Theoretical study of novel D-A-π-A-π-A conjugated organic dye sensitizers : impact of alkyl chain and electron-withdrawing functional groups substitution
(2025) In Solar Energy 297.- Abstract
The influence of alkyl chain on the physical and photochemical properties of D-A-π-A-π-A sensitizers (GZ-121 and GZ-124) for dye-sensitized solar cells (DSSCs) was investigated through density functional theory (DFT). Key aspects examined include geometry, optical characteristic, electron injection, intramolecular charge transfer, and dye regeneration. Adsorption models of dye@TiO2, short-circuit current density (Jsc), open circuit voltage (Voc), and photoelectric conversion efficiency (PCE) were also analyzed. The presence of the alkyl chain in GZ-121 inhibits molecular distortion, promotes the separation of holes and electrons, and extends the excited state lifetime, facilitating electron injection.... (More)
The influence of alkyl chain on the physical and photochemical properties of D-A-π-A-π-A sensitizers (GZ-121 and GZ-124) for dye-sensitized solar cells (DSSCs) was investigated through density functional theory (DFT). Key aspects examined include geometry, optical characteristic, electron injection, intramolecular charge transfer, and dye regeneration. Adsorption models of dye@TiO2, short-circuit current density (Jsc), open circuit voltage (Voc), and photoelectric conversion efficiency (PCE) were also analyzed. The presence of the alkyl chain in GZ-121 inhibits molecular distortion, promotes the separation of holes and electrons, and extends the excited state lifetime, facilitating electron injection. GZ-124 exhibits a faster charge transfer rate due to lower reorganization energy, with electrochemical parameters indicating superior electron transport capacity and stability. The narrower energy gap results in a more red-shifted absorption spectrum and wider spectral response range, thereby enhancing the light harvesting efficiency. Consequently, GZ-124 exhibited a higher Jsc of 19.77 mA cm−2 and a PCE of 12.92 %. Additionally, molecular design involved substituting furan and thiophene at different π-bridge positions to investigate the impact of electron-rich functional group substitution on the photoelectric properties of DSSCs. Compared to the original molecule, the modified designs exhibit higher Jsc and PCE values. Theoretical simulation results demonstrate the feasibility of substituting electron-withdrawing functional groups to enhance photovoltaic performance, thereby providing valuable guidance for the design of photosensitizers with dual auxiliary acceptors.
(Less)
- author
- Li, Jingping ; Guo, Huijie ; Zhong, Yanan ; Pullerits, Tõnu LU and Song, Peng
- organization
- publishing date
- 2025-09
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Density functional theory, Dye-sensitized solar cell, Molecular design, Sensitizers
- in
- Solar Energy
- volume
- 297
- article number
- 113621
- publisher
- Elsevier
- external identifiers
-
- scopus:105005766689
- ISSN
- 0038-092X
- DOI
- 10.1016/j.solener.2025.113621
- language
- English
- LU publication?
- yes
- id
- cf3133e3-de19-42b3-b45f-2a5e3da12dc4
- date added to LUP
- 2025-07-18 09:39:11
- date last changed
- 2025-07-18 09:40:04
@article{cf3133e3-de19-42b3-b45f-2a5e3da12dc4,
abstract = {{<p>The influence of alkyl chain on the physical and photochemical properties of D-A-π-A-π-A sensitizers (GZ-121 and GZ-124) for dye-sensitized solar cells (DSSCs) was investigated through density functional theory (DFT). Key aspects examined include geometry, optical characteristic, electron injection, intramolecular charge transfer, and dye regeneration. Adsorption models of dye@TiO<sub>2</sub>, short-circuit current density (J<sub>sc</sub>), open circuit voltage (V<sub>oc</sub>), and photoelectric conversion efficiency (PCE) were also analyzed. The presence of the alkyl chain in GZ-121 inhibits molecular distortion, promotes the separation of holes and electrons, and extends the excited state lifetime, facilitating electron injection. GZ-124 exhibits a faster charge transfer rate due to lower reorganization energy, with electrochemical parameters indicating superior electron transport capacity and stability. The narrower energy gap results in a more red-shifted absorption spectrum and wider spectral response range, thereby enhancing the light harvesting efficiency. Consequently, GZ-124 exhibited a higher J<sub>sc</sub> of 19.77 mA cm<sup>−2</sup> and a PCE of 12.92 %. Additionally, molecular design involved substituting furan and thiophene at different π-bridge positions to investigate the impact of electron-rich functional group substitution on the photoelectric properties of DSSCs. Compared to the original molecule, the modified designs exhibit higher J<sub>sc</sub> and PCE values. Theoretical simulation results demonstrate the feasibility of substituting electron-withdrawing functional groups to enhance photovoltaic performance, thereby providing valuable guidance for the design of photosensitizers with dual auxiliary acceptors.</p>}},
author = {{Li, Jingping and Guo, Huijie and Zhong, Yanan and Pullerits, Tõnu and Song, Peng}},
issn = {{0038-092X}},
keywords = {{Density functional theory; Dye-sensitized solar cell; Molecular design; Sensitizers}},
language = {{eng}},
publisher = {{Elsevier}},
series = {{Solar Energy}},
title = {{Theoretical study of novel D-A-π-A-π-A conjugated organic dye sensitizers : impact of alkyl chain and electron-withdrawing functional groups substitution}},
url = {{http://dx.doi.org/10.1016/j.solener.2025.113621}},
doi = {{10.1016/j.solener.2025.113621}},
volume = {{297}},
year = {{2025}},
}