Triphenylamine 3,6-carbazole derivative as hole-transporting material for mixed cation perovskite solar cells

摘要

A new hole transporting material based on 3,6-disubstituted carbazole (3,6Cz-TPA) was synthesized through a one-step approach and was used as hole-transporting material in perovskite solar cells. The HTM exhibits molecular glass behavior and a high glass transition temperature of 146 A degrees C. A hole-mobility of 7.0 x 10(-6) cm(2) V-1 s(-1) has been measured which is slightly lower than the mobility of spiro-OMeTAD (2.5 x 10(-5) cm(2) V-1 s(-1)). The HOMO energy level, similar to the HOMO of spiro-OMeTAD, is suitable to allow the hole injection from the perovskite. Solar cells based on organic-inorganic hybrid cation perovskite light absorber have been built. The optimization of the concentration of the HTM shows an optimal concentration around 30 mM. Finally, the perovskite cells based on 3,6Cz-TPA as HTM lead to a power conversion efficiency around 16%, similar to the most commonly used spiro-OMeTAD (17%).