Highly conjugated electron rich thiophene antennas on phenothiazine and phenoxazine-based sensitizers for dye sensitized solar cells

Abstract Four new organic dyes, coded as CSORG6 , CSORG7 , CSORG8 and CSORG9 , comprising electron rich thiophene derivatives as antennas and cyanoacrylic acid as acceptor, bridged by phenothiazine or phenoxazine were designed and synthesized for dye-sensitized solar cells applications. They were fully characterized with their photophysical, electrochemical properties, density functional theory (DFT), time dependent density DFT (TDDFT) and the light-harvesting properties of the new sensitizers were evaluated with nanocrystalline TiO 2 -based devices. Among the four diheteroanthracene based dyes, phenoxazine ( CSORG7 and CSORG9 ) based devices afforded the best photovoltaic performance ( η ) of 6% under standard AM 1.5G solar irradiation, whereas, N719 showed ( η ) 6.4% under the similar fabrication and evolution conditions.