Work

Engineering High-Performance Carbazole-Based Co-Sensitizers: Synthesis, Photophysical Characterization, and Synergistic Enhancement in Dye-Sensitized Solar Cells

Year: 2025

Type: article

Abstract: The current research implies the synthesis of two novel organic co-sensitizers based on carbazole, which are referred to as MA-1 and MA-2 . The performances of these sensitizers in dye-sensitized solar cells (DSSCs) were also studied. The molecular structures were designed using donor-π-acceptor (D-π-A) configurations, where 9-heptyl carbazole and 9-ethyl carbazole served as donors and malononitrile ( MA-1 ) and cyanoacetic acid ( MA-2 ) acted as acceptor/anchoring groups. The photophysical features of the sensitizers were evaluated via UV-Vis spectroscopy, revealing broad absorption in the visible range with λ max at 468 nm ( MA-1 ) and 478 nm ( MA-2 ) and corresponding molar extinction coefficients of 3.76 × 10⁴ M⁻¹cm⁻¹ and 5.34 × 10⁴ M⁻¹cm⁻¹, respectively. Electrochemical analysis showed favorable ground state oxidation potentials (GSOP) and excited state oxidation potentials (ESOP) for both dyes, with optical band gaps of 2.44 eV ( MA-1 ) and 2.28 eV ( MA-2 ). These values indicate efficient electron injection into the TiO 2 conduction band and thermodynamic feasibility for dye regeneration. Co-sensitization using the benchmark N3 dye significantly enhanced the photovoltaic performance. The ( MA-2 + N3 ) achieved the highest power conversion efficiency ( PCE ) of 9.82%, with a short-circuit current density ( J SC ) of 23.91 mA/cm², an open-circuit voltage ( V OC ) of 685 mV, and a fill factor ( FF ) of 0.60. This superior performance can be attributed to the synergistic interactions between the dyes, broader spectral coverage, and improved charge separation dynamics. By utilizing synergistic co-sensitization strategies, these findings shed light on the capacity of carbazole-based co-sensitizers, particularly MA-2 , as potential candidates for high-efficiency DSSCs.

Source: Journal of Fluorescence

DOI: 10.1007/s10895-025-04194-1

Authors: Mariam Eltoukhi, Safa A. Badawy, Ahmed A. Fadda, Ehab Abdel-Latif, Mohamed R. Elmorsy

Institutions: Mansoura University, New Mansoura University

Language: English

Topic: TiO2 Photocatalysis and Solar Cells

Subfield: Renewable Energy, Sustainability and the Environment

Field: Energy

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: hybrid

Estimated APC paid: $4,690