New Organic Dyes with a Phenanthrenequinone Derivative as the π-Conjugated Bridge for Dye-Sensitized Solar Cells

Abstract

A series of organic dyes based on a phenanthrenequinone derivative have been employed for the first time as a π-conjugated bridge in the molecular design of D-π-A structured organic dyes. Photophysical and electrochemical properties of dyes JH201–JH203 have been systematically investigated. The result shows that dye JH202 exhibits a higher molar extinction coefficient and widened absorption spectrum than dye JH201. Upon replacing the butoxyltriphenylamine electron donor with phenothiazine, a bathochromic shift absorption spectrum for dye JH203 was observed. When applied in dye-sensitized solar cells (DSSCs), the device sensitized by JH203 yields the best photo-to-current conversion efficiency of 6.0% under standard AM 1.5G illumination (100 mW/cm2) with a short-circuit photocurrent density (Jsc) of 11.1 mA/cm2, an open-circuit photovoltage (Voc) of 720 mV, and a fill factor (ff) of 74.9%. The maximum incident photo-to-current conversion efficiency reaches 87% at 460 nm.