Enhanced interfacial characteristics of perovskite solar cell with multi-functional organic hole-selective interlayer

In solution-processed organic and inorganic halide perovskite solar cells (PSCs), managing the interfacial characteristics between multi-layers has been a crucial factor in determining their performance and stability. Here, we newly design an indolocarbazole-based organic molecule that can enhance the interfacial properties between a solution-processed NiO x hole transport layer and perovskite in p-i-n planar PSC. Especially, to be beneficial to this architecture, its visible transparency and energy level are optimized, and its chemical structure is crosslinked for better solution processability as a hole-selective interlayer . More importantly, it can passivate the defects in the perovskite film, consequently enhancing the quality of the film and suppressing non-radiative recombination in the devices. With this interface modification, we confirm that the performance and stability of PSC devices are largely enhanced. • An indolocarbazole-based organic hole-selective interlayer is newly synthesized. • Its chemical structure is crosslinked for better solution processability. • This is added to the interface between NiO x and perovskite of p-i-n PV. • This modifies hydrophobicity of NiO x and passivates defects at the interface. • The efficiency increases from 16.1% to 18.2%, with over 500 h stability in air.