A hydrophobic hole transporting oligothiophene for planar perovskite solar cells with improved stability

Abstract

An oligothiophene derivative named DR3TBDTT with high hydrophobicity was synthesized and functioned as the hole transporting material without an ion additive. 8.8% of power conversion efficiency was obtained for CH3NH3PbI3-xClx based planar solar cells with improved stability, compared to devices using Li-TFSI doped spiro-MeOTAD.