Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 Aug 28;24(17):3134.
doi: 10.3390/molecules24173134.

Effect of Nitrogen Cation as "Electron Trap" at π-Linker on Properties for p-Type Photosensitizers: DFT Study

Zhi-Dan Sun  1 , Jiang-Shan Zhao  1 , Xue-Hai Ju  2 , Qi-Ying Xia  3
Affiliations

Effect of Nitrogen Cation as "Electron Trap" at π-Linker on Properties for p-Type Photosensitizers: DFT Study

Zhi-Dan Sun et al. Molecules. .

Abstract

On the basis of thieno(3,2-b)thiophene and dithieno[3,2-b:2',3'-d]thiophene (T2 and T3 moieties) as π-linker, the A, D and S series dyes were designed to investigate the effect of the introducing N+ as an "electron trap" into T2 and T3 on the properties of the dyes. The optimized structures, electronic and optical properties were investigated by the density functional theory (DFT) and time-dependent DFT (TD-DFT). The results show that the properties of the dyes are sensitive to the N+ position in π-linkers. D series dyes with electron-withdrawing units located near the donor have better properties than the corresponding A series with the electron-withdrawing units located near the acceptor. For A and D series, the N+ modified dye named T2N+1-d displays the largest red shift of the UV-vis absorption, the maximum integral values of the adsorption-wavelength curves over the visible light, the highest light harvesting efficiency (LHE, 0.996), and the strongest adsorption energy (-44.33 kcal/mol). T2N+1-d also has a large driving force of hole injection (ΔGinj, -0.74 eV), which results in a more efficient hole injection. Bearing a lengthier π-linker than T2N+1-d, the properties of T2N+1-s are further improved. T2N+1-d moiety or its increased conjugated derivatives may be a promising π-linker.

Keywords: amine salt; density functional theory (DFT); dyes; p-type dye-sensitized solar cells (DSSCs); π-linker.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Molecular structures of the investigated dyes.
Figure 2
Figure 2
Absorption spectra of dyes. Comparison of T1, T2, and D series (a), comparison between D and A series (b), comparison between D and S series (c), and comparison of the selected dyes and T series (d).
Figure 2
Figure 2
Absorption spectra of dyes. Comparison of T1, T2, and D series (a), comparison between D and A series (b), comparison between D and S series (c), and comparison of the selected dyes and T series (d).
Figure 3
Figure 3
The integral area of absorption-wavelength curve over 400~800 nm.
Figure 4
Figure 4
Frontier molecular orbital energy levels and energy gap, together with EVB (NiO) and E(I−/I3−).
Figure 5
Figure 5
The comparison of the simulated UV-vis absorption spectra between RN+/PF6− and the RN+.
Figure 6
Figure 6
Comparison of the frontier molecular orbital energy levels and energy gaps of RN+/PF6− and the RN+.
Figure 7
Figure 7
Adsorption of T2N+1-d on (NiO)10 × 2.
See this image and copyright information in PMC

References

    1. O’Regan B., Grätzel M. A low-cost, high-efficiency solar cell based on dye-sensitized colloidal TiO2 films. Nature. 1991;353:737–740. doi: 10.1038/353737a0. - DOI
    1. Naik P., Rui S., Elmorsy M.R., El-Shafei A., Adhikari A.V. New carbazole based dyes as effective co-sensitizers for DSSCs sensitized with ruthenium (II) complex (NCSU-10) J. Energ. Chem. 2018;27:351–360. doi: 10.1016/j.jechem.2017.12.013. - DOI
    1. Bao L.Q., Ho P., Chitumalla R.K., Jang J., Thogiti S., Kim J.H. Single and double branched organic dyes based on carbazole and red-absorbing cationic indolium for p-type dye-sensitized solar cells: A combined experimental and theoretical investigation. Dye. Pigment. 2018;149:25–36. doi: 10.1016/j.dyepig.2017.09.042. - DOI
    1. Ji Z., Natu G., Huang Z., Wu Y. Linker effect in organic donor–acceptor dyes for p-type NiO dye sensitized solar cells. Energy Environ. Sci. 2011;4:2818–2821. doi: 10.1039/c1ee01527c. - DOI
    1. Zhang F., Yu P., Shen W., Li M., He R. Effect of “push–pull” sensitizers with modified conjugation bridges on the performance of p-type dye-sensitized solar cells. RSC Adv. 2015;5:64378–64386. doi: 10.1039/C5RA09263A. - DOI

MeSH terms