Acenaphthylene-Based Chromophores for Dye-Sensitized Solar Cells: Synthesis, Spectroscopic Properties, and Theoretical Calculations

Gabriela Malta; João Pina; J Carlos Lima; A Jorge Parola; Paula S Branco

doi:10.1021/acsomega.4c01201

Acenaphthylene-Based Chromophores for Dye-Sensitized Solar Cells: Synthesis, Spectroscopic Properties, and Theoretical Calculations

ACS Omega. 2024 Mar 15;9(12):14627-14637. doi: 10.1021/acsomega.4c01201. eCollection 2024 Mar 26.

Authors

Gabriela Malta¹, João Pina², J Carlos Lima¹, A Jorge Parola¹, Paula S Branco¹

Affiliations

¹ LAQV@REQUIMTE, Chemistry Department of Nova School of Science and Technology, Nova University of Lisbon, Campus de Caparica, Caparica 2829-516, Portugal.
² CQC-IMS, Department of Chemistry, University of Coimbra, Rua Larga, Coimbra 3004-535, Portugal.

Abstract

A set of acenaphthylene dyes with arylethynyl π-bridges was tested for dye-sensitized solar cells (DSSCs). Crucial steps for the extension of the conjugated system from the acenaphylene core involved Sonogashira coupling reactions. Phenyl, thiophene, benzotriazole, and thieno-[3,2-b]thiophene moieties were employed to extend the conjugation of the π-bridges. The systems were characterized by cyclic voltammetry and by UV-vis absorption and emission. The spectroscopic characterization showed that the last three bridges resulted in red-shifted absorption and emission spectra relative to the parent phenyl-bridged compound, in accordance with TD-DFT calculations. The phenylethynyl derivative 6a achieved a conversion efficiency of 2.51% with V_oc, J_sc, and FF values of 0.365 V, 13.32 mA/cm², and 0.52, respectively. The efficiency of this compound improved to 3.15% with the addition of CDCA (10 mM), representing the best efficiency result in this study. The overall conversion efficiency of the other aryl derivatives 6b-d proved to be significantly inferior (14-40%) to that of 6a due to a significant decrease of J_sc.