Polar orientation of methylammonium cations in the vicinity of perovskite/hole-transporter interface studied by heterodynedetected vibrational sum-frequency spectroscopy

摘要

In the progress on perovskite solar cell design, lead halide perovskite thin-film sandwiched between the hole- and electron transport layers is one of mostly adopted structures.1 It was suggested that arrangement of the molecules near hole (electron) transfer layer plays a crucial role for determining the hole (electron) transport efficiency.2 However, arrangement of molecules at the interface of a perovskite thin-film has not been revealed at the molecular level.