scholarly journals Effect of Annealing on Optical Properties of ZnO·LiF·B2O3 Glasses

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Susheel Arora ◽  
Virender Kundu ◽  
D. R. Goyal ◽  
A. S. Maan
Keyword(s):  
Optical Properties ◽  
Molecular Species ◽  
Urbach Energy ◽  
Optical Characterization ◽  
Optical Bandgap ◽  
Bandgap Energy ◽  
Nonbridging Oxygen ◽  
Different Temperatures ◽  
Optical Bandgap Energy ◽  
Quench Method

The Melt-quench method is used to synthesize zinc fluoroborate glasses with compositions xZnO·(40−x)LiF·60B2O3 (x=0, 5, 10, 15, and 20). Optical characterization was carried out to examine the variation of optical bandgap energy (Eg) and urbach energy (EU) with respect to the concentration for the samples annealed at different temperatures (300°C, 350°C, and 400°C). Annealing shows its effect on the samples with the variations in the values of Eg and EU. These variations are explained on the basis of formation of different molecular species like BO3- units, boroxol rings, and the change in the number of nonbridging oxygen atoms.

scholarly journals Effect of Stepwise Replacement of LiF by Bi2O3 and of Annealing on Optical Properties of LiF⋅B2O3 Glasses

ISRN Optics ◽  
2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Susheel Arora ◽  
Virender Kundu ◽  
D. R. Goyal ◽  
A. S. Maan
Keyword(s):  
Optical Properties ◽  
Band Gap ◽  
Optical Band Gap ◽  
Urbach Energy ◽  
Optical Characterization ◽  
Band Gap Energy ◽  
Gap Energy ◽  
Different Temperatures ◽  
Quench Method

Bismuth fluoroborate glasses with compositions xBi2O3⋅(40-x)LiF⋅60  B2O3  (x=0,5,10,15,  and  20) are synthesized by melt-quench method. Optical characterization was carried out to examine variation of optical band gap energy (Eg) and Urbach energy (EU) with respect to the concentration. It reflects the effect of stepwise replacement of non-oxide and less polarizable LiF by an oxide and more polarizable (Bi2O3) group on the optical properties of the samples. The value of Eg decreases with increase in concentration of Bi2O3. The samples were subjected to annealing at different temperatures (300°C, 350°C, and 400°C), and the effect of annealing on the optical properties of various samples was again studied. Annealing affects remarkably the values of Eg and EU in the samples with x=0.

Thickness Dependent Structural and Optical Properties of Cadmium Selenide Thin Films

2013 ◽  
Vol 665 ◽  
pp. 159-167
Author(s):  
M.S. Jani ◽  
H.S. Patel ◽  
J.R. Rathod ◽  
K.D. Patel ◽  
V.M. Pathak ◽  
...  
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Hexagonal Wurtzite Structure ◽  
Optical Bandgap ◽  
Bandgap Energy ◽  
Structural And Optical Properties ◽  
Structural Investigations ◽  
Glass Substrates ◽  
Optical Bandgap Energy ◽  
Different Thickness

In this paper structural and optical properties of CdSe thin films with different thickness deposited by thermal evaporation under vacuum onto glass substrates are presented. The structural investigations performed by means of XRD technique showed that the films have a polycrystalline and hexagonal (würtzite) structure. The values of some important parameters of the studied films (absorption coefficient and optical bandgap energy) are determined from transmission spectra. The values of the optical bandgap energy (Eg) calculated from the absorption spectra, ranged between 1.67 - 1.74 eV.

Doping and Annealing Effects on the Optical Bandgap of the Nickel Doped Copper Oxide Thin Films

2021 ◽  
Vol 16 (2) ◽  
pp. 243-248
Author(s):  
Fatmah S. Bahabri ◽  
Alaa Y. Mahmoud ◽  
Wafa A. Alghameeti
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Doping Concentration ◽  
Cupric Oxide ◽  
Optical Bandgap ◽  
Visible Range ◽  
Bandgap Energy ◽  
Direct Bandgap ◽  
Annealing Temperatures ◽  
Annealing Effects

In this work, we study the optical properties of the Nickel doped cupric oxide Ni-CuO thin films with Ni various doping concentrations (0, 20, 30, 50, 70, and 80%), at two different annealing temperatures; 200 and 400 °C. The absorbance and optical bandgap for the films are calculated and compared. We find that all films exhibit clear peaks in the visible range, with the increase in the absorptivity via increasing both annealing and Ni concentration. We also find that the annealing affects the shape of the absorbance peaks to be narrowed and blue shifted. Investigation on the direct bandgap energy shows that all films exhibit large direct gap; ranging from 3.87 to 4.01 eV. For non-annealed films, direct bandgap increases with increasing the Ni concentration, while for the annealed samples, the direct bandgap generally decreases by annealing, and with increasing the doping concentration. For the indirect bandgap analysis, the calculated values of the bandgap are ranging from 0.62 to 1.96 eV. We find that for non-annealed films, the indirect bandgap increases with increasing the doping concentration, while after annealing, the bandgap decreases with increasing the doping concentration for the annealing at 200 and 400 °C, with more decreasing in the gap at 400 °C.

Determination of optical bandgap energy and optical characteristics of Cd30Se50S20 thin film at various thicknesses

2022 ◽  
Vol 148 ◽  
pp. 107770
Author(s):  
Ammar Qasem ◽  
Mohamed S. Mostafa ◽  
H.A. Yakout ◽  
Mona Mahmoud ◽  
E.R. Shaaban
Keyword(s):  
Thin Film ◽  
Optical Bandgap ◽  
Optical Characteristics ◽  
Bandgap Energy ◽  
Optical Bandgap Energy

scholarly journals Fe2O3 Modified Physical, Structural and Optical Properties of Bismuth Silicate Glasses

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Rajesh Parmar ◽  
R. S. Kundu ◽  
R. Punia ◽  
N. Kishore ◽  
P. Aghamkar
Keyword(s):  
Optical Properties ◽  
Silicate Glasses ◽  
Bandgap Energy ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
Scanning Calorimetry ◽  
Bismuth Silicate ◽  
Vis Spectroscopy ◽  
Amorphous Nature ◽  
Optical Bandgap Energy

Iron-containing bismuth silicate glasses with compositions 60SiO2·(100−x)Bi2O3·xFe2O3 have been prepared by conventional melt-quenching technique. The amorphous nature of the glass samples has been ascertained by the X-ray diffraction. The density (d) has been measured using Archimedes principle, molar volume (Vm) has also been estimated, and both are observed to decrease with the increase in iron content. The glass transition temperature (Tg) of these iron bismuth silicate glasses has been determined using differential scanning calorimetry (DSC) technique, and it increases with the increase in Fe2O3 content. The IR spectra of these glasses consist mainly of [BiO6], [BiO3], and [SiO4] structural units. The optical properties are measured using UV-VIS spectroscopy. The optical bandgap energy (Eop) is observed to decrease with the increase in Fe2O3 content, whereas reverse trend is observed for refractive index.

Ternary diagrams of the phase, optical bandgap energy and photoluminescence of mixed-halide perovskites

2019 ◽  
Vol 181 ◽  
pp. 460-469 ◽  
Author(s):  
Se-Yun Kim ◽  
Ho-Chang Lee ◽  
Yujin Nam ◽  
Yeonghun Yun ◽  
Si-Hong Lee ◽  
...  
Keyword(s):  
Optical Bandgap ◽  
Bandgap Energy ◽  
Ternary Diagrams ◽  
Optical Bandgap Energy ◽  
Halide Perovskites

Nitrogen-Doping Induced Optical Bandgap Widening of P-Type Cu2O Flms

2009 ◽  
Vol 1217 ◽  
Author(s):  
Yoshitaka Nakano ◽  
Shu Saeki ◽  
Takeshi Morikawa
Keyword(s):  
Photoelectron Spectroscopy ◽  
Structural Changes ◽  
Optical Bandgap ◽  
Bandgap Energy ◽  
X Ray Diffraction ◽  
X Ray ◽  
N Doping ◽  
Hall Effect Measurements ◽  
Optical Bandgap Energy ◽  
P Type

AbstractWe have investigated the effect of N doping into Cu2O films deposited by reactive magnetron sputtering. With increasing N-doping concentration up to 3 at.%, the optical bandgap energy is enlarged from ˜2.1 to ˜2.5 eV with retaining p-type conductivity as determined by optical absorption and Hall-effect measurements. Additionally, photoelectron spectroscopy in air measurements shows an increase in the valence and conduction band shifts with N doping. These experimental results demonstrate possible optical bandgap widening of p-type N-doped Cu2O films, which is a phenomenon that is probably associated with significant structural changes induced by N doping, as suggested from x-ray diffraction measurements.

Optical Bandgap Energy of Wurtzite In-Rich AlInN Alloys

2003 ◽  
Vol 42 (Part 2, No. 2B) ◽  
pp. L141-L143 ◽  
Author(s):  
Qixin Guo ◽  
Tooru Tanaka ◽  
Mitsuhiro Nishio ◽  
Hiroshi Ogawa
Keyword(s):  
Optical Bandgap ◽  
Bandgap Energy ◽  
Optical Bandgap Energy

scholarly journals Characterization of As-Prepared (PMMA-PVA)/CuO-NPs Hybrid Nanocomposite Thin Films

2021 ◽  
Author(s):  
Ahmad Alsaad ◽  
Ahmad Ahmad ◽  
Abdul Raouf Al Dairy ◽  
Issam A. Qattan ◽  
Shatha Al Fawares ◽  
...  
Keyword(s):  
Thin Films ◽  
Refractive Index ◽  
Optical Bandgap ◽  
Bandgap Energy ◽  
Polymeric Thin Films ◽  
Cuo Nps ◽  
Wide Range ◽  
Nanocomposite Thin Films ◽  
Optical Bandgap Energy

We report the synthesis and characterization of Poly Methyl-Meth-Acrylate (PMMA)/Poly vinylalcohol (PVA) polymeric blend doped with different concentrations of Copper oxide (CuO) nanoparticles (NPs). The (PMMA-PVA)/CuO nanocomposite hybrid thin films (wt. % = 0%, 2%, 4%, 8%, and 16%) of CuO NPs are deposited on glass substrates via dip-coating technique. The transmittance (T%), reflectance (R%), the absorption coefficient (α), the optical constants [refractive index (n), extinction coefficient (k)], optical dielectric functions [ɛ',ɛ''] are investigated and interpreted. Tauc, Urbach, Spitzer-Fan, and Drude models are employed to calculate the optical bandgap energy (Eg) and the optoelectronic parameters of the nanocomposite thin films. The refractive index and optical bandgap energy of of (PMMA-PVA) polymeric thin film are found to be (1.5 to 1.85) and 4.101 eV, respectively. Incorporation of specific concentrations of CuO-NPs in (PMMA-PVA) polymeric thin films leads to a noticeable decrease in the optical bandgap energy and to an increase of the refractive index. Moreover, Fourier Transform Infrared Spectroscopy (FTIR) transmittance spectra are measured and analyzed for undoped and doped polymeric thin films to pinpoint the major vibrational modes in the spectral range (500 and 4000 cm-1), as well as, the nature of network bonding in both systems. Thermal stability of thin films is investigated by performing thermogravimetric analysis (TGA). The TGA thermograms confirm that both doped polymeric thin films are thermally stable at temperatures below 110°C which enables them to be attractive for a wide range of optical and optoelectronic applications. Our results indicate that optical, vibrational and thermal properties of both polymeric thin films can be tuned for specific applications by the appropriate corporation of particular concentrations of CuO-NPs.

Sign in / Sign up

Export Citation Format

Share Document