.9. A complete band gap can be obtained for filling factors for the dielectric contrast in the range with an optimum band gap for the filling factor 0.134 while GaAs () has almost a constant optimum band gap in this range. The largest gap to mid gap ratio of was obtained for GaP (). For dielectric spheres of and larger gap to mid gap ratio were obtained for the dielectric contrast while the largest were obtained for . The only dielectric material BaSrTiO3 () which gives a band gap for the filling factor of 0.4524 can be used in microwave applications.

Light-Mediated Green Synthesis of DNA-Capped Silver Nanoparticles and Their Antibacterial Activity

2020 ◽  
Vol 20 (3) ◽  
pp. 1678-1684
Author(s):  
Jiraporn Chumpol ◽  
Sineenat Siri
Keyword(s):  
Silver Nanoparticles ◽  
Green Synthesis ◽  
Light Exposure ◽  
Low Cost ◽  
Reaction Times ◽  
Antibacterial Activities ◽  
Face Centered Cubic ◽  
Stabilizing Agents ◽  
Face Centered ◽  
Average Size

Green synthesis offers an eco-friendly and low-cost approach for the synthesis of silver nanoparticles (AgNPs). Many studies have reported on the use of biomolecules, especially plant extracts, as reducing and/or stabilizing agents in place of toxic chemicals. This study reports on the use of bacterial genomic DNA as an alternative stabilizing agent for the green synthesis of AgNPs under light activation. With both increased DNA quantities and reaction times under light exposure, more stabilized AgNPs formed as indicated by the surface plasmon resonance intensities. The synthesized AgNPs were spherical with an average size of 61.36±10.15 nm as calculated using the dynamic light scattering (DLS) technique. The X-ray diffraction, selected area electron diffraction, and high resolution transmission electron microscope (TEM) analyses confirmed the formation of face-centered cubic (fcc) structured AgNPs. The produced AgNPs exhibited antibacterial activities against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, suggesting its potential application as an antibacterial agent.

Synthesis of NiCu Alloy Nanoparticles by Arc Plasma Evaporation

2013 ◽  
Vol 710 ◽  
pp. 157-160
Author(s):  
Li Xin Li ◽  
Zhong Juan Yang ◽  
Ming Li
Keyword(s):  
Room Temperature ◽  
Raw Materials ◽  
Average Crystallite Size ◽  
Alloy Nanoparticles ◽  
Face Centered Cubic ◽  
Arc Plasma ◽  
Transmission Electron ◽  
Face Centered ◽  
Bulk Alloys ◽  
Microscopy Images

The NiCu nanoparticles were synthesized from NixCu1-x (20 at. % < x < 80 at. %) bulk alloys with arc plasma technique. The experimental results indicated that the crystal structure of the powders is face centered cubic structure, the same as the bulk raw materials. The composition between the prepared powders and the bulk alloys altered with the content of the nickel and copper. With Scherrer equation, the average crystallite size was determined to be 50 nm, which is consistent with the results achieved from the TEM (transmission electron microscopy) images. Also the TEM images showed that some of the nanoparticles could aggregate and grew into micro-size particles at room temperature. The largest size of the grown particle at room temperature was about 1 μm.

Exploring Space Groups for Three Dimensional Photonic Band Gap Structures Via Level Set Equations: The Face Centered Cubic Lattice

2003 ◽  
Vol 788 ◽  
Author(s):  
Martin Maldovan ◽  
Chaitanya K. Ullal ◽  
Craig W. Carter ◽  
Edwin L. Thomas
Keyword(s):  
Band Gap ◽  
Level Set ◽  
Photonic Band Gap ◽  
Band Gaps ◽  
High Symmetry ◽  
Face Centered Cubic ◽  
Photonic Band Gaps ◽  
Basic Set ◽  
Face Centered ◽  
Photonic Band

ABSTRACTA level set approach was used to study photonic band gaps for dielectric composites with symmetries of the eleven face centered cubic lattices. Candidate structures were modeled for each group by a 3D surface given by f(x,y,z)-t=0 obtained by equating f to an appropriate sum of structure factor terms. This approach allows us to easily map different structures and gives us an insight into the effects of symmetry, connectivity and genus on photonic band gaps. It is seen that a basic set of symmetries defines the essential band gap and connectivity. The remaining symmetry elements modify the band gap. The eleven lattices are classified into four fundamental topologies on the basis of the occupancy of high symmetry Wyckoff sites. Of the fundamental topologies studied, three display band gaps--- including two: the (F-RD) and a group 216 structure that have not been reported previously.

Sign in / Sign up

Export Citation Format

Share Document