View article

Different from traditional D−π–A sensitizers (the traditional design concept of the organic dyes is the donor−π-linker–acceptor structure), a series of organic dyes with pyridinium as acceptor have been synthesized in order to approach the optimal energy level composition in the TiO₂–dye–iodide/triiodide system in the dye-sensitized solar cells. HOMO and LUMO energy level tuning is achieved by varying the conjugation units and the donating ability of the donor part. Detailed investigation on the relationship between the dye structure and photophysical, photoelectrochemical properties and performance of DSSCs is described. For TPA-based dyes, by substituting the 3-hexylthiophene group with a carbon–carbon double bond as π-spacer, the bathochromic shift of absorption spectra and higher current density (J_sc) are achieved. When the methoxyl and n-hexoxyl are introduced into CM301 to construct dyes CM302 …