Band gap determination by absorption spectrum fitting method (ASF) and structural properties of different compositions of (60−x) V2O5–40TeO2–xSb2O3 glasses

2009 ◽  
Vol 355 (31-33) ◽  
pp. 1597-1601 ◽  
Author(s):  
Dariush Souri ◽  
Kobra Shomalian
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ateyyah M. Al-Baradi ◽  
Ahmed A. Atta ◽  
Ali Badawi ◽  
Saud A. Algarni ◽  
Abdulraheem S. A. Almalki ◽  
...  

Abstract In the current work, the optical properties of tin oxide thin films have been tailored via gamma irradiation for energy applications. The effect of Gamma radiation (50, 100, 150, 200 and 250 kGy) on the microstructural, absorption and oscillator parameters of SnO2 thin films has been investigated. XRD results reveal that the SnO2 films have the symmetry of the space group P42/mnm belonging to the tetragonal system. The crystallite size of γ-irradiated SnO2 thin film slightly increases as the irradiation dose increases. The allowed optical band gaps are estimated by applying various methods such as Tauc’s method, derivation of absorption spectrum fitting and absorption spectrum fitting approaches. The dispersion parameters are extracted from the dispersion curve of the real part of the refractive index. The single-effective-oscillator and Drude models for free charge carrier absorption are applied to obtain the dispersion parameters before and after γ-irradiation.


Author(s):  
Julia Wiktor ◽  
Igor Reshetnyak ◽  
Francesco Ambrosio ◽  
Alfredo Pasquarello

ChemInform ◽  
2014 ◽  
Vol 45 (40) ◽  
pp. no-no
Author(s):  
Feng Hao ◽  
Constantinos C. Stoumpos ◽  
Robert P. H. Chang ◽  
Mercouri G. Kanatzidis

2020 ◽  
Vol 34 (17) ◽  
pp. 2050147
Author(s):  
Yuqin Guan ◽  
Qingyu Hou ◽  
Danyang Xia

The effect of intrinsic point defects on the electronic structure and absorption spectra of ZnO was investigated by first-principle calculation. Among the intrinsic point defects in ZnO, oxygen vacancies [Formula: see text] and interstitial zinc [Formula: see text] have the lower formation energy and the more stable structure under zinc(Zn)-rich condition, whereas zinc vacancies [Formula: see text] and interstitial oxygen [Formula: see text] have the lower formation energy and the more stable structure under oxygen(O)-rich condition. The band gap of [Formula: see text] becomes narrow and the absorption spectrum has a redshift. In the visible region, the photo-excited electron transition of [Formula: see text] is graded from the valence band top to the impurity level and then to the conduction band bottom, showing the redshift of absorption spectrum of [Formula: see text] and explaining the reason of [Formula: see text] forming a deep impurity levels in ZnO. Moreover, the impurity energy level of [Formula: see text] coincides with the Fermi level, indicating the significant trap effect and the slow recombination of electrons and holes, which are conducive to the design and preparation of novel ZnO photocatalysts. The band gap of [Formula: see text] and [Formula: see text] broadened and the absorption spectrum showed blueshift, explaining the different values of the ZnO band gap width.


2007 ◽  
Vol 102 (11) ◽  
pp. 113108 ◽  
Author(s):  
Yingxin Wang ◽  
Ziran Zhao ◽  
Zhiqiang Chen ◽  
Kejun Kang ◽  
Bing Feng ◽  
...  

2020 ◽  
Vol 22 (21) ◽  
pp. 11936-11942
Author(s):  
Kangli Wang ◽  
Beate Paulus

Using the DFT-GW-BSE method, we analyze how the electronic band gap, optical absorption spectrum and exciton binding energy of the MoS2 monolayer are influenced by NO and C3H3N3 molecules and S-defects.


Sign in / Sign up

Export Citation Format

Share Document