A thin pristine non-triarylamine hole-transporting material layer for efficient CH3NH3PbI3 perovskite solar cells

Abstract

A new non-traditional organic hole-transporting material (HTM), 4-(4-phenyl-4-α-naphthylbutadienyl)-N,N-bis(4-benzyl)-aniline (PNBA), has been employed in CH₃NH₃PbI₃ perovskite solar cells for the first time. The pore filling of PNBA into mesoporous TiO₂/CH₃NH₃PbI₃ scaffold is investigated in detail. As high as 11.4% of light-to-electricity conversion efficiency has been achieved, comparable to corresponding spiro-OMeTAD-based devices under the same conditions. It is revealed that the uniform and thin PNBA film is sufficient as a HTM for perovskite solar cells, and can facilitate hole transport to the metal cathode and also block electron transfer from the perovskite to the metal cathode.