Enhanced (111) orientation resulted from hydrophobic protective layer for high efficiency and ambient stability of perovskite solar cells

Abstract

Perovskite solar cells (PSCs) have aroused great attention due to its low cost and high efficiency. However, the moisture instability is one of the main obstacle for its industrialization. In this work, we coated Methyl Succinamate (MS) hydrophobic protective layer on top of perovskite (PVK) layer with electron transport layer (ETL) prepared by chemical bath deposition (CBD). The ester and amide groups act as hydrophobic groups to prevent the erosion from water vapor. In addition, –NH₂ and C=O can interact with uncoordinated Pb²⁺ to stabilize the octahedral structure in PVK. Eventually, XRD results demonstrate that (111) orientation degree is greatly promoted from 0.09 to 0.25. In the end, the efficiency of the device prepared in the glove box increased by 0.76 %, from 21.99 % to 22.75 %. While, the maximum efficiency of the devices prepared in ambient was improved by 1.46 %, from 19.43 to 20.89 %, almost twice promotion of the devices prepared in N₂ atmosphere. This work manifest that enhanced (111) orientation is favorable for ambient preparation of PSCs.