Benefits of the Hydrophobic Surface for CH<sub>3</sub>NH<sub>3</sub>PbI<sub>3</sub> Crystalline Growth towards Highly Efficient Inverted Perovskite Solar Cells

In inverted perovskite solar cells (PSCs), high-quality perovskite film grown on hole-transporting material (HTM) with pinhole-free coverage and a large grain size is crucial for high efficiency. Here, we report on the growth of pinhole-free and large grain CH<sub>3</sub>NH<sub>3&l...

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Bibliographic Details
Main Authors: Yang Li, Zheng Xu, Suling Zhao, Dandan Song, Bo Qiao, Youqin Zhu, Juan Meng
Format: Article
Language:English
Published: MDPI AG 2019-05-01
Series:Molecules
Subjects:
Online Access:https://www.mdpi.com/1420-3049/24/10/2027
Description
Summary:In inverted perovskite solar cells (PSCs), high-quality perovskite film grown on hole-transporting material (HTM) with pinhole-free coverage and a large grain size is crucial for high efficiency. Here, we report on the growth of pinhole-free and large grain CH<sub>3</sub>NH<sub>3</sub>PbI<sub>3</sub> crystals favored by a hydrophobic small molecular HTM, namely, 4,4&#8242;-Bis(4-(di-p-toyl)aminostyryl)biphenyl (TPASBP). The hydrophobic surface induced by TPASBP suppressed the density of the perovskite nuclei and heterogeneous nucleation, thus promoting the perovskite to grow into a dense and homogeneous film with a large grain size. The CH<sub>3</sub>NH<sub>3</sub>PbI<sub>3</sub> deposited on the TPASBP exhibited better crystallization and a lower trap density than that on the hydrophilic surface of indium tin oxide (ITO), resulting in a significant reduction in carrier recombination. Combined with the efficient hole extraction ability of TPASBP, a high efficiency of 18.72% in the inverted PSCs fabricated on TPASBP was achieved.
ISSN:1420-3049