First-Principle Calculation of High Absorption-TlGaTe2 for Photovoltaic Application

We use first-principle calculations based on hybrid functional and the Bethe-Salpeter equation method to investigate the electronic and optical properties of dichalcogenide TlGaTe2. Based on theoretical studies, TlGaTe2 has until recently been considered as an indirect band gap material, however; by employing more accurate hybrid functional model, we showed that although TlGaTe2 has an indirect band gap of 1.109 eV, it also exhibits a fundamental direct band gap of 1.129 eV. Our finding was further confirmed by the optical studies on TlGaTe2, which show that the absorption peak is registered at a photon energy of 1.129 eV. It was also shown that TlGaTe2 has high optical absorption peaks in the visible region. Based on phonon and elastic constant calculations, it was shown that TlGaTe2 is dynamically and mechanically stable. Our findings show that TlGaTe2 is a potential candidate for photovoltaic application.

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Properties of Novel Non-Silicon Materials for Photovoltaic Applications: A First-Principle Insight

Materials ◽

10.3390/ma11102006 ◽

2018 ◽

Vol 11 (10) ◽

pp. 2006 ◽

Cited By ~ 3

Author(s):

Murugesan Rasukkannu ◽

Dhayalan Velauthapillai ◽

Federico Bianchini ◽

Ponniah Vajeeston

Keyword(s):

Band Gap ◽

Density Functional ◽

Crystalline Silicon ◽

Visible Region ◽

Initial Population ◽

First Principle ◽

Direct Band Gap ◽

Depth Analysis ◽

Photovoltaic Applications ◽

Direct Band

Due to the low absorption coefficients of crystalline silicon-based solar cells, researchers have focused on non-silicon semiconductors with direct band gaps for the development of novel photovoltaic devices. In this study, we use density functional theory to model the electronic structure of a large database of candidates to identify materials with ideal properties for photovoltaic applications. The first screening is operated at the GGA level to select only materials with a sufficiently small direct band gap. We extracted twenty-seven candidates from an initial population of thousands, exhibiting GGA band gap in the range 0.5–1 eV. More accurate calculations using a hybrid functional were performed on this subset. Based on this, we present a detailed first-principle investigation of the four optimal compounds, namely, TlBiS2, Ba3BiN, Ag2BaS2, and ZrSO. The direct band gap of these materials is between 1.1 and 2.26 eV. In the visible region, the absorption peaks that appear in the optical spectra for these compounds indicate high absorption intensity. Furthermore, we have investigated the structural and mechanical stability of these compounds and calculated electron effective masses. Based on in-depth analysis, we have identified TlBiS2, Ba3BiN, Ag2BaS2, and ZrSO as very promising candidates for photovoltaic applications.

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Electronic structures and optical properties of IV A elements-doped 3C-SiC from density functional calculations

Modern Physics Letters B ◽

10.1142/s021798491850389x ◽

2018 ◽

Vol 32 (32) ◽

pp. 1850389 ◽

Cited By ~ 4

Author(s):

Xuefeng Lu ◽

Tingting Zhao ◽

Xin Guo ◽

Meng Chen ◽

Junqiang Ren ◽

...

Keyword(s):

Optical Properties ◽

Band Gap ◽

Electronic Structures ◽

Density Functional ◽

Visible Region ◽

First Principles Calculation ◽

Charge Difference Density ◽

Direct Band ◽

Density Analysis ◽

Indirect Band Gap

Electronic structures and optical properties of IV A elements (Ge, Sn and Pb)-doped 3C-SiC are investigated by means of the first-principles calculation. The results reveal that the structure of Ge-doped system is more stable with a lower formation energy of 1.249 eV compared with those of Sn- and Pb-doped 3C-SiC systems of 3.360 eV and 5.476 eV, respectively. Doping of the IV A elements can increase the band gap, and there is an obvious transition from an indirect band gap to a direct band gap. Furthermore, charge difference density analysis proves that the covalent order of bonding between the doping atoms and the C atoms is Ge–C [Formula: see text] Sn–C [Formula: see text] Pb–C, which is fully verified by population values. Due to the lower static dielectric constant, the service life of 3C-SiC dramatically improved in production practice. Moreover, the lower reflectivity and absorption peak in the visible region, implying its wide application foreground in photoelectric devices.

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Computational Envision of Structural, Electronic, Mechanical and Thermoelectric Properties of PdXSn (X=Zr, Hf) half Heusler compounds

10.22541/au.164139751.17968957/v1 ◽

2022 ◽

Author(s):

Bindu Rani ◽

Aadil Wani ◽

Utkir Sharopov ◽

Kulwinder Kaur ◽

Shobhna Dhiman

Keyword(s):

Band Gap ◽

Thermoelectric Properties ◽

Lattice Thermal Conductivity ◽

First Principle ◽

Heusler Compounds ◽

Boltzmann Transport ◽

Principle Calculation ◽

First Principle Calculation ◽

Good Thermal Stability ◽

Indirect Band Gap

Half heusler compounds have gained attention due to their excellent properties and good thermal stability. In this paper, using first principle calculation and Boltzmann transport equation, we have investigated structural, electronic, mechanical and thermoelectric properties of PdXSn (X=Zr,Hf) half Heusler materials. These materials are indirect band gap semiconductors with band gap of 0.52 (0.44) for PdZrSn (PdHfSn). Calculations of elastic and phonon characteristics show that both materials are mechanically and dynamically stable. At 300K the magnitude of lattice thermal conductivity observed for PdZrSn is 15.16 W/mK and 9.53 W/mK for PdHfSn. The highest ZT value for PdZrSn and PdHfSn is 0.32 and 0.4 respectively.

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A First-Principle Calculation of the Temperature Dependence of the Indirect Band Gap of Silicon

EPL (Europhysics Letters) ◽

10.1209/0295-5075/10/6/011 ◽

1989 ◽

Vol 10 (6) ◽

pp. 569-574 ◽

Cited By ~ 40

Author(s):

R. D King-Smith ◽

R. J Needs ◽

V Heine ◽

M. J Hodgson

Keyword(s):

Temperature Dependence ◽

Band Gap ◽

First Principle ◽

Principle Calculation ◽

First Principle Calculation ◽

Indirect Band Gap

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Transparent All-Oxide Hybrid NiO:N/TiO2 Heterostructure for Optoelectronic Applications

Electronics ◽

10.3390/electronics10090988 ◽

2021 ◽

Vol 10 (9) ◽

pp. 988

Author(s):

Chrysa Aivalioti ◽

Alexandros Papadakis ◽

Emmanouil Manidakis ◽

Maria Kayambaki ◽

Maria Androulidaki ◽

...

Keyword(s):

Band Gap ◽

Single Phase ◽

Structural Disorder ◽

Energy Band Gap ◽

Nitrogen Doped ◽

Nio Thin Film ◽

Direct Band ◽

Output Characteristics ◽

Indirect Band Gap ◽

P Type

Nickel oxide (NiO) is a p-type oxide and nitrogen is one of the dopants used for modifying its properties. Until now, nitrogen-doped NiO has shown inferior optical and electrical properties than those of pure NiO. In this work, we present nitrogen-doped NiO (NiO:N) thin films with enhanced properties compared to those of the undoped NiO thin film. The NiO:N films were grown at room temperature by sputtering using a plasma containing 50% Ar and 50% (O2 + N2) gases. The undoped NiO film was oxygen-rich, single-phase cubic NiO, having a transmittance of less than 20%. Upon doping with nitrogen, the films became more transparent (around 65%), had a wide direct band gap (up to 3.67 eV) and showed clear evidence of indirect band gap, 2.50–2.72 eV, depending on %(O2-N2) in plasma. The changes in the properties of the films such as structural disorder, energy band gap, Urbach states and resistivity were correlated with the incorporation of nitrogen in their structure. The optimum NiO:N film was used to form a diode with spin-coated, mesoporous on top of a compact, TiO2 film. The hybrid NiO:N/TiO2 heterojunction was transparent showing good output characteristics, as deduced using both I-V and Cheung’s methods, which were further improved upon thermal treatment. Transparent NiO:N films can be realized for all-oxide flexible optoelectronic devices.

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Optical Studies of Poly (N-Carbazole) (PVK) Blending with Polyvinylpyrrolidone (PVP) Using Tauc/Davis-Mott Model

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.652-654.527 ◽

2013 ◽

Vol 652-654 ◽

pp. 527-531 ◽

Cited By ~ 1

Author(s):

A.N. Alias ◽

T.I. Tunku Kudin ◽

Z.M. Zabidi ◽

M.K. Harun ◽

Ab Malik Marwan Ali ◽

...

Keyword(s):

Band Gap ◽

Urbach Energy ◽

Quartz Substrate ◽

Optical Studies ◽

Direct Band Gap ◽

Mott Model ◽

Blended Polymer ◽

Electronic Parameters ◽

Direct Band ◽

Indirect Band Gap

The optical absorption spectra of blended poly (N-carbazole) (PVK) with polyvinylpyrrolidone (PVP) in various compositions are investigated. A doctor blade technique was used to coat the blended polymer on a quartz substrate. The electronic parameters such as absorption edge (Ee), allowed direct band gap (Ed), allowed indirect band gap (Ei), Urbach edge (Eu) and steepness parameter (γ) were calculated using Tauc/Davis-Mott Model. The results reveal that the Ee, Ed and Ei increase with increasing of PVP ratio. There also have variation changing in Urbach energy and steepness parameter.

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Biaxial strain modulated the electronic structure of hydrogenated 2D tetragonal silicene

RSC Advances ◽

10.1039/c9ra08634j ◽

2019 ◽

Vol 9 (72) ◽

pp. 42245-42251

Author(s):

Haoran Tu ◽

Jing Zhang ◽

Zexuan Guo ◽

Chunyan Xu

Keyword(s):

Electronic Structure ◽

Band Gap ◽

Biaxial Strain ◽

Direct Band Gap ◽

Direct Band ◽

Indirect Band Gap

Hydrogenation can open the band gap of 2D tetragonal silicene, α-SiH is semiconductors with a direct band gap of 2.436 eV whereas β-SiH is indirect band gap of 2.286 eV. The band gap of α-SiH, β-SiH and γ-SiH can be modulated via biaxial strain.

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LASER-INDUCED MULTIPHOTON PHOTOCONDUCTIVITY IN DIRECT AND INDIRECT BAND GAP CRYSTALS USING Z-SCAN TECHNIQUE

Modern Physics Letters B ◽

10.1142/s0217984909020874 ◽

2009 ◽

Vol 23 (23) ◽

pp. 2783-2789 ◽

Cited By ~ 1

Author(s):

ARUN GAUR ◽

D. K. SHARMA ◽

K. S. SINGH ◽

NAGESHWAR SINGH

Keyword(s):

Absorption Coefficient ◽

Band Gap ◽

Laser Pulses ◽

Beam Waist ◽

Photon Absorption ◽

Nanosecond Laser ◽

Direct Band Gap ◽

Direct Band ◽

Nanosecond Laser Pulses ◽

Indirect Band Gap

Nanosecond laser pulses have employed the photoconductive Z-scan technique. Photoconductivity traces measured by moving the sample across the laser beam waist were used for measuring two and three-photon absorption processes. The value of the three-photon absorption coefficient β3=9.6×10-10 cm 3/ GW 2 in the case of direct, and 8.96×10-12 cm 3/ GW 2 and 5.0×10-12 cm 3/ GW 2 in the case of indirect band gap crystals have been estimated from a comparison of traces measured by exciting the sample with the first and second harmonics of Nd : YAG laser. The low value of β3 in the case of indirect band gap crystals compared to direct band gap crystals is attributed to phonon-assisted transitions.

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