Silver Nanoparticle-Based Sensor for the Selective Detection of Nickel Ions

Silver nanoparticles (AgNPs) can be used as a surface plasmon resonance (SPR) colorimetric sensor; the correlation between the SPR phenomenon and the aggregation state of nanoparticle allows the real-time detection of a target molecule. Surface functionalization of NPs with proper molecular baits is often performed to establish the selectivity of the sensor. This work reports on the synthesis of AgNPs under reducing conditions and on the functionalization thereof with mercaptoundecanoic acid (11-MUA). UV-VIS Spectroscopy confirmed the formation of AgNPs, eliciting a surface plasmon absorption band (SPAB) at 393 nm that shifted to 417 nm upon surface coating. Dynamic light scattering was used to investigate the surface coatings; moreover, pelleted AgNPs@11MUA nanoparticles were characterized by scanning electron microscopy (SEM), energy dispersive X-ray analyzers (EDX), and infrared spectroscopy to corroborate the presence of 11MUA on the surface. Most interestingly, the resulting AgNPs@11MUA selectively detected micromolar levels of Ni2+, also in the presence of other cations such as Mn2+, Co2+, Cd2+, Cu2+, Zn2+, Fe2+, Hg2+, Pb2+, and Cr3+.

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Zn(II) Complex for Highly Sensitive and Selective Detection of Acetone at Room Temperature

10.20944/preprints201912.0050.v1 ◽

2019 ◽

Author(s):

Mohd. Muddassir ◽

Abdullah Alarifi ◽

Mohammad Usman

Keyword(s):

Room Temperature ◽

High Selectivity ◽

Resonance Spectroscopy ◽

Monoclinic Space Group ◽

Selective Detection ◽

X Ray ◽

X Ray Crystallography ◽

Highly Sensitive ◽

Vis Spectroscopy ◽

Perchlorate Complex

A Zn(II) perchlorate complex has been prepared and characterized by single X-ray crystallography, nuclear magnetic resonance spectroscopy, thermogravimetric analysis, infrared spectroscopy, elemental analysis, and UV-vis spectroscopy. The complex crystallizes in the monoclinic space group P21/c (Z = 4) with a pentacoordinated zinc center. Interestingly, the Zn complex was found be to a potential fluorophore that could sense acetone and other ketones with high selectivity and sensitivity.

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The adsorption and dispersing mechanisms of sodium lignosulfonate on Al2O3 particles in aqueous solution

Holzforschung ◽

10.1515/hf-2012-0108 ◽

2013 ◽

Vol 67 (4) ◽

pp. 387-394 ◽

Cited By ~ 18

Author(s):

Rong Li ◽

Dongjie Yang ◽

Wenyuan Guo ◽

Xueqing Qiu

Keyword(s):

Metal Cation ◽

Photoelectron Spectroscopy ◽

Low Ph ◽

Repulsive Force ◽

Sodium Lignosulfonate ◽

Aggregation State ◽

Potential Measurement ◽

X Ray ◽

Ph Values ◽

Vis Spectroscopy

Abstract The adsorption behavior and dispersion efficiency of sodium lignosulfonate (NaLS) on Al2O3 particles at different pH values were investigated by UV-Vis spectroscopy, zeta potential measurement, X-ray photoelectron spectroscopy, and viscosity measurements. The effects of the additives urea, Na2SO4, and NaCl were tested. At low pH values, NaLS adsorbed on the Al2O3 particles in the form of aggregates and at high pH values as separated single molecules. At pH 3–11, the adsorption was not affected through addition of urea, ruling out hydrogen bond as a controlling factor. By adding Na2SO4 and NaCl, the main driving force was the synergistic effect of the electrostatic interaction and the metal cation-π interaction at pH<pHIEP (IEP, isoelectric point), whereas the metal cation-π interaction was dominant at pH>pHIEP. The dispersing mechanism was mainly attributed to the steric hindrance (at pH<pHIEP) and the electrostatic repulsive force (at pH>pHIEP) owing to the differences in the aggregation state of the adsorbed molecules.

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Exploring the characteristics of the nickel oxide nanoparticles via Sol - gel method

Nanoscale Reports ◽

10.26524/nr.3.24 ◽

2020 ◽

Vol 3 (3) ◽

Author(s):

Jothi M ◽

Sowmiya K

Keyword(s):

Nickel Oxide ◽

Ph Value ◽

Lattice Structure ◽

Sol Gel ◽

Systematic Change ◽

Average Crystalline Size ◽

Nio Nanoparticles ◽

Nickel Oxide Nanoparticles ◽

X Ray ◽

Vis Spectroscopy

Nickel Oxide (NiO) is an important transition metal oxide with cubic lattice structure. NiO is thermally stable that is suitable for tremendous applications in the field of optic, ceramic,glass, electro-chromic coatings, plastics, textiles, nanowires, nanofibers, electronics,energy technology, bio-medicine, magnetism and so on. In this present study, NiO nanoparticles were successfully synthesized by sol-gel technique. Nano-sols were prepared by dissolving Nickel-Chloride [NiCl2.6H2O] in NaOH solvent and were converted into nano structured gel on precipitation. A systematic change in preparation parameters like calcination temperature, time, pH value has been noticed in order to predict the influence on crystallite size. Then the prepared samples were characterized by the X-ray Diffraction Spectroscopic (XRD), UV-VIS Spectroscopy, Fourier Transform Infra-Red Spectroscopy (FTIR), Energy Dispersive X-ray Spectroscopy (EDX), Scanning Electron Microscopy (SEM) and Particle Size Analyzer (PSA). From XRD, the average crystalline-size has been calculated by Debye-Scherrer Equation and it was found to be 12.17 nm and the band gap energy of Nickel oxide (NiO) from UV studies reveals around 3.85 eV. Further, EDX and FTIR studies, confirm the presences of NiO nanoparticles. The SEM study exhibits the spherical like morphology of Nickel oxide (NiO). Further from PSA, the mean value of NiO nanoparticles has been determined.

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Nanocomposite synthesis by thermolysis of [Ag(hfac)(COD)] in amorphous polystyrene

Science and Engineering of Composite Materials ◽

10.1515/secm-2011-0125 ◽

2012 ◽

Vol 19 (2) ◽

pp. 195-197 ◽

Cited By ~ 4

Author(s):

Gianfranco Carotenuto ◽

Mariano Palomba ◽

Luigi Nicolais

Keyword(s):

Polymer Matrix ◽

Nanocomposite Films ◽

Numerical Density ◽

Silver Particles ◽

X Ray ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Yellow Coloration ◽

Color Filters ◽

Silver Atoms

AbstractLightfast color filters (intensively and brightly colored) can be easily produced by dying optical plastics with the surface plasmon resonance (SPR) of metal nanoparticles such as silver and gold. Here, color filters based on silver nanoparticles embedded in amorphous polystyrene have been prepared by dissolving and thermally decomposing (1,5-cyclooctadiene)(hexafluoro-acetylacetonate)silver(I) in amorphous polystyrene. The metal precursor quickly decomposes (10 s, at 180°C), leading to silver atoms that clusterize and produce a non-aggregated dispersion of silver particles in the polymer matrix. The intensity of the yellow coloration due to the SPR of nanoscopic silver can be widely tuned simply by varying the cluster numerical density in the polymer matrix that depends on the silver precursor concentration. The obtained nanocomposite films have been characterized by X-ray power diffraction, transmission electron microscopy, and UV-Vis spectroscopy.

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Green synthesized Ag-TiO2 for degradation of organic dye through visible light driven photo-reactor and its kinetics

International Journal of Chemical Reactor Engineering ◽

10.1515/ijcre-2021-0111 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Titikshya Mohapatra ◽

Sakshi Manekar ◽

Vijyendra Kumar Sahu ◽

Ashwini Kumar Soni ◽

Sudip Banerjee ◽

...

Keyword(s):

Visible Light ◽

Mangifera Indica ◽

Band Gap Energy ◽

Photo Degradation ◽

X Ray ◽

Green Approach ◽

Vis Spectroscopy ◽

Rate Of Reaction ◽

Visible Light Driven ◽

Modification Of Titanium

Abstract This study reports a green approach for the modification of titanium dioxide (TiO2) nanoparticles with immobilization of silver nanoparticles. One of the natural sources i.e., Mangifera indica leaf extract was utilized as reducing and capping agent for the fabrication of Ag-TiO2 nanocatalyst. Further, the surface morphology and band-gap energy of prepared Ag-TiO2 were analyzed by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and UV–Vis spectroscopy. Also, it was characterized by X-ray Powder Diffraction (XRD) which provides the information regarding the crystallinity of the Ag-TiO2. Subsequently, photo activity of Ag-TiO2 was investigated for the degradation of methylene blue (MB) dye wastewater through visible light driven photoreactor. The Ag-TiO2 provided highest (68%) of photo-degradation efficiency within 110 min for 7.81 × 10−5 mol/L initial MB concentration at pH 8 by using 0.19 g/L photocatalyst. Further, addition of 10 mM H2O2 boost up the MB photodegradation to 74%. The kinetic study confirmed the MB degradation followed first order rate of reaction.

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Photocatalytic activity of Pr-modified TiO2 for the degradation of bisphenol A

SN Applied Sciences ◽

10.1007/s42452-021-04284-2 ◽

2021 ◽

Vol 3 (2) ◽

Author(s):

Denise S. Cordeiro ◽

Fernando L. Cassio ◽

Larissa Ciccotti ◽

Thiago L. R. Hewer ◽

Paola Corio ◽

...

Keyword(s):

Photocatalytic Activity ◽

Bisphenol A ◽

Pore Diameter ◽

Sol Gel ◽

Bandgap Energy ◽

Photocatalytic Efficiency ◽

Average Pore ◽

X Ray ◽

Vis Spectroscopy ◽

Adsorption Desorption

AbstractPraseodymium doped TiO2 nanoparticles were successfully prepared by the sol–gel method and characterized by X-ray powder diffraction, N2 adsorption–desorption isotherm, and UV–vis spectroscopy. The effects of the dopant on the crystallite size, specific surface area, average pore diameter, pore volume, and bandgap energy were investigated. The photocatalytic activity of the catalysts was evaluated by bisphenol A degradation and mineralization, which is a representative endocrine disruptor. Furthermore, under visible light irradiation the Pr-modified TiO2 photocatalysts exhibited higher photocatalytic efficiency than unmodified TiO2. When praseodymium was loaded (1.0–5.0%) onto the surface of TiO2, the rates of degradation and mineralization were increased 3–5 times.

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Synthesis and characterization of Fe, Co, and Ni colloids in 2-mercaptoethanol

Nanomaterials and Nanotechnology ◽

10.1177/1847980420966883 ◽

2020 ◽

Vol 10 ◽

pp. 184798042096688

Author(s):

Galo Cárdenas-Triviño ◽

Sergio Triviño-Matus

Keyword(s):

Electron Microscopy ◽

Electron Diffraction ◽

Colloidal Dispersions ◽

Synthesis And Characterization ◽

X Ray ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Chemical Liquid Deposition ◽

Liquid Deposition

Metal colloids in 2-mercaptoethanol using nanoparticles (NPs) of iron (Fe), cobalt (Co), and nickel (Ni) were prepared by chemical liquid deposition method. Transmission electron microscopy, electron diffraction, UV-VIS spectroscopy, and scanning electron microscopy with electron dispersive X-ray spectroscopy characterized the resulting colloidal dispersions. The NPs exhibited sizes with ranges from 9.8 nm for Fe, 3.7 nm for Co, and 7.2 nm for Ni. The electron diffraction shows the presence of the metals in its elemental state Fe (0), Co (0), and Ni (0) and also some compounds FeO (OH), CoCo2S4, and NiNi2S4.

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Vacuum-Free and Highly Dense Nanoparticle Based Low-Band-Gap CuInSe2 Thin-Films Manufactured by Face-to-Face Annealing with Application of Uniaxial Mechanical Pressure

Coatings ◽

10.3390/coatings9080484 ◽

2019 ◽

Vol 9 (8) ◽

pp. 484

Author(s):

Matthias Schuster ◽

Dominik Stapf ◽

Tobias Osterrieder ◽

Vincent Barthel ◽

Peter J. Wellmann

Keyword(s):

Thin Films ◽

Band Gap ◽

Coarse Grained ◽

High Porosity ◽

Low Band Gap ◽

Seeding Layer ◽

X Ray ◽

Face To Face ◽

Copper Indium ◽

Vis Spectroscopy

Copper indium gallium sulfo-selenide (CIGS) based solar cells show the highest conversion efficiencies among all thin-film photovoltaic competition. However, the absorber material manufacturing is in most cases dependent on vacuum-technology like sputtering and evaporation, and the use of toxic and environmentally harmful substances like H2Se. In this work, the goal to fabricate dense, coarse grained CuInSe2 (CISe) thin-films with vacuum-free processing based on nanoparticle (NP) precursors was achieved. Bimetallic copper-indium, elemental selenium and binary selenide (Cu2−xSe and In2Se3) NPs were synthesized by wet-chemical methods and dispersed in nontoxic solvents. Layer-stacks from these inks were printed on molybdenum coated float-glass-substrates via doctor-blading. During the temperature treatment, a face-to-face technique and mechanically applied pressure were used to transform the precursor-stacks into dense CuInSe2 films. By combining liquid phase sintering and pressure sintering, and using a seeding layer later on, issues like high porosity, oxidation, or selenium- and indium-depletion were overcome. There was no need for external Se atmosphere or H2Se gas, as all of the Se was directly in the precursor and could not leave the face-to-face sandwich. All thin-films were characterized with scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and UV/vis spectroscopy. Dense CISe layers with a thickness of about 2–3 µm and low band gap energies of 0.93–0.97 eV were formed in this work, which show potential to be used as a solar cell absorber.

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On the selective aerobic oxidation of benzyl alcohol with Pd/Au-nanoparticles in batch and flow

Nanotechnology Reviews ◽

10.1515/ntrev-2012-0085 ◽

2014 ◽

Vol 3 (1) ◽

pp. 99-110 ◽

Cited By ~ 2

Author(s):

Hannes Alex ◽

Norbert Steinfeldt ◽

Klaus Jähnisch ◽

Matthias Bauer ◽

Sandra Hübner

Keyword(s):

Catalytic Activity ◽

Benzyl Alcohol ◽

Aerobic Oxidation ◽

X Ray ◽

X Ray Scattering ◽

Oxidation Of Benzyl Alcohol ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Selective Aerobic Oxidation

AbstractNanoparticles (NP) have specific catalytic properties, which are influenced by parameters like their size, shape, or composition. Bimetallic NPs, composed of two metal elements can show an improved catalytic activity compared to the monometallic NPs. We, herein, report on the selective aerobic oxidation of benzyl alcohol catalyzed by unsupported Pd/Au and Pd NPs at atmospheric pressure. NPs of varying compositions were synthesized and characterized by UV/Vis spectroscopy, transmission electron microscopy (TEM), and small-angle X-ray scattering (SAXS). The NPs were tested in the model reaction regarding their catalytic activity, stability, and recyclability in batch and continuous procedure. Additionally, in situ extended X-ray absorption fine structure (EXAFS) measurements were performed in order to get insight in the process during NP catalysis.

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Characterization of columns grown during KrF laser micromachining of Al2O3–TiC ceramics

Journal of Materials Research ◽

10.1557/jmr.2003.0154 ◽

2003 ◽

Vol 18 (5) ◽

pp. 1123-1130 ◽

Cited By ~ 6

Author(s):

V. Oliveira ◽

R. Vilar

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Laser Pulses ◽

Formation Mechanisms ◽

X Ray ◽

Reducing Conditions ◽

Transmission Electron ◽

Column Formation ◽

Krf Laser

This paper aims to contribute to the understanding of column formation mechanisms in Al2O3–TiC ceramics micromachined using excimer lasers. Chemical and structural characterization of columns grown in Al2O3–TiC composite processed with 200 KrF laser pulses at 10 J/cm2 was carried out by scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy, and x-ray diffraction analysis. Fully developed columns consist of a core of unprocessed material surrounded by an outer layer of Al2TiO5, formed in oxidizing conditions, and an inner layer, formed in reducing conditions, composed of TiC and Al3Ti or an AlTi solid solution. Possible mechanisms of column formation are discussed.

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