Photoelectric conversion property of a photoresponsive D-π-A dye containing both NN and CHCH bonds

A new photoresponsive D-π-A dye, N-octadecyl-4-{2-[4-(2-(4-N,N-dimethylaminophenyl)azo)phenyl]ethenyl}pyridinium iodide (AEP) containing both CHCH and NN bonds, was synthesized, and N-octadecyl-4-[2-(4-N,N-dimethylaminophenyl)azo]pyridinium iodide (AP) and N-octadecyl-4-[2-(4-N,N-dimethylaminophenyl)ethenyl] pyridinium iodide (EP) were also synthesized for comparison. The photoelectric conversion (PEC) properties of the dye Langmuir–Blodgett (LB) monolayer films modified indium-tin oxide (ITO) electrode deposited under 20 mN m−1 of surface pressure were studied. The results show that AEP exhibits better PEC properties than AP and EP do. The photoelectric conversion efficiency is 0.31% for AEP in 0.5 mol L−1 KCl electrolyte solution under ambient condition, while those for AP and EP are 0.14 and 0.23% under the same conditions, respectively.