New D-π-A-conjugated organic sensitizers based on α-pyranylidene donors for dye-sensitized solar cells

A series of new push-pull organic dyes incorporating a cyanoacrylic acid group as electron acceptor unit and alpha-chalcogenopyranylidene group (X = S; 0) as electron donor unit has been synthesized, characterized and used as sensitizer for dye-sensitized solar cells (DSSCs). For the first time, alpha-pyranylidene and thiopyranylidene groups, have been evaluated in DSSC. To obtain the thermodynamic values of the solar cell, an investigation of their electrochemical (CV) and optical properties (UV-vis absorption spectroscopy) is also reported. (C) 2017 Elsevier Ltd. All rights reserved.