Exploring the potential of heterocyclic carbazole-derived dyes for DSSCs

Abstract

This study presents the design and synthesis of two novel donor–acceptor (D–A) type heterocyclic carbazole-derived organic dyes, CzP-BA and CzP-TBA, incorporating 9-(p-tolyl)-9H-carbazole as the electron donor and barbituric acid or thiobarbituric acid as electron acceptors. These dyes were developed with a strategic molecular framework to support optoelectronic applications, especially in dye-sensitized solar cells (DSSCs). Comprehensive characterization of their optical, thermal, and theoretical properties was conducted to understand their suitability in optoelectronic applications. The linkage of carbazole to barbituric acid or thiobarbituric acid enhances light absorption, as indicated by absorption peaks at 447 nm for CzP-BA and 474 nm for CzP-TBA. Electrochemical studies reveal that both dyes possess the necessary thermodynamic driving forces to function effectively as photosensitizers in DSSCs. Furthermore, DFT and MESP calculations provide insight into their electronic structures, highlighting their potential as effective photosensitizers. Together, these results showcase CzP-BA and CzP-TBA as promising candidates for practical use in optoelectronic systems.