Silica–titania hybrids for structurally robust inverse opals with controllable refractive index

2020 ◽  
Vol 8 (1) ◽  
pp. 109-116
Author(s):  
Katherine R. Phillips ◽  
Tanya Shirman ◽  
Michael Aizenberg ◽  
Grant T. England ◽  
Nicolas Vogel ◽  
...  
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Inverse Opal ◽  
Structural And Optical Properties ◽  
Inverse Opals ◽  
Silica And Titania

Combining silica and titania precursors at varying ratios yields uniform hybrid inverse opal structures with adjustable structural and optical properties.

scholarly journals Deposition Time induced Structural and Optical Properties of Lead Tin Sulphide Thin Films

2021 ◽  
pp. 455-458
Author(s):  
J. Damisa ◽  
J. O. Emegha ◽  
I. L. Ikhioya
Keyword(s):  
Thin Films ◽  
Refractive Index ◽  
Optical Properties ◽  
Absorption Coefficient ◽  
Tin Oxide ◽  
Deposition Time ◽  
Deposition Process ◽  
Structural And Optical Properties ◽  
X Ray ◽  
Prepared Material

Lead tin sulphide (Pb-Sn-S) thin films (TFs) were deposited on fluorine-doped tin oxide (FTO) substrates via the electrochemical deposition process using lead (II) nitrate [Pb(NO3)2], tin (II) chloride dehydrate [SnCl2.2H2O] and thiacetamide [C2H5NS] precursors as sources of lead (Pb), tin (Sn) and sulphur (S). The solution of all the compounds was harmonized with a stirrer (magnetic) at 300k. In this study, we reported on the improvements in the properties (structural and optical) of Pb-Sn-S TFs by varying the deposition time. We observed from X-ray diffractometer (XRD) that the prepared material is polycrystalline in nature. UV-Vis measurements were done for the optical characterizations and the band gap values were seen to be increasing from 1.52 to 1.54 eV with deposition time. In addition to this, the absorption coefficient and refractive index were also estimated and discussed.

The Structure and Optical Properties of Dy3+ Doped PLZT Ceramics

2005 ◽  
Vol 475-479 ◽  
pp. 1189-1192
Author(s):  
Yong Zhang ◽  
Ai Li Ding ◽  
Qing Rui Yin
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Optical Transmission ◽  
Single Phase ◽  
Tetragonal Structure ◽  
Structural And Optical Properties ◽  
Method Effects

The polycrystalline Dy3+ doped PLZT ceramics with compositional formula [Pb0.88 (La1-xDyx)0.12](Zr0.40Ti0.60)O3, were prepared by hot-pressed method. Effects of Dy3+ substitution on structural and optical properties were report here. All the samples have single phase with tetragonal structure, and the tetragonality was increased with content increased. As Dy3+ content increased, the optical transmission was found to decrease, and the refractive index was raised slightly.

Structural and Optical Properties of Electro-Chromic Nickel Oxide Films

1996 ◽  
Vol 441 ◽  
Author(s):  
Kensuke Murai ◽  
Yoshiyuki Sato ◽  
Shigeharu Tamura
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Chemical Composition ◽  
Nickel Oxide ◽  
Spin Coating ◽  
Oxide Films ◽  
Structural And Optical Properties ◽  
Before And After ◽  
Nickel Oxide Films

AbstractThe electro-chromic behavior of nickel oxide (NiOx) films, prepared by spin-coating, were analyzed for their structual and optical properties before and after cycling procedure in electrolyte. It was found that the chemical composition, refractive index, and thickness of the film changes significantly on hydration.

scholarly journals Structural and optical properties for PVA- PEG-MnCl2 composites

2019 ◽  
Vol 15 (32) ◽  
pp. 99-113
Author(s):  
Mahdi Hasan Suhail
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Polymer Blend ◽  
Extinction Coefficient ◽  
Energy Gap ◽  
Dielectric Constants ◽  
Structural And Optical Properties ◽  
Optical Energy Gap ◽  
X Ray ◽  
Amorphous Structures

Polymer films of PEG and PVA and their blend with differentconcentrations of MnCl2 (0, 2, 4, 6 and 10 %.wt) were study usingcasting technique. The X-ray spectra of pure PEG, PVA andPVA:PEG films and with addition of 2% concentrations from(MnCl2) show amorphous structures. The results for FTIR show theinteraction between the filler and polymer blend results indecreasing crystallinity with rich amorphous phase. Thisamorphous nature confirms the complexation between the filler andthe polymer blend. The optical properties of (PVA:PEG/MnCl2)contain the recording of absorbance (A) and explain that theabsorption coefficient (α), refractive index (n), extinction coefficient(ko) and the dielectric constants (real and imaginary part) increasewith increasing the concentration of Composite (PVA:PEG/MnCl2).The optical energy gap for electrons transitions both are direct andindirect allowed.

scholarly journals Fluoropolymer-Containing Opals and Inverse Opals by Melt-Shear Organization

Molecules ◽  
2019 ◽  
Vol 24 (2) ◽  
pp. 333 ◽  
Author(s):  
Julia Kredel ◽  
Christian Dietz ◽  
Markus Gallei
Keyword(s):  
Optical Properties ◽  
Optical Sensors ◽  
Matrix Material ◽  
Functional Materials ◽  
Building Blocks ◽  
Core Shell ◽  
Inverse Opal ◽  
Shell Material ◽  
Inverse Opals ◽  
Structural Colors

The preparation of highly ordered colloidal architectures has attracted significant attention and is a rapidly growing field for various applications, e.g., sensors, absorbers, and membranes. A promising technique for the preparation of elastomeric inverse opal films relies on tailored core/shell particle architectures and application of the so-called melt-shear organization technique. Within the present work, a convenient route for the preparation of core/shell particles featuring highly fluorinated shell materials as building blocks is described. As particle core materials, both organic or inorganic (SiO2) particles can be used as a template, followed by a semi-continuous stepwise emulsion polymerization for the synthesis of the soft fluoropolymer shell material. The use of functional monomers as shell-material offers the possibility to create opal and inverse opal films with striking optical properties according to Bragg’s law of diffraction. Due to the presence of fluorinated moieties, the chemical resistance of the final opals and inverse opals is increased. The herein developed fluorine-containing particle-based films feature a low surface energy for the matrix material leading to good hydrophobic properties. Moreover, the low refractive index of the fluoropolymer shell compared to the core (or voids) led to excellent optical properties based on structural colors. The herein described fluoropolymer opals and inverse opals are expected to pave the way toward novel functional materials for application in fields of coatings and optical sensors.

scholarly journals Effect of Ag-Nanoparticles Doped in Polyvinyl Alcohol on the Structural and Optical Properties of PVA Films

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Mahshad Ghanipour ◽  
Davoud Dorranian
Keyword(s):  
Silver Nanoparticles ◽  
Refractive Index ◽  
Optical Properties ◽  
Complex Refractive Index ◽  
Composite Films ◽  
Dielectric Medium ◽  
Bandgap Energy ◽  
Optical Parameters ◽  
Structural And Optical Properties ◽  
Dispersion Parameters

The effect of silver nanoparticles doped in PVA on the structural and optical properties of composite films is studied experimentally. Samples are PVA films of 0.14 mm thickness doped with different sizes and concentrations of silver nanoparticles. Structural properties are studied using X-ray diffraction and FTIR spectrum. Using the reflectance and transmittance of samples, the effect of doped nanoparticles and their concentration on optical parameters of PVA films include absorption coefficient, optical bandgap energy, complex refractive index, complex dielectric function, complex optical conductivity, and relaxation time is extracted and discussed. The dispersion of the refractive index of films in terms of the single oscillator Wemple-DiDomenico (WD) model is investigated and the dispersion parameters are calculated. Results show that by doping silver nanoparticles in PVA, number of Bragg’s planes in the structure of polymer and its crystallinity are increased noticeably. Ag–O bonds are formed in the films and the bandgap energy of samples is decreased. Calculations based on WD model confirm that by doping nanoparticles, the anion strength of PVA as a dielectric medium is decreased.

Characteristics of ultraviolet-assisted pulsed-laser-deposited Y2O3 thin films

2000 ◽  
Vol 15 (2) ◽  
pp. 488-494 ◽  
Author(s):  
V. Craciun ◽  
E. S. Lambers ◽  
N. D. Bassim ◽  
R. K. Singh ◽  
D. Craciun
Keyword(s):  
Thin Films ◽  
Refractive Index ◽  
Optical Properties ◽  
Pulsed Laser Deposition ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Structural And Optical Properties ◽  
Uv Illumination ◽  
Substrate Temperatures

The properties of thin Y2O3 films grown using an in situ ultraviolet (UV)-assisted pulsed laser deposition (PLD) technique were studied. With respect to Y2O3 films grown by conventional PLD under similar conditions but without UV illumination, the UVPLD-grown films exhibited better structural and optical properties, especially for lower substrate temperatures, from 340 to 400 °C. These layers were highly crystalline and textured along the (111) direction, and their refractive index values were similar to those of reference Y2O3 layers. They also exhibited a better stoichiometry and contained less physisorbed oxygen than the conventional PLD-grown layers.

STRUCTURAL AND OPTICAL PROPERTIES OF SURFACTANT ASSISTED SiO2-TiO2 HYBRID MATRIX FOR PH SENSING: SOL-GEL APPROACH

2016 ◽  
Vol 78 (3) ◽  
Author(s):  
Shumaila Islam ◽  
Noriah Bidin ◽  
Saira Riaz ◽  
Shahzad Naseem
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
High Surface ◽  
Sol Gel ◽  
Ph Sensing ◽  
Structural And Optical Properties ◽  
Functional Coating ◽  
Hybrid Matrix ◽  
Surfactant Assisted ◽  
Low Refractive Index

Structural and optical properties of surfactant-assisted SiO2-TiO2 hybrid matrix as a highly responsive optical sensing material by sol-gel method are investigated. Microscopic results indicate the uniform morphology with large pores without any cracks. Matrices have a high surface area (489–342 m2/g), which has more capability to sense the broader pH range. From UV–visible spectroscopy, it is found that after encapsulation, matrix has ~ 78 % optical transparency with low refractive index of 1.44 corresponding to thickness 138.7 nm. Sensing analysis revealed that the prepared coating has good sensitivity at pH 12 and fast response time. Low refractive index and highly porous matrix, combined for achieving a good responsive optical chemical sensors. This research also opens an aveanue for ths material to be considered as a functional coating.

Modification of optical properties of PC-PBT/Cr2O3 and PC-PBT/CdS nanocomposites by gamma irradiation

2020 ◽  
Vol 92 (2) ◽  
pp. 20402
Author(s):  
Kaoutar Benthami ◽  
Mai ME. Barakat ◽  
Samir A. Nouh
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Band Gap ◽  
Color Difference ◽  
Band Gap Energy ◽  
Polybutylene Terephthalate ◽  
Γ Irradiation ◽  
Gap Energy ◽  
Vis Spectroscopy ◽  
Oxygen Atoms

Nanocomposite (NCP) films of polycarbonate-polybutylene terephthalate (PC-PBT) blend as a host material to Cr2O3 and CdS nanoparticles (NPs) were fabricated by both thermolysis and casting techniques. Samples from the PC-PBT/Cr2O3 and PC-PBT/CdS NCPs were irradiated using different doses (20–110 kGy) of γ radiation. The induced modifications in the optical properties of the γ irradiated NCPs have been studied as a function of γ dose using UV Vis spectroscopy and CIE color difference method. Optical dielectric loss and Tauc's model were used to estimate the optical band gaps of the NCP films and to identify the types of electronic transition. The value of optical band gap energy of PC-PBT/Cr2O3 NCP was reduced from 3.23 to 3.06 upon γ irradiation up to 110 kGy, while it decreased from 4.26 to 4.14 eV for PC-PBT/CdS NCP, indicating the growth of disordered phase in both NCPs. This was accompanied by a rise in the refractive index for both the PC-PBT/Cr2O3 and PC-PBT/CdS NCP films, leading to an enhancement in their isotropic nature. The Cr2O3 NPs were found to be more effective in changing the band gap energy and refractive index due to the presence of excess oxygen atoms that help with the oxygen atoms of the carbonyl group in increasing the chance of covalent bonds formation between the NPs and the PC-PBT blend. Moreover, the color intensity, ΔE has been computed; results show that both the two synthesized NCPs have a response to color alteration by γ irradiation, but the PC-PBT/Cr2O3 has a more response since the values of ΔE achieved a significant color difference >5 which is an acceptable match in commercial reproduction on printing presses. According to the resulting enhancement in the optical characteristics of the developed NCPs, they can be a suitable candidate as activate materials in optoelectronic devices, or shielding sheets for solar cells.

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