Solubility and spectrochemical characteristics of synthetic chernikovite and meta-ankoleite

1996 ◽  
Vol 60 (402) ◽  
pp. 759-766 ◽  
Author(s):  
Laurent Van Haverbeke ◽  
Renaud Vochten ◽  
Karel Van Springel
Keyword(s):  
Chemical Analysis ◽  
Band Gap ◽  
Infrared Spectra ◽  
Ionic Species ◽  
Band Gap Energy ◽  
Luminescence Spectra ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gap Energy ◽  
High Crystallinity

AbstractChernikovite and meta-ankoleite were synthesized with a relatively high crystallinity and the compounds were identified by means of chemical analysis and X-ray diffraction. The infrared spectra were recorded and the bands assigned. From the luminescence spectra, the band-gap energy for both compounds was calculated as 2.35 eV, indicating that they must be considered as insulators. The dependence of the solubilities of these compounds on the acidity of the solution was studied, and the dominant ionic species were determined. The pKsp values of chernikovite and meta-ankoleite were found to be 22.73±0.24 and 24.30±0.81 respectively.

Study on Band Gap Energy of F Doped TiO2 Nanotubes

2017 ◽  
Vol 889 ◽  
pp. 234-238
Author(s):  
Mohd Hasmizam Razali ◽  
Nur Arifah Ismail ◽  
Mahani Yusoff
Keyword(s):  
Band Gap ◽  
Diffuse Reflectance Spectroscopy ◽  
Small Diameter ◽  
Ultra Violet ◽  
Band Gap Energy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gap Energy ◽  
Transmission Electron ◽  
Xrd Patterns

Pure and F doped TiO2 nanotubes was synthesized using simple hydrothermal method. The hydrothermal was conducted using teflon-liner autoclave and maintained at 150oC for 24 hours. The characterization of synthesised product was carried out using x-ray diffraction (XRD), transmission electron microscope (TEM), energy dispersive of x-ray spectroscopy (EDX) and ultra violet – visible light diffuse reflectance spectroscopy (UV-Vis DRS) for band gap measurements. XRD patterns indicated that anatase TiO2 phase was remained after F doping suggested that fluorine was highly dispersed into TiO2 by substituted with O in the TiO2 lattice to formed TiO2-xFx solid solution. Morphology investigation using TEM found out small diameter of nanotubes structure within 8 – 10 nm of pure and F doped TiO2 nanotubes. The band gap energy (Eg) of both nanotubes samples were almost similar proposing that F doping does not modify the band gap energy.

Effect of bath temperature on the chemical bath deposition of PbSe thin films

1970 ◽  
Vol 6 (2) ◽  
pp. 126-132 ◽  
Author(s):  
Anuar Kassim ◽  
Tan Wee Tee ◽  
Ho Soon Min ◽  
Shanthi Monohorn ◽  
Saravanan Nagalingam
Keyword(s):  
Thin Films ◽  
Band Gap ◽  
Chemical Bath Deposition ◽  
Lead Nitrate ◽  
Bath Temperature ◽  
Band Gap Energy ◽  
Sodium Selenate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gap Energy

PbSe thin films are prepared by chemical bath deposition technique over microscope glass substrates from an aqueous acidic bath containing lead nitrate and sodium selenate. The influence of bath temperature on the properties of PbSe film is investigated. The X-ray diffraction analysis showed the deposited films were polycrystalline and having the (111) orientation. The surface morphology study revealed that the grains have cubic shape crystal. The band gap energy was decreased from 2.0 to 1.3 eV as the bath temperature was increased from 40 to 80°C. The films deposited at 80°C showed good crystallinity and uniformly distributed over the surface of substrate with larger grain sizes. Therefore, the optimum bath temperature is 80°C. Keywords: Lead selenide; X-ray diffraction; Band gap energy; Chemical bath deposition; Thin films DOI: 10.3126/kuset.v6i2.4021Kathmandu University Journal of Science, Engineering and Technology Vol.6. No II, November, 2010, pp.126-132

scholarly journals PbI2 Single Crystal Growth and Its Optical Property Study

Crystals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 589 ◽  
Author(s):  
Lin ◽  
Guo ◽  
Dai ◽  
Lin ◽  
Hsu
Keyword(s):  
Band Gap ◽  
Chemical Vapor ◽  
Band Gap Energy ◽  
Chemical Vapor Transport ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gap Energy ◽  
Photoelectric Properties ◽  
Metal Semiconductor Metal ◽  
Excitonic Transition

In this work, we used the chemical vapor transport (CVT) method to grow PbI2 crystals using iodine as a self-transporting agent. The crystals’ structure, composition, and uniformity were confirmed by X-ray diffraction (XRD) and electron probe microanalysis (EPMA) measurements. We investigated the band gap energy using absorption spectroscopy measurements. Furthermore, we explored the temperature dependence of the band gap energy, which shifts from 2.346 eV at 300 K to 2.487 eV at 20 K, and extracted the temperature coefficients. A prototype photodetector with a lateral metal–semiconductor–metal (MSM) configuration was fabricated to evaluate its photoelectric properties using a photoconductivity spectrum (PC) and persistent photoconductivity (PPC) experiments. The resonance-like PC peak indicates the excitonic transition in absorption. The photoresponse ILight/IDark-1 is up to 200%.

Physical Properties Study of TiO2 Nanoparticle Synthesis via Hydrothermal Method Using TiO2 Microparticles as Precursor

2013 ◽  
Vol 772 ◽  
pp. 365-370 ◽  
Author(s):  
Mohd Hasmizam Razali ◽  
M.N. Ahmad-Fauzi ◽  
Abdul Rahman Mohamed ◽  
Srimala Sreekantan
Keyword(s):  
Electron Microscopy ◽  
Band Gap ◽  
Hydrothermal Method ◽  
Hydrothermal Reaction ◽  
Anatase Phase ◽  
Nanoparticle Synthesis ◽  
Band Gap Energy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gap Energy

Titanium dioxide (TiO2) nanoparticles were successfully synthesised by hydrothermal method using TiO2 microparticle powder (Merck) as precursor. TiO2 microparticles powder (~160 nm) was mixed with 10 M NaOH and treated hydrothermally at 150 °C and 2 MPa pressure in autoclave for 24 hours. After hydrothermal reaction was completed, the sample was washed, dried and heated at 500 °C for 2 hours to produce TiO2 nanoparticles. The synthesised nanoparticles were characterized using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and raman spectroscopy. UV-Vis DRS was used to determine the band gap energy. Field emissions and transmissions electron microscopy images revealed that nanoparticles obtained was about 14 nm. X-ray diffraction patterns showed that TiO2 nanoparticles were anatase phase (tetragonal). The band gap energy of TiO2 nanoparticles was determined to be 3.32 eV.

Effect of Cu Doped in MgO on Nanostructures and their Band Gap Energies

2019 ◽  
Vol 290 ◽  
pp. 323-328 ◽  
Author(s):  
Nor Fadilah Chayed ◽  
Norlida Kamarulzaman ◽  
Nurhanna Badar ◽  
Kelimah Elong
Keyword(s):  
Band Gap ◽  
Crystallite Size ◽  
Single Phase ◽  
Average Crystallite Size ◽  
Combustion Method ◽  
Band Gap Energy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gap Energy ◽  
Scanning Electron

Doping of the materials with other metals or transition metals will modify the properties of the nanomaterials. In this work, MgO and Cu doped MgO which are Mg0.95Cu0.05O and Mg0.90Cu0.10O nanomaterials are synthesized using a self-propagating combustion method. The samples are annealed at 900 °C for 24 hours. The phase and purity of the synthesized samples are studied using X-Ray Diffraction (XRD) and the result revealed that the samples are pure and single phase. The morphology and crystallite size of the pure samples are examined using Field Emission Scanning Electron Microscope (FESEM). The result shows polyhedral morphology with agglomeration of crystallite and average crystallite size of the samples is between 40 to 210 nm. The band gap obtained for MgO nanostructures is 6.38 eV which is lower than bulk MgO of 7.8 eV. The presence of Cu causes the narrowing the band gap energy of Mg0.95Cu0.05O and Mg0.90Cu0.10O samples to 4.28 eV and 3.35 eV respectively.

Effect of Detergent on the ZnO Nanorods Structures Synthesized via the Sol-Gel Method

2012 ◽  
Vol 545 ◽  
pp. 161-164
Author(s):  
Rusdi Roshidah ◽  
Abd Rahman Azilah ◽  
Norlida Kamarulzaman
Keyword(s):  
Band Gap ◽  
Optical Band Gap ◽  
Inorganic Material ◽  
Sol Gel ◽  
Zno Nanorods ◽  
Band Gap Energy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gap Energy ◽  
Thermogravimetric Analyzer

ZnO is known as an inorganic material that has a variety of morphologies. The morphologies of the ZnO are much influenced by the synthesis route. In this work, two ZnO nanomaterials were prepared by the sol-gel route and the effect of detergent on the morphology and optical band gap of ZnO materials were investigated. The synthesized ZnO materials were characterized using Simultaneous Thermogravimetric Analyzer (STA), X-ray Diffraction (XRD) and Field Emission Scanning Electron Microscope (FESEM). The UV-Vis spectrophotometer is used to determine the optical band gap. The results show that the presence of detergent affected the morphology of the ZnO from nanorods to nano-flakes. The band gap energy of the ZnO were also reduced from 3.14 ev to 2.98 eV from the nanorod to the nanoflakes.

Optical Properties of GaNAs Grown by MBE

1998 ◽  
Vol 3 ◽  
Author(s):  
G. Pozina ◽  
I. G. Ivanov ◽  
B. Monemar ◽  
J.V. Thordson ◽  
T.G. Andersson
Keyword(s):  
Optical Properties ◽  
Band Gap ◽  
Secondary Ion Mass Spectrometry ◽  
Nitrogen Concentration ◽  
Arsenic Concentration ◽  
Band Gap Energy ◽  
Optical Measurements ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gap Energy

Optical properties of the GaNxAs1−x layers grown on (001) GaAs substrates by molecular beam epitaxy have been studied. The samples can be classified into three categories with respect to the concentration of N, as determined by x-ray diffraction and secondary-ion mass spectrometry: (i) with doping nitrogen concentration, (ii) with average content of N less than 30 %, and (iii) with x close to 100 %. From optical measurements of photoluminescence and Raman scattering, combined with analysis of x-ray diffraction spectra, different phases are observed in the GaNxAs1−x layers: GaAs, GaN and the solid ternary solution GaNxAs1−x. We have estimated the fundamental band-gap energy in the GaNxAs1−x alloy with low nitrogen concentration (up to x = 0.04) from absorption measurements, and in GaNxAs1−x with low arsenic concentration (up to 1−x = 0.04) - from photoluminescence spectra. An analysis of the dependence of the experimental values of the GaNxAs1−x band-gap energy on the nitrogen composition indicates a constant bowing parameter b as large as b = -18 eV.

The Optical Performance of Holmium Oxide Doped Tellurite Glass for Potential Optical Fiber

2021 ◽  
Vol 317 ◽  
pp. 95-99
Author(s):  
Muhammad Noorazlan Abd Azis ◽  
Halimah Mohamed Kamari ◽  
Suriani Abu Bakar ◽  
Azlina Yahya ◽  
Umar Saad Aliyu
Keyword(s):  
Refractive Index ◽  
Band Gap ◽  
Tellurite Glass ◽  
Optical Band Gap ◽  
Band Gap Energy ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
Gap Energy ◽  
Xrd Method ◽  
Nonlinear Pattern

Borotellurite glass had been widely applied in the field of optical communications and devices. In this work, holmium oxides doped borotellurite glass had been successfully fabricated via conventional melt-quenched technique. The structural properties of holmium doped tellurite glass were found using x-ray diffraction (XRD) method. The nonexistence of sharp peaks in XRD pattern shows that the inclusion of holmium tellurite glass leads to the formation long range of disorderness. The optical properties of the glass system such as refractive index and optical band gap energy are investigated using UV-Vis spectrophotometer. The value of refractive index is found in nonlinear trend along with holmium oxides concentration. It is found that the refractive index is more than 2 at 0.01, 0.03 and 0.04 of holmium concentrations. The optical band gap energy was found in similar trend with refractive index which is in nonlinear pattern.

FeAl2O4 Nanopowders; Structural Analysis and Band Gap Energy

2017 ◽  
Vol 36 (8) ◽  
pp. 789-793 ◽  
Author(s):  
Morteza Enhessari
Keyword(s):  
Structural Analysis ◽  
Band Gap ◽  
Sol Gel ◽  
Band Gap Energy ◽  
Mixed Metal Oxide ◽  
Nanoscale Materials ◽  
X Ray Diffraction ◽  
Organic Precursor ◽  
Gap Energy ◽  
Acid Gel

AbstractNanoscale FeAl2O4 was successfully synthesized via sol–gel method. The sol constituents containing iron and aluminum cations were formed homogenously in stearic acid gel (formation of organic precursor). The pure structural analysis and the size of the spinels were confirmed by X-ray diffraction (XRD). It was observed that the size of the nanoscale materials obtained at around 30–40nm. The micrographs of FeAl2O4 evidenced the homogenous and nanosize formation of spinel. The semiconducting behavior of this mixed metal oxide was observed at 3.14eV based on the band gap energy (Eg). The final nanoscale materials exhibited a superparamagnetic behavior with a saturation magnetization of 9.8 emu/g at applied field of 10 kOe.

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