scholarly journals Density Functional Theory Study on the Electronic Structures of Oxadiazole Based Dyes as Photosensitizer for Dye Sensitized Solar Cells

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Umer Mehmood ◽  
Ibnelwaleed A. Hussein ◽  
Khalil Harrabi ◽  
Shakeel Ahmed
Keyword(s):  
Density Functional Theory ◽  
Absorption Spectra ◽  
Density Functional ◽  
Energy Levels ◽  
Dye Sensitized Solar Cells ◽  
Electron Injection ◽  
Molecular Structures ◽  
Visible Absorption ◽  
Functional Theory ◽  
Oxidation Potentials

The molecular structures and UV-visible absorption spectra of complex photosensitizers comprising oxadiazole isomers as theπ-bridges were analyzed by density functional theory (DFT) and time-dependent DFT. The ground state and excited state oxidation potentials, HOMOs and LUMOs energy levels, and electron injection from the dyes to semiconductor TiO2have been computed in vacuum here. The results show that all of the dyes may potentially be good photosensitizers in DSSC. To justify the simulation basis, N3 dye was also simulated under the similar conditions. Simulated absorption spectrum, HOMO, LUMO, and band gap values of N3 were compared with the experimental values. We also computed the electronic structure properties and absorption spectra of dye/(TiO2)8systems to elucidate the electron injection efficiency at the interface. This work is expected to give proper orientation for experimental synthesis.

Influence of Electron Injection Rate in Triphenylamine Based Dye for Dye-Sensitized Solar Cells: A First Principle Study

2019 ◽  
Vol 233 (9) ◽  
pp. 1247-1259
Author(s):  
Madhu Prakasam
Keyword(s):  
Solar Cells ◽  
Absorption Spectra ◽  
Density Functional ◽  
Dye Sensitized Solar Cells ◽  
Visible Region ◽  
Electron Injection ◽  
Injection Rate ◽  
Visible Absorption ◽  
Dye Sensitized ◽  
Sensitized Solar Cells

Abstract In this work, we systematically investigate the impacts of electron-donor based on Triphenylamine (TPA). The Geometry structure, energy levels, light-harvesting ability and ultraviolet-visible absorption spectra were calculated by using Density Functional Theory (DFT) and Time-Dependent-DFT. The electron injection rate of the TPA-N(CH3)2 based dyes has 0.71 eV for high among the dye sensitizer. The First and Second order Hyperpolarizability of the 11.95 × 10−30 e.s.u and 12195.54 a.u, respectively for TPA-N(CH3)2 based dye. The calculated absorption spectra were showed in the ultra-violet visible region for power conversion region. The study reveals that the electron transfer character of TPA-N(CH3)2 based dyes can be made suitable for applications in Dye-Sensitized Solar Cells.

scholarly journals Electronic structures and photovoltaic properties of a novel phthalocyanine and titanium dioxide phthalocyanine for dye sensitized-solar cells

2021 ◽  
Vol 6 (3) ◽  
pp. 107-115
Author(s):  
Fares A. Yasseen ◽  
Faeq A. Al-Temimei
Keyword(s):  
Density Functional Theory ◽  
Solar Cells ◽  
Electronic Structures ◽  
Density Functional ◽  
Energy Gap ◽  
Dye Sensitized Solar Cells ◽  
Solar Spectrum ◽  
Electron Injection ◽  
Basis Set ◽  
Functional Theory

In the present work, geometries, electronic structures, photovoltaic and optical properties have been carried out on a series of structures formation of phthalocyanine and Titanylphthalocyanine dyes, which are replaced by several subgroup. A density functional theory (DFT) approach together with hybrid function (B3LYP) at SDD basis set was used for the ground state properties in the gas phase. The time-dependent density functional theory (TD-DFT)/ B3LYP was used to investigate the excitation properties of new dyes and analyzed the trends in their optical and redox characteristics. Theoretical principles of HOMO and LUMO energy levels of dyes is requisite in analyzing organic solar cells, thus, HOMO, LUMO levels, open circuit voltage, energy gap, light harvestings efficiency, electron regeneration and electron injection have been calculated and discussed. The outcome of the efficiency, the considered dyes explain absorption energy and wavelength properties that correspond to the solar spectrum requirements. According to results, all the considered materials have a good property and possibility of electron injection procedure from the dyes to conduction band of TiO2, PC60BM or PC60BM. As a result, the molecular changes affect the electronic properties of dye molecules for solar cells. Also, a study of new dyes sensitizers showed that designed materials will be excellent sensitizers. Theoretical designing will prae a way for experimentalists to synthesize the efficient sensitizers for solar cells clearer.

Role of heteroatoms and substituents on the structure, reactivity, aromaticity, and absorption spectra of pyrene: a density functional theory study

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Bapan Saha ◽  
Pradip Kumar Bhattacharyya
Keyword(s):  
Density Functional Theory ◽  
Absorption Spectra ◽  
Density Functional ◽  
Structural Parameters ◽  
Visible Absorption ◽  
Functional Theory ◽  
Solvent Phase ◽  
Visible Spectra ◽  
Td Dft ◽  
Uv Visible

Abstract Effect of heteroatoms viz. BN and substituents viz. –Me (methyl), –OH (hydroxyl), –NH2 (amine), –COOH (carboxyl), and –CN (cyano) on the structural parameters, global reactivity, aromaticity, and UV-visible spectra of pyrene are studied with the help of density functional theory (DFT). Global reactivity parameters such as global hardness (η) and electrophilicity (ω) are calculated using density functional reactivity theory (DFRT). Time dependent density functional theory (TD-DFT) is explored for interpreting the UV-visible absorption spectra. Aromaticity of the pyrene rings are predicted from the nucleus independent chemical shift (NICS) values. Presence of BN unit and substituent induces reasonable impact on the studied parameters. The observed absorption spectra lie predominantly within the UV-region (both blue and red shifts are observed in presence of BN and substituent). HOMO energy and absorption spectra are affected nominally in solvent phase.

STRUCTURES AND SPECTROSCOPIC PROPERTIES OF THREE AROMATIC HETEROCYCLIC DYE PHOTOSENSITIZERS

2013 ◽  
Vol 12 (06) ◽  
pp. 1350055
Author(s):  
YUANZUO LI ◽  
CHAOFAN SUN ◽  
LINPO YANG
Keyword(s):  
Density Functional Theory ◽  
Absorption Spectra ◽  
Density Functional ◽  
Energy Levels ◽  
Electron Transition ◽  
Spectroscopic Properties ◽  
Molecular Orbitals ◽  
Functional Theory ◽  
Solvent Phase ◽  
Charge Difference Density

The ground-state structures and absorption spectra of three dyes, carbazole, phenothiazine and diphenylamine, were studied by the density functional theory (DFT) and time-dependent density functional theory (TD-DFT). The strong absorption peak, electron transition as well as the energy levels of molecular orbitals were obtained and compared in the gas and solvent phase. Furthermore, we further calculated the effect of the expanding conjugated bridge on the absorption spectra and the energy levels of molecular orbitals. Visualized method of charge difference density (CDD) was used to show the direction of charge transfer in the molecules of interest during photo-excitation.

scholarly journals Optical Absorption and Electron Injection of 4-(Cyanomethyl)benzoic Acid Based Dyes: A DFT Study

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Yuehua Zhang ◽  
Penghui Ren ◽  
Yuanzuo Li ◽  
Runzhou Su ◽  
Meiyu Zhao
Keyword(s):  
Density Functional Theory ◽  
Benzoic Acid ◽  
Density Functional ◽  
Photovoltaic Performance ◽  
Dye Sensitized Solar Cells ◽  
Electron Injection ◽  
Oxidation Potential ◽  
Conduction Band Edge ◽  
Functional Theory ◽  
Sensitized Solar Cells

Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations were carried out to study the ground state geometries, electronic structures, and absorption spectra of 4-(cyanomethyl)benzoic acid based dyes (AG1 and AG2) used for dye-sensitized solar cells (DSSCs). The excited states properties and the thermodynamical parameters of electron injection were studied. The results showed that (a) two dyes have uncoplanar structures along the donor unit and conjugated bridge space, (b) two sensitizers exhibited intense absorption in the UV-Vis region, and (c) the excited state oxidation potential was higher than the conduction band edge of TiO2photoanode. As a result, a solar cell based on the 4-(cyanomethyl)benzoic acid based dyes exhibited well photovoltaic performance. Furthermore, nine dyes were designed on the basis of AG1 and AG2 to improve optical response and electron injection.

scholarly journals Molecular Structures and Spectral Properties of Natural Indigo and Indirubin: Experimental and DFT Studies

Molecules ◽  
2019 ◽  
Vol 24 (21) ◽  
pp. 3831 ◽  
Author(s):  
Zixin Ju ◽  
Jie Sun ◽  
Yanping Liu
Keyword(s):  
Density Functional Theory ◽  
Spectral Properties ◽  
Density Functional ◽  
Dft Method ◽  
Molecular Structures ◽  
Basis Set ◽  
Frontier Molecular Orbital ◽  
Visible Absorption ◽  
Functional Theory ◽  
Uv Visible

This paper presents a comparative study on natural indigo and indirubin in terms of molecular structures and spectral properties by using both computational and experimental methods. The spectral properties were analyzed with Fourier transform infrared (FTIR), Raman, UV-Visible, and fluorescence techniques. The density functional theory (DFT) method with B3LYP using 6-311G(d,p) basis set was utilized to obtain their optimized geometric structures and calculate the molecular electrostatic potential, frontier molecular orbitals, FTIR, and Raman spectra. The single-excitation configuration interaction (CIS), time-dependent density functional theory (TD-DFT), and polarization continuum model (PCM) were used to optimize the excited state structure and calculate the UV-Visible absorption and fluorescence spectra of the two molecules at B3LYP/6-311G(d,p) level. The results showed that all computational spectra agreed well with the experimental results. It was found that the same vibrational mode presents a lower frequency in indigo than that in indirubin. The frontier molecular orbital analysis demonstrated that the UV-Visible absorption and fluorescence bands of indigo and indirubin are mainly derived from π → π* transition. The results also implied that the indigo molecule is more conjugated and planar than indirubin, thereby exhibiting a longer maximum absorption wavelength and stronger fluorescence peak.

Modelling the visible absorption spectra of copper(II) acetylacetonate by Density Functional Theory

2010 ◽  
Vol 492 (1-3) ◽  
pp. 14-18 ◽  
Author(s):  
K.J. de Almeida ◽  
A. Cesar ◽  
Z. Rinkevicius ◽  
O. Vahtras ◽  
Hans Ågren
Keyword(s):  
Density Functional Theory ◽  
Absorption Spectra ◽  
Density Functional ◽  
Visible Absorption ◽  
Functional Theory
Sign in / Sign up

Export Citation Format

Share Document