2D-π-A Type Organic Dyes Based on N,N-Dimethylaryl Amine and Rhodamine-3-acetic Acid for Dye-sensitized Solar Cells

Three organic dyes XS17-19 based on N,N-dimethylaryl amine and rhodamine-3-acetic acid moieties are designed and synthesized. These dyes were applied into nanocrystalline TiO2 dye-sensitized solar cells through standard operations, showing strong absorption bands at around 320-650 nm, and exhibiting broad IPCE responses. Cell based on XS17 gave a J(sc) of 3.7 mA/cm(2), an open circuit voltage of 550 mV, and a fill factor of 0.68, corresponding to an overall conversion efficiency of 1.4%. The low overall conversion efficiency is due to the modest IPCE and V-oc values, which mainly stem from the acceptor of rhodanine-3-acetic acid.