On the Optical Absorption of Thin BaO Film in the Ultraviolet Region

We calculated the energy band structure and the optical absorption and reflectivity for each of the ultrathin 2D hexagonal materials MoS2, MoP2, NbS2, and NbP2. Our simulations included density functional theory, generalized gradient approximation (GGA), and the Quantum Espresso code. Other researchers already synthesized the first three materials. We obtained that NbP2 should be another hexagonal 2D material. In all cases in the infrared and visible ranges, the absorptions present much larger concerning graphene. However, the absorptions for MoP2, NbP2, and NbS2, are far more prominent concerning MoS2. In the ultraviolet region, the absorptions are like each other and differ from graphene. In all cases, the reflectivities are similar to each other and vary from graphene.

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Electronic structure and optical absorption of the Bi4Ge3O12 and the Bi4Si3O12 scintillators in ultraviolet region: An ab initio study

Journal of Applied Physics ◽

10.1063/1.3160291 ◽

2009 ◽

Vol 106 (1) ◽

pp. 013715 ◽

Cited By ~ 24

Author(s):

A. F. Lima ◽

S. O. Souza ◽

M. V. Lalić

Keyword(s):

Electronic Structure ◽

Optical Absorption ◽

Ab Initio ◽

Ultraviolet Region ◽

Ab Initio Study

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Optical Properties and Conductivity of PVA–H3PO4 (Polyvinyl Alcohol–Phosphoric Acid) Film Blend Irradiated by γ-Rays

Polymers ◽

10.3390/polym13071065 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1065

Author(s):

Susilawati Susilawati ◽

Saiful Prayogi ◽

Muhamad F. Arif ◽

Noor Maizura Ismail ◽

Muhammad Roil Bilad ◽

...

Keyword(s):

Optical Properties ◽

Radiation Dose ◽

Optical Absorption ◽

Phosphoric Acid ◽

Polyvinyl Alcohol ◽

Polymer Film ◽

Energy Gap ◽

Visible Region ◽

Ultraviolet Region ◽

Γ Rays

This study assesses the optical properties and conductivity of PVA–H3PO4 (polyvinyl alcohol–phosphoric acid) polymer film blend irradiated by gamma (γ) rays. The PVA–H3PO4 polymer film blend was prepared by the solvent-casting method at H3PO4 concentrations of 75 v% and 85 v%, and then irradiated up to 25 kGy using γ-rays from the Cobalt-60 isotope source. The optical absorption spectrum was measured using an ultraviolet–visible spectrophotometer over a wavelength range of 200 to 700 nm. It was found that the absorption peaks are in three regions, namely two peaks in the ultraviolet region (310 and 350 nm) and one peak in the visible region (550 nm). The presence of an absorption peak after being exposed to hυ energy indicates a transition of electrons from HOMO to LUMO within the polymer chain. The study of optical absorption shows that the energy band gap (energy gap) depends on the radiation dose and the concentration of H3PO4 in the polymer film blend. The optical absorption, absorption edge, and energy gap decrease with increasing H3PO4 concentration and radiation dose. The interaction between PVA and H3PO4 blend led to an increase in the conductivity of the resulting polymer blend film.

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