Effect of Pressure on Morphology and Crystallinity of the Perovskite Thin Film

doi:10.7517/j.issn.1674-0475.2017.04.035

Abstract

Abstract:

A novel and simple method to control the crystallization process during the formation of perovskite thin films is critical for optimizing the device fabrication process and constructing high efficiency perovskite solar cells. In this article, a method of adjusting the vacuum was used to effectively control the crystallization process. Furthermore, the role of pressure and its influence upon perovskite crystal growth, film formation and device performance were systematically investigated. The crystallinity and morphology of the perovskite thin film were characterized by scanning electron microscope (SEM), ultraviolet-visible absorption spectra (UV-Vis) and X-ray diffraction (XRD). Based on the structure of Glass/ITO/PEDOT:PSS/CH₃NH₃PbI₃/PCBM/Al, the performance of the device corresponding to the different pressure was studied. The results indicate that the decreased pressure can enhance the crystallinity of the perovskite film obviously, and improve the surface coverage by reducing the amount of holes. At the same time, the short circuit current, filling factor and photoelectric conversion efficiency of the device are all improved with the pressure decreasing. A 19% higher power conversion efficiency of 12.36% was achieved in comparison to the device fabricated by traditional method, which exhibited just 10.38% efficiency.

Key words: vacuum tuning, pressure, hole, perovskite solar cells

KONG Xiangbin, CHEN Yongzhen, LI Zhiyi, LIU Yanwei, WEI Xiaofang, LIU Jianjun, WANG Ruifang, WANG Ying. Effect of Pressure on Morphology and Crystallinity of the Perovskite Thin Film[J]. Imaging Science and Photochemistry, 2017, 35(5): 749-757.

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