Synthesis of Self-organic Assembly Monolayers to Improve the Stability of Perovskite Films

Abstract

In recent years, photovoltaic devices based on perovskite materials have become one of the energy conversion field’s most in study topics. FAPbI3 stands out among a wide variety of perovskite structural materials with the advantages of a suitable band structure, long carrier diffusion distance, and so on. Unfortunately, the FAPbI3 perovskite films still lack some stability. It is well known that UV light and humidity strongly affect perovskite solar cell (PSC) performances, leading to the service life-time limitation of the device. Here, we propose strategies to improve the stability of PSCs by means of the interface engineering [1] between the electron transport layer and the perovskite active layer by inserting the self-organic assembled monolayers (SAMs). [2] The derivatives of Triethoxy(4-methoxyphenyl)silane (SAM1) and Triethoxy(3,4-dimethoxyphenyl)silane (SAM2) were synthesized using Grignard reaction [3] then inserted between the electron transport layer and perovskite active layer of PSC test devices in order to improve the hydrophobicity of the cell. Preliminary results showed that the perovskite active layers that have been modified with SAMs appear denser than those without modification. The overall conversion efficiency and stability of the SAMs-modified PSC devices will be further tested to prove more stable than those of unmodified devices.