Monolithic perovskite/perovskite/silicon triple-junction solar cells with cation double displacement enabled 2.0 eV perovskites

by Fuzong Xu, Erkan Aydin, Jiang Liu, Esma Ugur, George T. Harrison, Lujia Xu, Badri Vishal, Bumin K.  Yildirim, Mingcong Wang, Roshan Ali, Anand S. Subbiah, Aren Yazmaciyan, Shynggys Zhumagali, wenbo Yan, Yajun Gao, Zhaoning Song, Chongwen Li, Sheng Fu, Bin Chen, Atteq ur Rehman, Maxime Babics, Arsalan Razzaq, Michele De Bastiani, Thomas G. Allen, Udo Schwingenschlögl, Yanfa Yan, Frédéric Laquai, Edward H. Sargent, Stefaan De Wolf
Article Year: 2024 DOI:


Xu, F., Aydin, E., Liu, J., Ugur, E., Harrison, G., Xu, L., Vishal, B., Yildirim, B., Wang, M., Ali, R., Subbiah, A., Yazmaciyan, A., Zhumagali, S., Yan, W., Gao, Y., Song, Z., Li, C., Fu, S., Chen, B., Ur Rehman, A., Babics, M., Razzaq, A., De Bastiani, M., Allen, T., Schwingenschlögl, U., Yan, Y., Laquai, F., Sargent, E., De Wolf, S.


Perovskite/perovskite/silicon triple-junction solar cells hold promise for surpassing their two-junction counterparts in performance. Achieving this requires monolithic integration of a 2.0 eV bandgap perovskite subcell, characterized by a high bromide:iodide ratio (>7:3), and with low-temperature processability and high optoelectronic quality. However, light-induced phase segregation in such perovskites remains a challenge. To address this, we propose modifying the wide-band-gap perovskite with potassium thiocyanate (KSCN) and methylammonium iodide (MAI) co-additives, where SCN increases the perovskite grain size, reducing the grain boundary defect density; K+ immobilizes the halide, preventing the formation of halide vacancies; and MA+ eliminates the residual light-destabilizing SCN in the perovskite films via double displacement reactions. Our co-additive strategy enables enhanced photostability, whereas individual usage of MAI and KSCN would result in adverse effects. Triple-junction tandem solar cells, incorporating co-additive-modified 2.0 eV perovskites as top cell absorbers, reach a 3.04 V open-circuit voltage and a PCE of 26.4% over a 1 cm2 area.


triple-junction tandem solar cells light-induced phase segregation Wide bandgap perovskites additive  engineering high-voltage solar cells