Theoretical design of push-pull porphyrin dyes with π-bridge modification for dye-sensitized solar cells

A series of new D-pi-A porphyrin-based dyes,based on GY50 by utilizing 2-cyanoacrylic acid anchoring group and modifying the pi bridge with thiophene, furan and/or vinyl groups, has been designed and investigated for screening efficient sensitizers in dye sensitized solar cells (DSSCs). The efficiency of the designed dye molecules is analyzed through various parameters. The absorption spectra of the designed dyes exhibit the dual Soret and Q bands as that of GY50 with increased molar extinction coefficients as well as red-shifted peaks for the Qband, and also present a modest hump between the Soret and Qbands (500-600 nm), yielding enhanced light harvesting efficiency. In terms of the absorption spectra together with the charge transfer characteristics, driving force for electron injection, dye regeneration as well as conduction band energy shift, the new sensitizers, especially with bithiophene and bithiophene plus vinyl on the pi bridge, are found to be promising candidates for high-efficiency DSSCs. (C) 2016 Elsevier B.V. All rights reserved.