scholarly journals Effect of Metal Oxides and Graphene Upon The Electronic Properties of Polyvinyl Alcohol

2021 ◽  
Author(s):  
Maroof A. Hegazy ◽  
Hend A. Ezzat ◽  
Ibrahim S. Yahia ◽  
Heba Y. Zahran ◽  
Hanan Elhaes ◽  
...  
Keyword(s):  
Polyvinyl Alcohol ◽  
Metal Oxides ◽  
Band Gap ◽  
Electronic Properties ◽  
Electrostatic Potential ◽  
Molecular Electrostatic Potential ◽  
Graphene Quantum Dots ◽  
Band Gap Energy ◽  
Electrical Characteristics ◽  
Gap Energy

Abstract Nanomaterials improve the physical and electronic characteristics of polymer matrices, allowing the matrices to be used as low cost, easy to handle sensors. Nano ZnO oxide is forming nanocomposite with PVA modified with graphene. Rather than ZnO other metal oxides are assumed to enhance the electronic properties of PVA modified with graphene (G). Accordingly, Density Function Theory (DFT) was used to analyze model molecules of Polyvinyl Alcohol (PVA) that improved with various metal oxides and graphene quantum dots (GQDs). To show the influence of nanomaterials on PVA matrix behavior, HOMO/LUMO molecular orbitals and Molecular Electrostatic Potential (MESP) mapping were calculated. The B3LYPL/LAN2DZ model was used to calculate the band gap energy ∆E, total dipole moment (TDM), and Molecular Electrostatic Potential (MESP). The obtained results indicated that PVA interacted with MgO, led to a significant improvement in the electrical characteristics. The incorporation of GQDs into PVA/MgO resulted in a novel nanocomposite with good electrical characteristics and a band gap energy ∆E of 0.201 eV, which is intended to be used as a humidity sensor.

The effect of edges and shapes on band gap energy in graphene quantum dots

2016 ◽  
Vol 175 (1) ◽  
pp. 211-219 ◽  
Author(s):  
Lanchakorn Kittiratanawasin ◽  
Supa Hannongbua
Keyword(s):  
Quantum Dots ◽  
Band Gap ◽  
Graphene Quantum Dots ◽  
Band Gap Energy ◽  
Gap Energy

Selective Photochemical Dry Etching of Compound Semiconductors: Enhanced Control Through Secondary Electronic Properties

1988 ◽  
Vol 129 ◽  
Author(s):  
Carol I. H. Ashby
Keyword(s):  
Quantum Yield ◽  
Band Gap ◽  
Electronic Properties ◽  
Compound Semiconductors ◽  
Dry Etching ◽  
Band Gap Energy ◽  
Carrier Generation ◽  
Gap Energy ◽  
Free Carriers ◽  
Carrier Recombination

ABSTRACTWhen laser-driven etching of a semiconductor requires direct participation of photogenerated carriers, the etching quantum yield will be sensitive to the electronic properties of a specific semiconductor material. The band-gap energy of the semiconductor determines the minimum photon energy needed for carrier-driven etching since sub-gap photons do not generate free carriers. However, only those free carriers that reach the reacting surface contribute to etching and the ultimate carrier flux to the surface is controlled by more subtle electronic properties than the lowestenergy band gap. For example, the initial depth of carrier generation and the probability of carrier recombination between the point of generation and the surface profoundly influence the etching quantum yield. Appropriate manipulation of process parameters can provide additional reaction control based on such secondary electronic properties. Applications to selective dry etching of GaAs and related materials are discussed here.

Density Functional Theory (DFT) Study: Electronic Properties of Silicene under Uniaxial Strain as H2S Gas Sensor

2016 ◽  
Vol 675-676 ◽  
pp. 15-18 ◽  
Author(s):  
Sasfan Arman Wella ◽  
Irfan Dwi Aditya ◽  
Triati Dewi Kencana Wungu ◽  
Suprijadi
Keyword(s):  
Band Gap ◽  
Electronic Properties ◽  
Density Functional ◽  
Band Gap Energy ◽  
Engineering Strain ◽  
Functional Theory ◽  
First Principle Calculation ◽  
Gap Energy ◽  
Center Configuration ◽  
Structural And Electronic Properties

First principle calculation is performed to investigate structural and electronic properties of strained silicene (silicon analogue of graphene) when absorbing the hydrogen sulfide molecule gas. Two configuration of silicene-H2S system, center and hollow configuration, is checked under 0% (pure), 5%, and 10% uniaxial engineering strain. We report that the silicene-H2S system in center configuration has larger binding energy compare to the silicene-H2S system in hollow configuration. The results show that H2S is physisorbed on silicene. In this work, we also find the change of band gap energy (~60 meV) is appearing when H2S interacted with silicene in center configuration, whereas the band gap energy of silicene has no change when interacted with H2S in hollow configuration.

Illumination Effect on Electrical Characteristics of Poly(3-hexylthiophene-2,5-diyl) Thin-Film Transistors

2020 ◽  
Vol 20 (7) ◽  
pp. 4368-4372
Author(s):  
Hyunji Shin ◽  
Jaehoon Park ◽  
Sungkeun Baang ◽  
Jong Sun Choi
Keyword(s):  
Thin Film ◽  
Band Gap ◽  
Photon Energy ◽  
Thin Film Transistors ◽  
Band Gap Energy ◽  
Light Illumination ◽  
Electrical Characteristics ◽  
Solution Processed ◽  
Gap Energy ◽  
Monochromatic Illumination

We investigate the electrical characteristics of solution-processed poly(3-hexylthiophene-2,5-diyl) (P3HT) thin-film transistors (TFTs) under monochromatic illumination conditions at different wavelengths of 700, 655, 515, and 315 nm. The TFT characteristics measured under light illumination at the wavelengths of 700 and 655 nm were comparable to those measured in the dark state. In addition, light illumination at a wavelength of 515 nm, of which photon energy (~2.4 eV) is higher than the band gap energy of P3HT (~1.7 eV), had a little effect on the electrical characteristics of P3HT TFTs. On the other hand, the TFT performance was notably changed by light illumination at a wavelength of 315 nm. These results indicate that the photon energy, which cause the characteristic degradation in the solution-processed P3HT TFTs, is much higher than the band gap energy of P3HT. Consequently, the illumination-induced variation in the TFT performance can be understood through a broad distribution of energetic states in the solution-processed P3HT semiconductor.

Effect of Blending on the Enhancement of Electronic Properties of Biopolymers

2016 ◽  
Vol 13 (10) ◽  
pp. 6800-6802
Author(s):  
Naziha Suliman Alghunaim
Keyword(s):  
Hydrogen Bonding ◽  
Dipole Moment ◽  
Molecular Modeling ◽  
Band Gap ◽  
Electronic Properties ◽  
Band Gap Energy ◽  
The Other ◽  
Total Dipole Moment ◽  
Gap Energy ◽  
Chitosan Blends

Chitosan (Cs), gelatin (Gel) and starch (Str) are blended together to investigate the effect of blending upon the electronic properties of biopolymers. Three blends namely 25%, 50% and 75% of (Cs/Gel) and (Cs/Str) respectively. FTIR were utilized to ensure the occurrence of the proposed blend. The FTIR spectra show the occurrence of hydrogen bonding which indicated that the assigned blend is formed as a result of hydrogen bonding of NH2 and COOH terminals. Electronic properties are indicated with molecular modeling technique at PM6 semiemperical level. Modeling results indicate that, as far as starch and gelatin ratios increased in chitosan blends, the band gap energy is decreased in one hand while the total dipole moment is increased on the other hand.

scholarly journals Electronic properties of palladium diselenide by density functional theory

2017 ◽  
Vol 13 (3) ◽  
Author(s):  
Ying Xuan Ng ◽  
Rashid Ahmed ◽  
Abdullahi Lawal ◽  
Bakhtiar Ul Haq ◽  
Afiq Radzwan ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Band Gap ◽  
Electronic Properties ◽  
Density Functional ◽  
Band Gap Energy ◽  
Partial Density ◽  
Full Potential ◽  
Functional Theory ◽  
Lattice Constants ◽  
Gap Energy

The knowledge of the structural and electronic properties of a material is important in various applications such as optoelectronics and thermoelectric devices. In this study, we are using full potential linearized augmented plane wave method framed within density functional theory provided by WIEN2k to optimize the structure of PdSe2 in orthorhombic (Pbca) phase and calculate its electronic properties. With the implementation of local density approximation (LDA), Perdew-Burke-Ernzerhof parameterization of generalized gradient approximation (PBE-GGA), Wu-Cohen parameterization of GGA (WC-GGA), and PBE correction for solid GGA (PBEsol-GGA), the computed results of lattice constants are found to be within 5% error with the experiment data. Also, our calculated indirect band gap energy was found to be ~0.24 eV by LDA along with modified Becke-Johnson potential functional (mBJ) with experimental lattice constants and ~0.52 eV by using PBE-GGA with optimized lattice constants. However, the effect of spin-orbit coupling is not found too much on the band gap energy. By analyzing the partial density of states, we identify that d-orbital of Pd is demonstrating a slightly more significant contribution to both the valence and conduction band near to Fermi level which is also in agreement with the previous first principles study.

scholarly journals Crystal-seeds induced construction of ZnO–ZnFe2O4 micro-cubic composites as excellent anode materials for lithium ion battery

RSC Advances ◽  
2018 ◽  
Vol 8 (29) ◽  
pp. 16187-16192 ◽  
Author(s):  
Pei Pan ◽  
Ting Wang ◽  
Lihui Chen ◽  
Feng Wang ◽  
Xiong Yang ◽  
...  
Keyword(s):  
Transition Metal ◽  
Electrochemical Performance ◽  
Metal Oxides ◽  
Band Gap ◽  
Transition Metal Oxides ◽  
Anode Materials ◽  
Lithium Ion ◽  
Band Gap Energy ◽  
Hetero Structure ◽  
Gap Energy

This work aims at designing a fine assembly of two different transition metal oxides with a distinct band-gap energy into a bi-component-active hetero-structure to improve electrochemical performance.

scholarly journals Effect of hydration on the physical properties of glucose

2019 ◽  
Vol 9 (4) ◽  
pp. 4114-4118 ◽  
Keyword(s):  
Quantum Mechanics ◽  
Dipole Moment ◽  
Band Gap ◽  
Electronic Properties ◽  
Band Gap Energy ◽  
Molecular Electrostatic Potentials ◽  
Total Dipole Moment ◽  
Gap Energy ◽  
Homo Lumo ◽  
Electro Negativity

The effect of hydration on the electronic properties of glucose (Gl) is studied by quantum mechanics by using DFT procedures atB3LYP/6-31g(d,p). Total dipole moment, the highest and the lowest occupied molecular orbital (HOMO/LUMO band gap energy) and molecular electrostatic potentials (ESPs) are calculated at the same level of theory for all model molecules. The results indicated that there is an enhancement in the electronic properties of Gl where TDM of Gl is increased from2.5454Debye to 4.3157Debye while HOMO/LUMO band gap energy is decreased from 13.0994 eV to 3.2749 eV. Also, the calculated ESP results are indicated that the electro-negativity is increased due to hydration which means that the reactivity is increased and hence the electronic properties are improved.

Phase Transition and Electronic Properties of LiBH4 via First-Principles Calculations

2014 ◽  
Vol 971-973 ◽  
pp. 119-122
Author(s):  
Hai Ping Wang
Keyword(s):  
Band Gap ◽  
Electronic Properties ◽  
Density Functional ◽  
Density Functional Theory Method ◽  
Band Gap Energy ◽  
First Principles Calculations ◽  
Volume Data ◽  
Functional Theory ◽  
Gap Energy ◽  
Phase Sequence

The transition phase and electronic properties of LiBH4 were investigated by ab initio plane-wave pseudopotential density functional theory method. According to the theoretical calculation, the phase sequence Pnma → P21/c → Cc is obtained. The phase transitions Pnma → P21/c and P21/c → Cc are at the pressure of 1.64 GPa and 2.83 GPa, respectively, by total energy-volume data. As the pressure increases, the value of the band gap energy is reduced from 7.1 (Pnma) to 6.1 eV (Cc). Moreover, the electronic properties of the high pressure phases are discussed. The electronic properties are linked to the band gap energy, total (partly) density of states and atoms (bond) populations.

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