Three-component one-pot reaction for molecular engineering of novel cost-effective highly rigid quinoxaline-based photosensitizers for highly efficient DSSCs application: Remarkable photovoltage

Abstract

A simple three-component one-pot approach was developed to generate three novel highly rigid quinoxaline-based dyes, which were further investigated as sensitizers of dye-sensitized solar cells (DSSCs). The effect of different push-pull molecular motifs containing various donors and attachment of long alkyl chains on photophysical, electrochemical and photovoltaic performances, along with theoretical calculations were studied comprehensively. In particular, LY03-based DSSCs showed the highest efficiency of 7.04% with a short-circuit photocurrent density (JSC) of 14.32 mA cm−2, an open-circuit photovoltage (VOC) of 910 mV and a fill factor (FF) of 0.54% under AM 1.5 irradiation (100 mW cm−2). The results confirm that improving the molecular rigidity of sensitizer and incorporation of long alkyl chains into an auxiliary acceptor and donor is one of the most effective pathways to prevent “trade-off” effect, which translated into remarkable improvement in open-circuit photovoltage of 0.91 V, hence, enhancing the photovoltaic performance.