Abstract
Complex organic compounds with benzene/thiophene as pi-segments are inspected as photosensitizers for applications in dye sensitized solar cells. To better understand the charge transport process involved in the dye sensitized solar cells, we used the results of Kohn-Sham density functional theory and time-dependent density functional theory (DFT) studies of benzene/thiophene based sensitizers as well as the dye bound to a TiO2 nano cluster. We investigated the electronic structures and UV-Vis spectra of the sensitizers alone and linked to the cluster. We also showed energy level diagrams, the major transitions of molecular orbitals and free energy calculation of the electron transfer from the sensitizer to the conduction band of the TiO2. The results show that LUMO of the dyes is greater than the conduction band of TiO2 indicating that a full charge transfer from dyes to the conduction band of TiO2 is thermodynamically allowed. The calculated results also indicate that D3 is the most plausible sensitizer due to the most negative ΔGinject (0.91 eV) and a larger LHE value (0.95), which results in a higher IPCE.
Original language | English |
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Pages (from-to) | 152-158 |
Number of pages | 7 |
Journal | Dyes and Pigments |
Volume | 118 |
DOIs | |
State | Published - Jul 2015 |
Bibliographical note
Funding Information:The authors would like to acknowledge the support provided by King Abdulaziz City for Science and Technology (KACST) through the Science & Technology Unit at King Fahd University of Petroleum & Minerals (KFUPM) for funding this work through the project # 11-ENE1635-04 as part of National Science, Technology and Innovation Plan. KFUPM is also acknowledged for supporting this research. The authors would like to acknowledge the Center of Research Excellence for Renewable Energy at KFUPM for its support.
Publisher Copyright:
© 2015 Elsevier Ltd. All rights reserved.
Keywords
- Benzene/thiophene
- Density functional theory
- Free energy
- Light harvesting efficiency
- Photosensitizers
- TiO nano cluster
ASJC Scopus subject areas
- Chemical Engineering (all)
- Process Chemistry and Technology