Tuning the Non-Linear Optical Absorption Properties of Eu3+ Doped NiWO4 Nanostructures

Abstract NiWO4 nanostructures doped with different ratios of Eu3+ have been prepared by a chemical precipitation method. The influence of Eu3+ on NiWO4 nanostructures were characterized using X-ray diffraction (XRD), UV-visible diffuse reflectance spectra, scanning electron microscopy (SEM) and Raman. XRD patterns display that the samples crystallize to monoclinic wolframite structure. SEM images reveal that the particles are well uniformly dispersed with average particle size lies around 40-50nm. Third-order nonlinear optical properties were studied by a Z-scan technique at 532 nm using continuous wave diode pumped Nd:YAG laser. Open and closed aperture results reveal the nanostructures to possess reverse saturation absorption and negative nonlinear refraction. The calculated absorption coefficients (β), imaginary part of third-order susceptibilities Imχ(3) are in the order of 10-6(cm/W) and 10-7 esu. These results indicated that the synthesized nanostructures could be promising materials for optical device applications.

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Third Order Nonlinear Optical Characteristics of Er3+ doped BaMoO4 Nanostructures

10.21203/rs.3.rs-289218/v1 ◽

2021 ◽

Author(s):

RA sharath ◽

K Mani rahulan ◽

N Angeline Little Flower ◽

annie sujatha ◽

g vinitha ◽

...

Keyword(s):

Nonlinear Optical ◽

Continuous Wave ◽

Visible Region ◽

Chemical Precipitation ◽

Precipitation Method ◽

Third Order ◽

Fluorescence Measurements ◽

Device Applications ◽

Nonlinear Optical Device ◽

Xrd Patterns

Abstract We report the third order nonlinear optical properties of Er3+-doped BaMoO4 nanostructures, and its dependence on Er dopant concentration. BaMoO4 nanostructures with different concentration of Er were synthesized by chemical precipitation method and were characterized by UV-Vis absorption, X-ray diffraction (XRD), transmission electron microscopy (TEM) and fluorescence measurements. The incorporation of Er ions shifted the absorption band of BaMoO4 towards higher wavelength and enhanced the light absorption in the visible region. XRD patterns showed that the powders crystallize in scheelite-type tetragonal structure. The nonlinear optical behavior of the nanostructures was investigated by a Z-scan technique at 532 nm using continuous wave Nd:YAG laser. Experimental results suggested that the addition of Er can considerably enhance the nonlinear absorption and refractive index coefficients of BaMoO4 which could be used as a potential for nonlinear optical device applications.

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Synthesis and characterization of ZnTe nanoparticles

Nepal Journal of Science and Technology ◽

10.3126/njst.v17i1.25054 ◽

2016 ◽

Vol 17 (1) ◽

pp. 1-3 ◽

Cited By ~ 1

Author(s):

Sujan Dhungana ◽

Bhoj Raj Paudel ◽

Surendra K. Gautam

Keyword(s):

Particle Size ◽

Field Effect Transistors ◽

Average Particle Size ◽

Precursor Solution ◽

Chemical Precipitation ◽

Precipitation Method ◽

Average Particle ◽

X Ray Diffraction ◽

Zinc Compounds ◽

Transmission Electron

In this work, we report the ZnTe semiconductor nanoparticles (NPs) prepared by aqueous chemical precipitation method using the tellurium precursor solution with different zinc compounds. Three batches of ZnTe NPs were synthesized to study the effect of dilution on the size and phase purity of ZnTe. The influence of source compounds and concentrations of the size and structure of NPs were studied. ZnTe NPs have great applications as field-effect transistors and photodetectors. The existing controversy regarding the crystalline structure of ZnTe NPs, whether it is cubic or hexagonal, has been resolved using X-ray Diffraction (XRD) data. The ZnTe NPs possess cubic structure, which is also confirmed by Electron Diffraction (ED) pattern. The average particle size determined from XRD data with the help of Debye-Scherrer equation is about 6 nm. The particle size can be further verified by Transmission Electron Microscopy (TEM) studies.

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Study of structural, morphological, optical and electroluminescent properties of undoped ZnO nanorods grown by a simple chemical precipitation

Materials Science-Poland ◽

10.1515/msp-2015-0112 ◽

2015 ◽

Vol 33 (4) ◽

pp. 751-759 ◽

Cited By ~ 17

Author(s):

A. Singh ◽

H.L. Vishwakarma

Keyword(s):

Crystallite Size ◽

Threshold Voltage ◽

Room Temperature ◽

Zno Nanorods ◽

Average Particle Size ◽

Chemical Precipitation ◽

Absorption Peak ◽

Precipitation Method ◽

Average Particle ◽

Simple Chemical

AbstractIn this work, zinc oxide (ZnO) nanorods were obtained by a simple chemical precipitation method in the presence of capping agent: polyvinyl pyrrolidone (PVP) at room temperature. X-ray diffraction (XRD) result indicates that the synthesized undoped ZnO nanorods have hexagonal wurtzite structure without any impurities. It has been observed that the growth direction of the prepared ZnO nanorods is [1 0 1]. XRD analysis revealed that the nanorods have the crystallite size of 49 nm. Crystallite size is calculated by Debye-Scherrer formula and lattice strain is calculated by Williomson-Hall equation. Cell volume, Lorentz factor, Lorentz polarization factor, bond length, texture coefficient, lattice constants and dislocation density have also been studied. We also compared the interplanar spacings and relative peak intensities with their standard values at different angles. The scanning electron microscope (SEM) images confirmed the size and shape of these nanorods. It has been found that the diameter of the nanorods ranges from 1.52 μm to 1.61 μm and the length is about 4.89 μm. It has also been observed that at room temperature ultraviolet visible (UV-Vis) absorption band is around 355 nm (blue shifted as compared to the bulk). The average particle size has also been calculated by mathematical model of effective mass approximation equation, using UV-Vis absorption peak. Finally, the bandgap has been calculated using UV-absorption peak. Electroluminescence (EL) studies show that emission of light is possible at very small threshold voltage and it increases rapidly with increasing applied voltage. It is seen that smaller ZnO nanoparticles give higher electroluminescence brightness starting at lower threshold voltage. The brightness is also affected by increasing the frequency of AC signal.

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Enhanced oral bioavailability of nisoldipine-piperine-loaded poly-lactic-co-glycolic acid nanoparticles

Nanotechnology Reviews ◽

10.1515/ntrev-2017-0151 ◽

2017 ◽

Vol 6 (6) ◽

pp. 517-526 ◽

Cited By ~ 3

Author(s):

Permender Rathee ◽

Anjoo Kamboj ◽

Shabir Sidhu

Keyword(s):

Oral Bioavailability ◽

Drug Loading ◽

Average Particle Size ◽

Entrapment Efficiency ◽

Pharmacokinetic Interaction ◽

Precipitation Method ◽

Pharmacokinetic Studies ◽

Average Particle

AbstractBackground:Piperine helps in the improvement of bioavailability through pharmacokinetic interaction by modulating metabolism when administered with other drugs. Nisoldipine is a substrate for cytochrome P4503A4 enzymes. The study was undertaken to assess the influence of piperine on the pharmacokinetics and pharmacodynamics of nisoldipine nanoparticles in rats.Methods:Optimization studies of nanoparticles were performed using Taguchi L9 orthogonal array, and the nanoparticles were formulated by the precipitation method. The influence of piperine and nanoparticles was evaluated by means of in vivo kinetic and dynamic studies by oral administration in rats.Results:The entrapment efficiency, drug loading, ζ potential, and average particle size of optimized nisoldipine-piperine nanoparticles was 89.77±1.06%, 13.6±0.56%, −26.5 mV, and 132±7.21 nm, respectively. The in vitro release in 0.1 n HCl and 6.8 pH phosphate buffer was 96.9±0.48% and 98.3±0.26%, respectively. Pharmacokinetic studies showed a 4.9-fold increase in oral bioavailability and a >28.376±1.32% reduction in systemic blood pressure by using nanoparticles as compared to control (nisoldipine suspension) in Wistar rats.Conclusion:The results revealed that piperine being an inhibitor of cytochrome P4503A4 enzymes enhanced the bioavailability of nisoldipine by 4.9-fold in nanoparticles.

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Large 3rd Order Optical Kerr Nonlinearity in 2D PdSe2 Dichalcogenide Films for Integrated Nonlinear Photonic Chips

10.36227/techrxiv.14095685.v1 ◽

2021 ◽

Author(s):

David Moss

Keyword(s):

High Performance ◽

Nonlinear Optical ◽

Laser Intensity ◽

Nonlinear Refraction ◽

Kerr Nonlinearity ◽

Photonic Devices ◽

Closed Aperture ◽

Third Order ◽

Limiting Behaviour ◽

Incident Laser Intensity

As a novel layered noble metal dichalcogenide material, palladium diselenide (PdSe2) has attracted wide interest due to its excellent optical and electronic properties. In this work, a strong third-order nonlinear optical response of 2D PdSe2 films is reported. We conduct both open-aperture (OA) and closed-aperture (CA) Z-scan measurements with a femtosecond pulsed laser at 800 nm to investigate the nonlinear absorption and nonlinear refraction, respectively. In the OA experiment, we observe optical limiting behaviour originating from large two photo absorption (TPA) in the PdSe2 film of β = 3.26 ×10-8 m/W. In the CA experiment, we measure a peak-valley response corresponding to a large and negative Kerr nonlinearity of n2 = -1.33×10-15 m2/W – two orders of magnitude larger than bulk silicon. In addition, the variation of n2 as a function of laser intensity is also characterized, with n2 decreasing in magnitude when increasing incident laser intensity, becoming saturated at n2 = -9.96×10-16 m2/W at high intensities. Our results show that the extraordinary third-order nonlinear optical properties of PdSe2 have strong potential for high-performance nonlinear photonic devices.

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Effect of adding TiO2 nanoparticles on the SEM morphology and mechanical properties of conventional heat-cured acrylic resin

Journal of Dental Research Dental Clinics Dental Prospects ◽

10.15171/joddd.2019.036 ◽

2019 ◽

Vol 13 (3) ◽

pp. 234-240

Author(s):

Elnaz Moslehifard ◽

Mahmood Robati Anaraki ◽

Saeed Shirkavand

Keyword(s):

Impact Strength ◽

Tio2 Nanoparticles ◽

Cross Sections ◽

Average Particle Size ◽

Acrylic Resin ◽

Mechanical Tests ◽

Average Particle ◽

Sem Images ◽

Tio2 Nps ◽

The Impact

Background. The current study evaluated the compressive, flexural and impact strengths of heat-cured acrylic resins reinforced by TiO2 nanoparticles (NPs). Methods. TiO2 NPs were provided and characterized using scanning electron microscopy (SEM) to determine their morphology and crystalline structure. For three mechanical tests, 12 acrylic resin groups (n=9), totaling 108 specimens, were prepared using a special mold for each test, with TiO2 nanoparticle contents of 0, 0.5, 1 or 2 wt% in different groups. After curing, the compressive, flexural and impact strengths of the specimens were examined according to ISO 1567. Results. In the SEM and XRD study of TiO2 NPs, anatase was identified as the major crystalline phase followed by rutile (average particle size: 20.4 nm). SEM images showed that the nanocomposite with 1 wt% NPs had a more homogenized blend. 1 wt% TiO2 nanocomposite exhibited a higher, but non-significant, impact strength compared to the controls. ANOVA showed significant differences in the impact and flexural strengths between nanocomposites with various contents of TiO2 NPs. Conclusion. The nanocomposite with 1 wt% TiO2 NPs exhibited fewer micro-pores and micro-cracks in the SEM cross-sections. A non-significant increase was also observed in the impact strength with TiO2 NPs at 1 wt%. Further increase in TiO2 NPs decreased both the impact and flexural strengths. The compressive strength of the heat-cured acrylic resin was not affected by the incorporation of NPs.

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Preparation and characterization of domperidone nanoparticles for dissolution improvement

Iraqi Journal of Pharmaceutical Sciences ( P-ISSN 1683 - 3597 E-ISSN 2521 - 3512) ◽

10.31351/vol27iss1pp39-52 ◽

2018 ◽

Vol 27 (1) ◽

pp. 39-52

Author(s):

Mohammed Sabar Al-lami ◽

Malath H. Oudah ◽

Firas A. Rahi

Keyword(s):

Particle Size ◽

Average Particle Size ◽

In Vitro Release ◽

Methyl Cellulose ◽

Precipitation Method ◽

Average Particle ◽

Antisolvent Precipitation ◽

Stirring Time

This study was carried out to prepare and characterize domperidone nanoparticles to enhance solubility and the release rate. Domperidone is practically insoluble in water and has low and an erratic bioavailability range from 13%-17%. The domperidone nanoparticles were prepared by solvent/antisolvent precipitation method at different polymer:drug ratios of 1:1 and 2:1 using different polymers and grades of poly vinyl pyrolidone, hydroxy propyl methyl cellulose and sodium carboxymethyl cellulose as stabilizers. The effect of polymer type, ratio of polymer:drug, solvent:antisolvent ratio, stirring rate and stirring time on the particle size, were investigated and found to have a significant (p? 0.05) effect on particle size. The best formula was obtained with lowest average particle size of 84.05. This formula was studied for compatibility by FTIR and DSC, surface morphology by FESEM and crystalline state by XRPD. Then domperidone nanoparticles were formulated into a simple capsule dosage form in order to study of the in vitro release of drug from nanoparticles in comparison raw drug and mixture of polymer:drug ratios of 2:1. The release of domperidone from best formula was highly improved with a significant (p? 0.05) increase.

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Effect of Nanosized Colloidal Copper on Cotton Fabric

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892501000500301 ◽

2010 ◽

Vol 5 (3) ◽

pp. 155892501000500 ◽

Cited By ~ 15

Author(s):

D.P. Chattopadhyay ◽

B.H. Patel

Keyword(s):

Particle Size ◽

Cotton Fabric ◽

Colloidal Solution ◽

Chemical Reduction ◽

Average Particle Size ◽

Particle Size Analysis ◽

Nano Particles ◽

Size Analysis ◽

Average Particle ◽

Sem Images

This research deals with the synthesis of nanosized copper as colloidal solution and its application to cotton fabric. Copper nano colloids were prepared by chemical reduction of copper salt using sodium borohydride as reducing agent in presence of tri-sodium citrate. The size and size distribution of the particles were examined by particle size analyzer and the morphology of the synthesized particles was examined by SEM and AFM techniques. X-ray fluorescence spectroscopy detected the presence of copper in the treated fabric. The results of particle size analysis showed that the average particle size varied from 60 nm to 100 nm. The nano copper treated cotton was subjected to soil burial test for the assessment of its resistance towards microbial attack. SEM images of treated fabric indicate copper nano particles are well dispersed on the surface of the specimens. The treatments of nano copper colloidal solution on cotton not only improve its antimicrobial efficiency but also influenced the tensile strength of the fabric sample positively. The treatment was found to enhance the color depth and fastness properties of direct dyed cotton fabric samples.

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Olive Leaves as Biotemplates for Enhanced Solar-Light Harvesting by a Titania-Based Solid

Nanomaterials ◽

10.3390/nano10061057 ◽

2020 ◽

Vol 10 (6) ◽

pp. 1057

Author(s):

Jesús Hidalgo-Carrillo ◽

Juan Martín-Gómez ◽

M. Carmen Herrera-Beurnio ◽

Rafael C. Estévez ◽

Francisco J. Urbano ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Electron Paramagnetic Resonance Spectroscopy ◽

Average Particle Size ◽

Solar Irradiation ◽

Bet Surface Area ◽

Resonance Spectroscopy ◽

Average Particle ◽

Olive Leaves ◽

Sem Images ◽

X Ray

Olive leaves (by-product from olive oil production in olive mills) were used as biotemplates to synthesize a titania-based artificial olive leaf (AOL). Scanning electron microscopy (SEM) images of AOL showed the successful replication of trichomes and internal structure channels present in olive leaves. The BET surface area of AOL was 52 m2·g−1. X-ray diffraction (XRD) and Raman spectra revealed that the resulting solid was in the predominantly-anatase crystalline form (7.5 nm average particle size). Moreover, the synthesis led to a red-shift in light absorption as compared to reference anatase (gap energies of 2.98 and 3.2 eV, respectively). The presence of surface defects (as evidenced by X-ray photoelectron spectroscopy, XPS, and electron paramagnetic resonance spectroscopy, EPR) and doping elements (e.g., 1% nitrogen, observed by elemental analysis and XPS) could account for that. AOL was preliminarily tested as a catalyst for hydrogen production through glycerol photoreforming and exhibited an activity 64% higher than reference material Evonik P25 under solar irradiation and 144% greater under ultraviolet radiation (UV).

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Morphology-Controlled CaCO3 Nanostructures by Modified Co-Precipitation in Pulsed Mode

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.752-753.148 ◽

2015 ◽

Vol 752-753 ◽

pp. 148-153

Author(s):

M.M. Nassar ◽

Taha Ebrahiem Farrag ◽

M.S. Mahmoud ◽

Sayed Abdelmonem

Keyword(s):

Particle Size ◽

Calcium Carbonate ◽

Rotation Speed ◽

Average Particle Size ◽

Calcium Nitrate ◽

Precipitation Method ◽

Average Particle ◽

X Ray ◽

Co Precipitation ◽

Pulsed Mixing

Calcium carbonate nanoparticles and nanorods were synthesized by precipitation from saturated sodium carbonate and calcium nitrate aqueous solutions through co precipitation method. A new rout of synthesis was done by both using pulsed mixing method and controlling the addition of calcium nitrate. The effect of the agitation speed, and the temperature on particle size and morphology were investigated. Particles were characterized using X-ray Microanalysis, X-ray analysis (XRD) and scanning electron microscopy (SEM). The results indicated that increasing the mixer rotation speed from 3425 to 15900 (rpm) decreases the average particle size to 64±7 nm. A rapid nucleation then aggregation induced by excessive shear force phenomena could explain this observation. Moreover, by increasing the reaction temperature, the products were converted from nanoparticle to nanorods. The maximum attainable aspect ratio was 6.23 at temperature of 75°C and rotation speed of 3425. Generally, temperature raise promoted a significant homoepitaxial growth in one direction toward the formation of calcite nanorods. Overall, this study can open new avenues to control the morphology of the calcium carbonate nanostructures.

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