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DOE OSTI · 1605075

Operando Microscopy Characterization of Perovskite Solar Cells

Xiao, Chuanxiao·Wang, Changlei·Jiang, Chun Sheng·Song, Zhaoning·Yan, Yanfa·Al-Jassim, Mowafak M
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Abstract

In this work, we developed operando Kelvin probe force microscopy (KPFM) to study the electrostatic potential distribution across perovskite cells under light and forward bias to gain a deeper understanding of device operation physics. As a case study, we selected perovskite cells with a SnO 2 -based electron-selective layer (ESL), which showed great potential for fabricating high-efficiency, hysteresis-free devices due to the deeper conduction band and higher electron mobility of SnO 2 . The as-made device showed a main junction at the perovskite/spiro interface. After light soaking and applying forward bias, the junction quality improved, possibly explained by filling trap states at the interfaces and by the perovskite absorber perhaps having a self-poling effect; the main junction is observed at the ESL/perovskite interface. The results are consistent with current-voltage measurements, device performance improves mainly with fill factor enhancement. The operando KPFM results should more closely reflect the real case during current density-voltage measurements or solar cell operation. The operando KPFM technique that we have developed can be a powerful tool to provide a deeper understanding of the device operation mechanism and to further optimize the device.

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14 SOLAR ENERGY36 MATERIALS SCIENCEenhancementfill factorinterfacejunction qualityoperando KPFMperovskite

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Xiao, Chuanxiao, Wang, Changlei, Jiang, Chun Sheng, Song, Zhaoning, Yan, Yanfa, Al-Jassim, Mowafak M. 2020-02-06. Operando Microscopy Characterization of Perovskite Solar Cells. https://doi.org/10.1109/pvsc40753.2019.8980640

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