Theoretical study of nitrogen cation modified aromatics containing thiophene as π-linker for p-type photosensitizers

• Published in: Journal of molecular modeling Vol. 25; no. 10; pp. 300 - 14
• Main Authors: Sun, Zhi-Dan, Zhao, Jiang-Shan, Mei, Zheng, Ju, Xue-Hai
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.10.2019; Springer Nature B.V
• Subjects: Adsorption; Anchoring; Cations; Characterization and Evaluation of Materials; Charge transfer; Chemistry; Chemistry and Materials Science; Computer Appl. in Life Sciences; Computer Applications in Chemistry; Density functional theory; Doppler effect; Dye-sensitized solar cells; Dyes; Energy gap; Molecular Medicine; Nitrogen; Optical properties; Original Paper; Performance enhancement; Photovoltaic cells; Red shift; Theoretical and Computational Chemistry; Time dependence; π-Linker; Dyes; DFT; Amine salt; type DSSCs; p-type DSSCs
• ISSN: 1610-2940; 0948-5023; 0948-5023
• DOI: 10.1007/s00894-019-4179-0

On the basis of triphenylamine as an electron donor with attachment of two –COOH anchoring groups and dicyanovinyl as acceptor, ten dyes with D-π-A structures were designed to investigate the effects of different π-linker groups on the properties of the sensitizers, especially the influence of the π-linkers containing nitrogen cation (N + ). The optimized structures and electronic and optical properties were investigated by the density functional theory (DFT) and time-dependent DFT (TD-DFT). The results show that all the investigated dyes can be used as dye sensitizers for the p -type dye-sensitized solar cells (DSSCs) except one dye which contains two N + . The N + modified dye (named S3-PZL1C) has narrow energy gap (2.02 eV), the best light-harvesting efficiency (LHE, 0.9974), and the smallest internal reorganization energy ( λ int  = 7.00 kcal/mol). Importantly, S3-PZL1C displays the largest red shift of the UV-vis absorption, the maximum integral values of the adsorption-wavelength curves over the visible light (400~800 nm), and the strongest adsorption energy (− 66.84 kcal/mol) on NiO surface. In addition, S3-PZL1C not only enhances the electronic excitation but also improves the reorganization energy and charge separation. The intramolecular charge transfer towards the acceptor is sensitive to the N + position in π-linkers. Therefore, the suitable introduction of N + in dyes can improve the performance of the dyes, and the PZL1C moiety may be a promising π-linker for p -type DSSCs. Graphical abstract