Novel diethylaniline D-A-π-A sensitizers for dye sensitized solar cells

Three diethylaniline D-A-pi-A sensitizers were designed and synthesized with diethylaniline as the electron donor, benzothiadiazole as the auxiliary acceptor, aryl ring as pi-bridge, and cyanoacrylic acid as the acceptor. Their photophysical, electrochemical and photoelectric conversion properties were measured and analyzed based on the difference of pi-bridge. The sensitizer with thiophene pi-bridge shows broader absorption region than the sensitizers with furan or benzene pi-bridges, which brings about its improved incident photo-to-current conversion efficiency and accordingly higher J(sc). In addition, DSSC based on the sensitizer with thiophene pi-bridge shows the largest charge recombination resistance and superior V-OC. Thus, among three diethylaniline sensitizers, dye with thiophene pi-bridge achieves optimal photoelectric conversion efficiency 5.42% (V-oc = 0.67 V, J(SC) = 11.51 mA cm(-2), ff = 0.70) under simulated AM 1.5 G irradiation (100 mW cm(-2) ). (C) 2019 Elsevier B.V. All rights reserved.