Halide perovskite photovoltaics: Opportunities & challenges

by Prof. Alex Redinger (University of Luxembourg)

Thursday 10 Apr 2025, 16:15 → 17:30 Europe/Berlin

ENC-D114 (ENC)

Halide perovskite-based solar cells have demonstrated an unprecedented increase in power conversion efficiency over the past decade, reaching levels comparable to silicon-based photovoltaics in laboratory-scale devices. Their tunable optoelectronic properties, low fabrication costs, and ease of manufacturing make halide perovskites ideal candidates for both single- and multi-junction photovoltaic applications. However, their long-term stability remains a significant challenge for large-scale deployment.

In this talk, I will present how degradation of halide perovskites under white light can be monitored with nanometer-scale resolution using atomic force microscopy [1]. The degradation kinetics are examined in detail using X-ray photoelectron spectroscopy, and the atomistic origins of the degradation are revealed through density functional theory calculations. This multiscale analysis shows that degradation is initiated by a combined mechanism involving both light exposure and the presence of material defects.

I will also discuss effective mitigation strategies, including the application of passivation layers [2] and optical filters. A comparison will be made between degradation behavior in ultra-high vacuum and in dry nitrogen environments. Finally, the light stability of Sn-based halide perovskite absorbers will be compared to their Pb-based counterparts, to better assess the feasibility of lead-free perovskites [3].

[1] Hieulle, J., Krishna, A., Boziki, A., Audinot, J. N., Farooq, M. U., Machado, J. F., Mladenović, M., Phirke, H., Singh, A., Wirtz, T., Tkatchenko, A., Graetzel, M., Hagfeldt, A., & Redinger, A. (2023). Energy and Environmental Science, 17(1), 284–295.

[2] Krishna, A., Škorjanc, V., Dankl, M., Hieulle, J., Phirke, H., Singh, A., Alharbi, E. A., Zhang, H., Eickemeyer, F., Zakeeruddin, S. M., Reddy, G. N. M., Redinger, A., Rothlisberger, U., Grätzel, M., & Hagfeldt, A. (2023). ACS Energy Letters, 8(8), 3604–3613.

[3] Machado, J. F., Hieulle, J., Vanderhaegen, A., & Redinger, A. (2024). J. Mater. Chem. A, 2025, 13, 517