Organic D–π–A sensitizer with pyridinium as the acceptor group for dye-sensitized solar cells†
Two metal-free organic dyes with triphenylamide (TPA) as the donor group and pyridinium (m-carboxyl-N-methylpyridinium and N-methylcarboxylpyridinium) as the acceptor and anchoring group have been synthesized for dye-sensitized solar cells (DSSCs). A systematic investigation of the relationship between the structures and physical, electrochemical and photovoltaic properties has been conducted. The devices sensitized by TJ101 which employed m-carboxyl-N-methylpyridinium as the acceptor group has achieved a conversion efficiency of 5.4% (Jsc = 10.8 mA cm−2, Voc = 680 mV, FF = 74.2%) under AM 1.5 irradiation. In contrast, much lower efficiency of 4.0% was obtained when a reference dye TJ101R with m-carboxylpyridine as the acceptor group was employed as a sensitizer.